(00:00:00) We're going to spend the rest of the hour as a matter of fact talking about the weather. Jim Campbell is with us meteorologist in charge of the Twin Cities Office of the weather bureau. Jim. Welcome. Nice to have you (00:00:08) back. Thanks Bob. It's always a pleasure to be here (00:00:11) seems like the worst of the wind is behind us already (00:00:13) know but at that moment it seems that way after are really cold December and things have warmed up now and looks like next few days. It's going to stay on the warm side. We're probably going to get up above freezing tomorrow and Southern Minnesota. So it's a nice change from the real cold weather in December. (00:00:28) Do you think we've had it for the cold weather (00:00:30) now? I think it'd be a little premature to say that we've had it for the cold weather. Generally January is our coldest month and this particular period from the 10th of January to the 20th of January is usually the coldest of the year, but the pattern we're in right now would be indicate that we're probably going to stay on the warm side. At least for the next several days if we (00:00:51) can if we can get through next week without getting really bitter cold and then really there's only just the one week after that that theoretically Really be (00:01:00) awful. Theoretically that's right. But you never know you get like happened in December. We got a real cold outbreak coming out of the Arctic and that are was coming almost directly from the North Pole. And as a result, we had those cold temperatures only Rising Lee saw it was back in 1983. It was actually a lot colder in December of 83 than it was in this December. I think this December was the seventh coldest ever and the one back in 1983 where something like minus 2.9 below zero was our average temperature for the month. So it was even much colder than (00:01:33) what happened. If I remember when we had that cold snap in December, it just went for days and days and days and then finally something happened to to break that pattern up what happened in the upper (00:01:43) atmosphere what happened we had we had established a pattern of strong Ridge over the Gulf of Alaska and during that period of time effect Alaska was a lot warmer than we were and that's generally the case when you get a ridge of high pressure over Alaska in the winter time. You get the jet stream coming down across the Arctic and then into the Upper Midwest and so that brings in that very cold and dry air and that Ridge broke down a little bit before Christmas and we got into a more normal pattern of more what we call zonal Flow which is a west to east flow across the country and that brought in the warmer maritime air that came across the mountains and then into Minnesota and we've pretty much been in that pattern ever since then with occasional we get a little bit of fronts that come down through this kind of a battle going on between that Arctic air in the maritime air. And when the Arctic air wins, we get a little bit colder temperatures and when the maritime air wins, it gets a little warmer like it will be tomorrow and has been in the last week. (00:02:39) Jim Campbell is with us. If you have a question about our winter weather today, you can give us a call Mild winter weather though. It may be in the Twin Cities area. The number is two two seven six thousand 2 2 7 6 thousand in the Twin Cities outside Minneapolis st. Paul anywhere within the state of Minnesota one. 865 2 9 7 0 Zero one eight hundred 6529700 and those of you in the surrounding states or in Ontario can call us directly at area code 612 2276 thousand as Force. No, we have not. It seems to me had very much snow so far this year (00:03:19) now, but surprisingly are we've had a little over 18 inches, which is pretty close to normal are normal snowfall in the Twin Cities is just about 50 inches in a year and through December and remember in December and in January right around 18 inches is about what's normal. I think what's the difference has been as we've gotten the amounts of common inch and a time or half an inch at a time and and just have accumulated plus the snow that we got in November a lot of that melted. So it doesn't seem like there's been much and really it's been a pretty quiet winter. I think the last time we had a winter storm watch for Minnesota was back in in the end of November so compared to other winners. It's been pretty quiet. Hmm. What are you expecting (00:03:59) for? For the balance of the winter in terms of snow (00:04:02) the the 30 day outlook for January is calling for continued dry with precipitation below normal and and temperatures remaining near normal in the 3-month forecast, which concludes January through March is also calling for below normal precipitation and below normal temperatures through that period so if it's right we'll get into back into some of those colder temperatures maybe a little later on (00:04:27) but below below normal precipitation. That's a bit worrisome because we ended 89 with a moisture deficit in we (00:04:35) write we were three inches Below in the Twin Cities and over the state. It ranged anywhere from about 3 to 6 inches below normal for the year and we've been below normal for about the last four or five months course, the winter months the snow. There's not a lot of water equivalent in that snow. So that's not real critical the critical times going to come in the spring one of the things that's happened. This year is because of the cold weather and November and December. And not much snow cover during that period of time the frost level has gotten quite deep and when that happens, even if you do to get heavy snows the snow tens the runoff then in the spring, it runs off instead of soaks into the soil and that's going to be a detriment to agriculture. That's assuming we get to more normal snow covers the more snow, you know in the next couple of (00:05:20) months. Mmm-hmm. Jim Campbell is with us at about a quarter after the hour and we've got some folks with questions for him about whether weather phenomena of various types. So we'll put you on first hello there. (00:05:31) Mr. Campbell and I particularly in December when it got so cold. I wished I that I knew how to kind of estimate the warmest part of the day if we knew if I could figure out some way between noon and sunset. For instance when the warmest part generally comes it would have been a great help. (00:05:50) Usually the warmest temperatures of the day come in the mid-to-late afternoon. That's when the sun has its maximum effect of heating of course the heating effect of And because it's so low in the sky this time of year is not that strong but generally somewhere between about 2 p.m. And maybe 3:30 or 4 is when we get our maximum temperatures providing. There's not a frontal system moving in or something like that where there's a change of air mass occasionally we can get falling temperatures during the day and it doesn't matter how strong the sun is because the air is so cold but as a general rule in mid-afternoon is about the maximum temperature (00:06:27) at the other end of the scale. I've noticed many times if I get up very early in the morning, it'll be warmer at 5 or 4 in the morning than it is at seven or six and why is (00:06:39) that? Well, the reason for that is that once the sunsets what happens is that the heat that the Earth is holding radiates out into the sky and especially on nights when you have clear sky in a snow cover snow is a very excellent radiator of this long wave radiation and until that sun really gets up above the horizon. And it doesn't really begin to warm up. So the temperatures will actually continue to drop until sometimes, you know, seven even we sometimes we get our minimum temperature in December and early part of January as late as 8:00 o'clock in the morning because the sun doesn't even come up until almost 8 o'clock or a little bit before so it continues to drop until that sun gets above the Horizon. (00:07:20) All right our next question for Jim Campbell from you. Hello there. (00:07:23) Good morning. I had a couple of questions. Type shows as I don't know whether it's a physical or mathematical concept which precludes anything more than dicey prediction beyond the first few days and the second question was I don't quite understand the physics of why the latest hour of Sunrise or the period of latest hour of Sunrise precedes the solstice by perhaps a week or two. (00:07:55) As far as the first question on the chaos now as far as that applies to forecasting we haven't in meteorology. We really haven't got into that as far as trying to determine whether that has any bearing on the forecast. The chaos is more of a I think a longer term type of thing in in the structure of physical things that over a long period of time the action of the atoms and the molecules begin to perhaps cause some sort of breakup or some sort of problem. And that's a very mathematical content in physical kind of thing that I personally don't know a lot about but it hasn't really applied too much to meteorology as far as the why the the sun actually comes up a little bit later than the solstice. I'm not really sure that it's a it's an astronomical effect that occurs. I think it's the time of the day the sunset and the sunset and the sunrise to Sunrise tends to be a little bit later, but the sun sets begin to Become later on in the afternoon. Although the sunrise is a little bit later before it swings back and it's probably just related to the position of the earth and where we are but I don't know the exact exact cause of that, (00:09:04) you know, it's the day is getting longer already though, don't (00:09:06) you? Yeah. Yeah, that's that's a nice part of the day and they begin to get longer fairly rapidly to by the end of the (00:09:13) month. Mmm-hmm. Pretty soon. We'll be back Daylight Saving. That's right. You're on the air now with Jim Campbell. What's your (00:09:18) question? Yes after the cold weather we had in December. I started to wonder if they were really true about the greenhouse effect caused by our environmental air pollution and such but do you think that the lack of snow and the upcoming lack of snow prediction is really the same thing as we had in 1988 with the drought in the summer, except. We're just having it in the winter instead and if it's a continuation of our despoiling of the environment with all our exhaust and everything that's causing the greenhouse effect in that way and I'll hang up and listen to your answer. (00:09:53) Okay. Well as far as the greenhouse effect, it's interesting because yes, the question came up when we got real cold in December about the Greenhouse Effect and and you know, what happened to the greenhouse effect. The main problem is is when you have air that's coming directly from the North Pole. It doesn't matter whether there's a greenhouse effect or not. It's still going to be very cold. In fact, there was even a little joking around our office that just think how much colder for benefit hadn't been for the greenhouse effect. But the greenhouse effect. It's it's very difficult to especially in the short term weather events to determine whether there is effect and the greenhouse effect. It does exist. The scientists have shown that the amount of carbon dioxide has increased in the atmosphere over the years and we do know that carbon dioxide traps the long-wave radiation that is reflected back into the atmosphere and acts as a blanket. So that is a fact what what is going to happen and how that's going to affect our weather. There's a lot of controversy. See in that area of whether that will be you know, the summer of 88 is going to be typical in another 40 or 50 years. There's there's a group of scientists that believe that there's another group that aren't really so sure how it's going to affect our weather pattern. My my personal opinion is that we've got to do something about it in relation to what's happening in the destruction of the rainforests the fact that we are increasing the levels of carbon dioxide and other emissions in the atmosphere that somewhere there's probably going to be in effect what that effect is going to be it's hard to say we do seem to be in a drought pattern that's been almost since 1987, but we had periods like this back in the 1930s before the Greenhouse Effect and we knew as much about it and it increased its strength since then so it's very it's very difficult to say what impact that's going to have. Now the continuation of the drought there. There's even another theory that we're looking at a Period of a sunspot cycle here the maximum being in March and there has been some evidence in the past that the 11-year Sunspot Cycle that there has been dryness in the Midwest and that certainly would match up very nicely with that. So it's possible that could be a contributor as well. Hmm (00:12:09) But we are seeing a continuation of the drought this winter you would you would (00:12:12) yeah, we've been below normal for the last four or five months and as far as the precipitation but again when you when you talk about an average snowfall is about 8 or 9 inches each month during the winter months and if you reduce that to that's probably a little bit less than an inch of water over. Also, you know, I real are real important part of our precipitation comes in the spring and summer months. I'll (00:12:37) take another question here in a minute, but back to the to the cold in December just for a second. I had always heard that that it can't get really cold. If there isn't a good snow cover. We didn't have a lot of snow cover in December and it's still just got bitterly cold. (00:12:53) Well, what happens is and the reason it gets cold when there's a when there's a good snow cover. Is it because as the sun heats the Earth surface, the shortwave radiation comes in and Strikes the land and then that is converted into warmth and then long ray radiation is radiated back up into the atmosphere and snow happens to be a very excellent radiator of this long wave radiation. And so what happens is when you have a snow cover in a clear night with no wind a lot of that radiation goes out into space very quickly. And as a result, you can get the cold temperatures. The reason that that we got the cold temperatures in December, even though there was not a lot of snow cover really had to do with the fact again, you were looking at very very cold air that had come out of the source region was the North Pole in Siberia comes right across the Poland right straight into the into Minnesota. And so whether there's snow cover or not, it's going to be cold had there been had there been more snow cover. And we had nights with very light winds. We probably would have seen colder overnight lows because of that. Mmm. (00:13:59) All right back to the phones and more questions. Jim Campbell chief meteorologist of the Twin Cities Office of the weather service is with us and thank you for calling you're on the air. (00:14:07) Yeah. I've got a question on it seems every morning right before the sunrise it always gets colder, even though it has stabilized like one hour before Sunrise. It has a tendency to drop one or two degrees. Is there a reason for (00:14:23) that now, I think it's just as we were talking earlier the fact that because the sun isn't up yet. And actually the sun really has to get a somewhat above the Horizon especially this time of year to start warming that you will get that drop in temperature throughout the night and it is true. Sometimes there is a little stability what can happen is is maybe right before Sunrise the winds will drop off to calm and of course any time there's wind that stirs up the atmosphere and that tends to hold the temperatures up a little bit. So if the winds do happen to Pop off right before Sunrise, then you can get another degree or two drop in temperature and that probably what accounts for it. (00:14:59) We have a couple of lines open again in the Twin Cities area. The number is two two seven six thousand 2276 thousand if you got a weather question today for Jim Campbell and the toll-free number for those of you outside Minneapolis. St. Paul is one 865 29700 now, it's your turn. Where you calling from today. (00:15:19) I'm calling from st. Cloud. All right. What's your question for Jim? I have two questions one is I'm interested in a fairly comprehensive historical listing of various weather information. I'm thinking of temperature pressure humidity wind speed things like that on a daily basis. Is there a sort of a large volume that would provide that information and the second question is I'm interested in if there's a periodical available providing that sort of information for more current information. (00:15:49) Yeah, if you're particularly looking for st. Cloud. You should be able to go out to the st. Cloud Airport. There there the weather office is right near the airport and they should have something called the local climatological data, which has a breakdown of a lot of that information for longer term information. Probably the best thing to do is write to the National climatic Center in Asheville, North Carolina. And I think you can if you check with the weather office at st. Cloud, they probably can get you an address or a phone number and they can provide all kinds of long-term historical data. (00:16:24) Okay. Next question for Jim Campbell from you. Hello (00:16:27) there good morning morning wind chill is always referred to as the effect that of cold on the human flesh. Hmm. What kind of effect is windchill have an inanimate objects like cars. (00:16:40) Nothing. No matter if the temperature is 10 below outside in the wind chill is 50 below your car is going to be 10 below zero, once it cools all the way down the only That it makes is is if you have your car outside its the windchill is going to help it cool faster, but it will not get below whatever the air temperature is (00:17:01) that's comforting to know when you're at a freeze is good to 30 below. (00:17:04) Yes. It can yeah, if the wind chills 50 or antifreezes will still be good. (00:17:09) Okay, next question. Hi there. Thank you for calling and you're on now with Jim Campbell. (00:17:13) I'm calling from Duluth where the ice is blown in on the lake. Mmm. It has it has long been of interest to me that in the area around Lake Superior. the climate for example, you can see this marked on maps from seed companies is approximately 1 climate zone south of the immediate surrounding area. Would you care to comment on that, (00:17:41) please? Yeah that has to do with the effect of the of the large lakes up there any time you have a large body of water what happens in the wintertime, especially before that body of water freezes. The water is a lot warmer than the areas around the land. So when you have a wind flow off the Lakes the temperatures can be somewhat warmer than they may be in fact quite a bit warmer than they are 15 or 20 miles Inland because of the effect of the lake same is true in the summertime. You know, the I think Duluth has the reputation of the air-conditioned City and during the summertime. The lakes are generally cooler than the surrounding land areas. And so again with a with a breeze off the lakes that brings in the cooler air off the lakes that that has been cooled by the water and I know that places like Grand Marais up in the up in the Northeast part that Temperatures can be considerably warmer because of the lake effect during the wintertime than it is say 15 miles Inland where it may be, you know tens of degrees below zero and it can be all above zero or near zero right along the lake there and that's all because of the effect of the (00:18:47) Lakes. It's kind of a mini ocean isn't (00:18:49) it? Right? And that also can affect the amount of snowfall to we get because of the terrain effects up in the up in the arrowhead of Minnesota and the flow off the Lakes there can be enhanced snow fall along those Lakes as well because of that and that's again because the air becomes more moisture Laden at the lower levels and goes Inland and then it rises a little bit and cools very quickly and then precipitates out as snow and that can cause the increase amount of snow along the (00:19:14) lakes. Does that help protect them in the summertime from tornadoes? You don't hear a whole lot about tornadoes up on the North Shore. (00:19:22) I wouldn't say that in a situation where you have a large very strong thunderstorm complex. That's probably not going to make Much difference you do get some kind of Lake Breeze coming off the lakes that they could have some local effects on perhaps some of the thunderstorms but I wouldn't want to go so far as to say that it could prevent or severe weather because we've had tornadoes up in Duluth and under the right circumstances. You could get a strong enough tornado in the Lake of the effect of the lake just wouldn't be strong enough to overcome it. (00:19:53) Well, that's our conversation for the summer. Anyway, just a little yeah. Let's move on to your question now. Hi, you're on with Jim Campbell (00:20:01) morning. I'm from Deephaven and I have a weather related question, which you may or may not be able to answer Jim. I'm a pilot and I watch quite regularly our public TV station which shows the weather broadcast and forecasts and I have a problem in the my screen does not pick up the digital material rolls off on the upper right hand corner of the screen and I've been hoping for years. They would shrink that image a little bit so we could see the whole screen. Is that a come under your purview or not? There's Program a source now that really (00:20:35) they get some of their information from us, but actually the the maps that are provided are done by kovorix corporation, which is a weather outfit. In fact, they actually work in the same building that we do out at the airport and they provide those maps to two channel 17 and that's done through the Department of Transportation the universe at the ministry of Minnesota. And you know, you might want to contact them. There might be something that they could do electronically to, you know, look into that but we don't have any control over that as far as what goes on 17 (00:21:10) do broadcast your own weather radar on there. (00:21:14) They yeah, they some of the rare. Yeah, what happens is though, it's our radar but it's taken by the course Corporation. And again, they see they reformat it for their user and then it's given over to channel 17. It's not a direct link. What do the (00:21:27) Colours mean? They're usually different (00:21:29) colors. Yeah the colors the The cooler colors the greens generally indicate light precipitation. The yellows are the begin to get a heavier precipitation. And then the reds are the strongest returned from the radar. That's usually an indication not always at their severe weather but there's a very strong return from the radar it can mean hail or it can mean very heavy rains. And those are the kind of things that are capable of producing severe weather under the right circumstances. (00:21:56) All right, another question from a listener here and it's your turn to talk to Jim Campbell High. (00:22:00) Hello. I'm calling from and my question has to do with the Antarctica. I understand that there's been a number of studies or some studies that have been carried on in regard to how Antarctica influences the world's climate and I'm wondering if you could comment on those or if you have any other information I'll just hang up and listen. (00:22:22) Thanks. Okay. I don't have a lot of information. I'm not sure that an article would have a great effect on the weather in the northern hemisphere, generally. Northern and southern hemisphere operate under two different regimes. The Northern Hemisphere flow is a result of the land and ocean masses as well as the southern hemisphere, but there's a dividing line called the intertropical Convergence Zone near the equator which has a tendency to move back and forth during as the season's pass a few degrees either side of the Equator and it's the spawning ground for hurricanes during the summer time, but generally the the way that our weather system works that there is not a lot of crossing of the atmospheric or the winds across that intertropical Convergence Zone. So what happens in the I Antarctic probably has more of an effect on the southern hemisphere than it does on the Northern Hemisphere because we are tended to be influenced by the land masses in the ocean masses just in the northern hemisphere. (00:23:23) I have heard that our winds generally tend to blow west to east is that right? That's (00:23:28) that's correct that has to do with the rotation of the earth is really what causes that and other physical forces. Yeah, are there (00:23:35) any parts of the world where the wind would tend to blow from east to west (00:23:39) near the equator they blow from east to west and there is some blowing from the east to west in the southern hemisphere as well. Hmm. (00:23:47) All right 28 minutes before twelve o'clock. Jim Campbell is with us listening for you now. Hello. Where are you calling from (00:23:52) calling from Rochester Minnesota. Yes, sir. Degree days are calculated and where such historical data could be obtained locally or for region. So a person could calculate roughly how well is houses insulated by actually looking at monthly averages or even weekly averages of heating degree days. I'll hang up and listen. (00:24:12) Thanks. Okay, heating degree to Heating and Cooling Degree Days use a base of 65 degrees. And what we do is we take the high temperature for the day and the low temperature for the day and average those Two out and let's just say for an example. Let's say we take the high and low temperature and average those two out in the average for the average for the day would be 35 degrees. All right, so the so the difference between 35 degrees and 65 degrees is 30. So when it's below 65, that would be 30 heating degree days. And then those are accumulated each day. If you're living in Rochester, you should be able to get that information from the National Weather Service office there in Rochester and sometimes I know for example on our NOAA Weather Radio that we operate out of the Twin Cities and they have one in Rochester as well. I know on ours in the Twin Cities we put heating and cooling Degree Days daily on our climatological information. That's put out on that weather radio, and I don't know if you have a weather radio or not, but you can get a lot of that information usually awful Weather Radio and they operate when they're in Rochester as well. (00:25:16) Is there some practical use that a individual can make out of that (00:25:19) data? Well, I it's good it kind of gives you an idea. You want to keep track of how your heating costs are going to be going the I don't have a specific formula on you know, how many heating Degree Days versus the cost. But of course the higher the number of heating Degree Days, the the more heat is going to cost now the company's gas companies and utility companies use that kind of information a lot to be able to not only forecast their demands by looking ahead what the temperatures are going to be but it helps for people who have say oil heat after they know when to go fill people's tanks because of the amount of heating Degree Days and the amount of gas that they may be ordering through their pipelines or something like that can be determined by that. So there is a lot of usefulness for that information. (00:26:04) Mhm. Next question for Jim Campbell from you. Hello. You're on the (00:26:08) air. Yes. I'm wondering about Sunspot. I understand that the sun is giving up extra amount of sun spots right now. I'm trying to study them and I also understand that the sunspots have there's some correlation. To in a sunspot and droughts. Can you give me any reason for that? I'll hang up and listen. (00:26:29) Hey, yeah, there is we are approaching the maximum 11-year Sunspot Cycle which is to take place in March and I know it's been this has been a fairly active time. There's been a lot of the northern lights or the Aurora Borealis this winter and during the fall and I know the people who study those of said that the activity has been quite High there has been some correlation. We talked about a little earlier on a program between the 11-year sunspot cycle at attaining me maximum of the cycle and some patterns for lesser amounts of rainfall in the Upper Midwest. However, the correlation is not it's not real strong in some instances. And in addition what causes the to change in change in the weather that would cause a drought we don't really know the answer to that, you know, the particles a lot of those ionized particles come off the surface of the Sun and Perhaps have some effect on the on the atmosphere but you know, we've been drying the Midwest but you can go over to the east coast and the East Coast has had above normal precipitation of the last couple of years. They've had a lot of storms have had a lot of winter storms this year. So whether that's directly related to the sunspots, it's hard to say but the long-term shows that there is a little bit of correlation between that and and the cycle (00:27:46) very interesting another question for Jim Campbell. You're on the air with him. Go ahead, (00:27:49) please. Hi. I'm teaching a unit on electricity to elementary students and I have a three-part question on Lightning. First of all, what causes the lightning to build up in the clouds second of all, if you have any statistics of numbers of people that have gotten hurt from lightning strikes or places in the country that that's more likely to happen and third of all then safety precautions that I could pass on to my students. (00:28:12) Thank you. Okay. First of all, lightning is caused what happens is that there's a large buildup in the positive charges in the base of a cloud and Induces a negative build up charges on the surface of the Earth. And what happens is when that electrical potential becomes great enough that it overcomes the insulating properties of air and air is a pretty good insulator when that electrical potential gets very great than that that insulating property breaks down and you form a bolt of lightning now lightning also can occur within the cloud itself or from Cloud to Cloud but the cloud to ground strokes of course are the ones that are the most dangerous. We probably kill about it somewhere around 80 to 90 people each year in the United States and we average about two to four people in the state of Minnesota each year that are killed by lightning and then injuries probably in several hundred throughout the nation each year and in Minnesota, we have injuries as high as 25 or 30 people are injured each year by lightning. So the main safety precautions as far as Lightning goes as First of all is to be indoors most people that are killed or injured by lightning are done. So outside things like standing out in an open field or under a Lone Tree are the most dangerous because lightning tends to strike the highest object around so you want to avoid those kinds of situations being inside a building gives you a some insulation and some protection. However, if you're in a home or something like that, it's not a good idea to be taking a shower working around appliances because of lightning does hit a home what happens is it can get into the electrical hit system or heating system or into the water pipes and the course water and and electrical pipes and appliances. Anything metal are very good conductors So to avoid things like that talking on the telephone and something we also don't recommend unless it's an emergency because lightning can hit an outside phone line and come into the house and and statistics show that about one to two people in the United States are killed each year talking on. Telephone so staying away from water. That's another dangerous getting out of swimming because of water if lightning hits water, of course again, being a very good conductor being out on a golf course or out being on tractors or any kind of bicycles anything like that is also dangerous during lightning storm. So we want to avoid those kind of situations as well. (00:30:45) It's very unusual to have lightning in the winter. (00:30:48) Why well, one of the reasons is that lightning it does occur. In fact more more than I think a lot of people think we've had it a number of times here in the Twin Cities when we have a very strong system. And what happens is you get the build-up of these systems where the heights of the clouds maybe get to twenty thirty thousand feet. And of course snow is a very carries electrical charges very well. And so when you have a strong system, you can get what we call thundersnow but generally speaking the cloud tops are quite low you don't get the Strong separation between the positive and the negative charges and as a result, you don't get that breakdown of the of the insulating property. So in a general rule, you don't get that much lightning during the winter months. (00:31:34) Hmm and the clouds themselves are not as tall in the (00:31:36) winter. Now when you you know, when you get lighting out of a thunderstorm, you're looking at storms that are anywheres from 42 high as 65 to even 70,000 feet in the very large storms in the wintertime Cloud tops may only be running 15 to his much as maybe 25,000 feet at most that's why a lot of times we don't see snow too well on radar because if you leave you're ever looking at radar you may see it's snowing around the Twin Cities and it may be snowing in a place like Redwood Falls, but we don't see it on radar because the radar beam is actually shooting over the top of the the clouds so they don't get that high during the winter time. Hmm. (00:32:13) All right back to the phones more questions for Jim Campbell today, and you're next to Lowell. Yeah, go ahead (00:32:19) please. Hello. I wonder if you could say something about what causes fog at various times of the year. That's always been hard for me to understand. (00:32:28) Okay, what happens fog is caused when the atmosphere depending on what the temperature is the atmosphere can hold only so much water and once the atmosphere becomes saturated and it begins to cool. What happens is that water vapor in the atmosphere condenses. And when that water vapor condenses it forms a cloud which you see, you know, during the summertime at levels of five ten thousand feet or whatever and at some times of the year when that happens very close to the ground. Essentially. What's happening is you're forming Cloud right on the ground and a lot of times it can eat we can get fog in the winter. What happens is you have a very cold ground and you get some very warm moist air moving over snow covered ground. And what happens is that there's too much moisture for the year to hold so some of it That's as out and it at forms fog and it can be very thick at times even so the fog is basically a cloud that's on the (00:33:25) ground with all due respect to my fourth or maybe fifth grade teacher who surely taught me this a thousand years ago. Why does frost form on the windshields of cars (00:33:36) it again the it forms on the windshield and will form on the metal Parts as well because first of all, they tend to cool the metal Parts cool fairly quickly. And what happens is that any moisture in the atmosphere because the metal and sometimes the glass cools a little faster than the ground does that moisture will condense out again you reach that point. It's the same Principle as fog except in the winter time when the temperature is below freezing instead of forming a cloud that forms the frost you get the little ice crystals and so they tend to form on cars and on car windows because they cool a little bit quicker sometimes, you know, they'll be frost on like I think what you're saying is will be frost on the car, but maybe not on the ground. And it's because at those surfaces will cool faster. And remember the ground sometimes holds heat from during the day. The sun's been shining on it and tends to be a little warmer where objects above the ground will tend to cool faster. (00:34:31) We have about 15 minutes left here with Jim Campbell chief of the Weather Service Office of the Twin Cities and a couple of lines again open. The toll-free number is 1-800-695-1418 Hot Side Minneapolis, st. Paul and 2276 thousand in the Twin Cities. Thanks for waiting. You're on with Jim now. What's your question? (00:34:54) Verb analysis up in Bemidji and we were taught that there was a hundred and fifty years cycle approximately called the all the fennel and the antis animal and then inside that cycle over several up and dogs unlike the 22 year basis, which is somewhat by the sunspot cycle and I was curious that where we might be in the open and I'm alone and I will cycle right now and how many cycles in between the you normally (00:35:17) get? Yeah. I don't really know too much about either one of those Cycles there. There are people who study cycles and one of the problems in meteorology and trying to study Cycles is that if the amount of data we have is very very small meteorology is fairly young science. We don't have good records much more than about a hundred years or so, you know with the only records we have is what the climatologists have been able to find by looking at soil samples and samples taken off the ocean floor that go back, you know hundreds of thousands and millions of years, but we don't Many kinds of record weather records from those are and so it's very very hard to determine Cycles from the from the small amount of data that we have same thing with hurricane Cycles. There seemed to be some Cycles in the early part of the 1900s for a while. They were along the east coast and then they switch to the Gulf Coast and then back to the east coast and last 10 or 15 years. We've kind of been alternating between those two. So it's very hard to say. I'm not being familiar with those two cycles. I couldn't tell you exactly where we are in those but I think there's probably some validity to Cycles it just that we don't know enough about them and there may be, you know more than one or two cycles and how they interact together. That's something we just don't know until we get to we get more data, I (00:36:39) think okay another whether question for Jim Campbell and we'll go to you this time at all. (00:36:45) Thank you. (00:36:48) Where are you calling from? (00:36:49) Well, I'm calling from Michigan over near Houghton and (00:36:51) Hancock. Terrific. What's your (00:36:53) question? Always been interested in whether or not you folks can explain the Aurora Borealis. Give it a give it a (00:37:03) whirl. Which well, I'll give it a whirl. I'm not really that's really a physicist domain more than a more than a meteorologist because it's not a it's not a meteorological phenomenon, but the way I understand it is what you get the super charged ions coming off the F the sun when you get these very strong storms that are upped on the sun's surface and what happens is that as that as those ions strike the outer portion of the atmosphere the atoms out there what the electrons that surround those atoms get because of the energy involved get pushed to a higher level and when they fall back light is created and in that process of doing that with these large solar streams the electrons that happens, of course quite a bit and it's a constant stream of Ions that are they're bombarding the Earth surface. So these electrons are getting pushed up to these higher level rings. And then when they fall back they produce the light and and I think you get you know, the various colors can sometime depend on the atmospheric conditions as well as I guess how much those electrons are pushed around and it's probably not a great answer but that's about the best I can do. Well, I do better understanding (00:38:17) frost on windshields telling the truth. Let's move back to your question. Hello there. What's your question? (00:38:23) Yeah. I came up with a couple questions in regards to your discussion on lightning and I was wondering if the gentleman would like to make a comment on the phenomenon of ball lightning and what you know what it's probabilities are how rare it is. And if there are any weather phenomena that contribute noticeably to it. Thank you all hang up and listen (00:38:48) Okay for the listeners that ball lightning is a it's a very strange phenomenon. It's been documented throughout history. Three and it's a very infrequent occurrence. There are some scientists that aren't really sure it exists but there have been some very good eye witness accounts. And what what ball lightning is essentially it looks like a ball of what-a-light and there have been accounts that where they have, you know, floated through open windows and then and then disappeared people have seen them, you know Rolling Along fences or something like that and really what causes them. No one no one really knows for sure. What causes ball lightning is based on some of the eyewitness accounts that I've read and some of the some there have been people who've tried to study I think that it does exist, but it's a very rare phenomenon and what what kind of weather event it's related to or whether it's a may not even be related to weather itself. It may be a physical property of the lightning itself or in the atmosphere that causes it but there's so few instants of it and and very difficult to study that we just don't know that much about it. So what causes it? I don't know ever seen it yourself now I've never seen (00:39:55) Our next call comes from you. You're you're listening to us where Chester yes, please (00:40:00) I'd like to know what the current thinking is on actually, how does a tornado form in a severe thunderstorm what actually I've heard that it can be induced by lightning or some electrical phenomena. I'll hang up and (00:40:11) listen I the latest thinking is is probably the electrical activity does not have a lot to do with forming a tornado. We don't really know all the answers what what we think happens is when you get a very large thunderstorm, that's a we would call a steady-state thunderstorm meaning that it lasts for a long period of time you you establish very strong updrafts and downdrafts within the thunderstorm. The updraft is rapidly Rising air that virtually is feeding the storm and that is helped by sometimes a strong jet stream above the storm that acts as like a chimney effect of strong winds blowing across the top. It tends to draw the air up Into the Storm at the same time as rain and hail begin to fall out of the storm that sets up a downdraft. Where you can get very strong winds coming out of the storm itself. Well, we think happens is that as the air is drawn into the thunderstorm. It begins to very slowly rotate and we have pictures where you can see entire thunderstorms actually rotating and that's probably a cause of the because of the jet stream the large nature of the thunderstorm and some of the effects of the physical forces of the rotation of the earth. I'll begin that rotation. It appears that the rotation begins in the mid levels of the thunderstorm up maybe around 20 or 30,000 feet and as the air flows into the thunderstorm faster and faster. It's the same principle almost as a skater who spins and as they pull their arms in they spin faster and faster. It's called the conservation of momentum and that begins to spin the column of air faster and eventually it works its way down toward the ground and when it touches the ground at then becomes a tornado, there's also another theory and a strong one right now, which which looks very promising and that is As in the lower levels of the atmosphere you get these rotating. They're actually rotating in a horizontal Direction that's caused by the change in wind direction as you go up in the atmosphere called wind shear and if you can imagine like a column that is horizontal to the Horizon under the base of a thunderstorm and it begins to begins to rotate and then what happens is that rotating column gets pulled up into the thunderstorm itself and that helps to induce that rotation along with the are rapidly flowing into the storm. And that may also be a factor in producing a tornado. So those are the kind of things that scientists are looking at now is to the actual cause of tornado formation (00:42:37) concentrating on winter weather today with Jim Campbell meteorologist in Chief of the Twin Cities Office of the National Weather Service next question. Hello, you're on the air (00:42:46) our backyard in a typical radio weather report when you think of the factors the numbers that are transmitted to Listener as a pedestrian and if I'm planning tomorrow's activity and cold winter weather days, then I think that the one that helps me most is the predicted wind chill as whether there is a change in directions of the wind and if we're going to get a Clipper from Canada Northwest winds seem to get stronger and produce more misery and if it shifts around that the Gulf Air is coming up the Mississippi, then we're liable to have different things and among the typically 12345 reported factors in numbers. The dewpoint States me as to what help that can be in planning tomorrow's activities. (00:43:53) Well, the we generally now we include temperatures and winds and Sky conditions and any chances and what kind of precipitation would be in depending on what the most important thing. We try to highlight their sometimes we highlight the wind. Sometimes we highlight the precipitation. We don't generally put dew points in the forecast. We do put it on the hourly weather. What what's important about the dew point especially during the summer months. The dew point is a measurement of the amount of moisture in the atmosphere and the higher the dew points the more uncomfortable that it becomes. So in the summertime when you start getting dew points up in the 60s and especially up in the 70s, it becomes very very uncomfortable the humidity gets very high and we would try to highlight not maybe the number dew point itself, but the fact that there would be high relative humidities or it would be very uncomfortable in the forecast the next day dew points in the wintertime. Although its standard procedure that we use them. They probably Don't have a great amount of usefulness. They do show you know, how dry the atmosphere is if the temperature is 20 degrees and the dew point is zero. It just an indication that the air is pretty dry that that is over us and that's about all that it will tell you during during the summer or during the winter months is how dry things are (00:45:13) five minutes left here with Jim Campbell and we'll turn to your question. Now where you calling (00:45:16) from. I'm calling from Hudson. I have a pet peeve against the weather service and all the radio and TV stations in the cities. The one reason is because that they don't give the downtown temperature in Duluth. I think that's a very bit of interesting information because I've seen that is a difference is much as 40 degrees and I think if they were if they give it information in the summer and in the winter, it would help I think the tourism up in in Duluth, which would also help the state of Minnesota. Thank you. (00:45:51) Okay that it's an interesting comment. Because there is quite a change the temperatures the official temperatures that that we give our taken at the airport, which of course is is away from the lake and is away from the downtown area. So those temperatures at the airport tend to be a little bit warmer in the summer time and probably a little bit colder during during the winter time. There are some Coast Guard stations, I think but there are no official weather service stations that we have besides the one at the airport. And generally we were limited by the number of stations. We have a lot throughout the state of Minnesota and because of the length of our products and things like that. We are somewhat limited that we can't report every temperature that that exists in the state and probably we tend to course to focus on those that are done by weather service stations and some of the flight service stations which again are official stations around the state and where the instruments are calibrated so that probably accounts for some of that (00:46:52) temperatures can vary Widely, even across the Minneapolis st. (00:46:54) Paul area. Oh, yeah. Yeah, they tend to be I know just I live out in the western suburbs and low temperatures at my house tend to be three four degrees colder during the wintertime than they are than they are at the airport and there is quite a bit of variation (00:47:08) right? Another question here for Jim Campbell as we come down near the end of the are. Hello. You're on the air. (00:47:11) Yes. Good morning. My name is Bill wrath muffin. I live in st. Paul. Good morning. Mr. (00:47:16) Campbell morning. I (00:47:17) have a question regards to the cold weather that we're having. I understand from an article. I read recently in the st. Paul Pioneer Press that because we are having a limited amount of snow this winter that the temperatures are causing the frost in the soil to go down deeper than normal and that this could cause a problem with pipes and a water pipes. I was wondering if there's anything that you could add to (00:47:44) that. Well then yeah we yes it is true that because of the lack of snow cover. The frost levels have become deeper be Mainly because the snow acts as an insulating property on the surface, if you have a good snow cover the temperature outside, maybe 10 below zero, but at the at the surface of the between the snow and the ground right down at the ground level it may be, you know closer to freezing or only a little below freezing because it is such a good insulator. I imagine that really depends more on how deep the pipes are buried in the ground. I think there have been some instances here in the Twin Cities where they have been some breaking of water pipes because of that now that we do have a little snow cover and the temperatures are a little bit warmer at the moment. That's probably going to prevent the levels from going much deeper. So unless we get some real cold weather and lose our snow cover. We're probably okay for the Western winter. (00:48:39) We're getting a little bit of a warm up here over this weekend and into the next couple of days. Do you think that the ice is safe on the Lakes? (00:48:48) They I think it's getting to the point. It should be with the we with a All that we had in December and of course, it melts a little bit slower slower than it did when it takes it to freeze up. I would think that I that most of the lakes are still safe temperatures have been staying below freezing. We you know, we've had a couple days when we got above freezing and it's only like two or three degrees so that that's not going to have a large impact on melting the ice on the Lakes. All (00:49:12) right about less than a minute one. Quick question one final one. Go ahead, please you're on. Hello there quickly. (00:49:21) My name is Roy from Ximena Sota. I was warning what effect the Laurentian divide has over whether in northern Minnesota or any area except here on the range of it does affect the what (00:49:36) about 20 seconds Jim? Okay, the fact that you get a little bit rise in the in the land can make a difference in increasing the snowfall and precipitation probably just slightly. (00:49:47) Well Jim, thank you very much. It's been most interesting as always Jim Campbell chief of the National Weather Service Office in the Minneapolis st. Paul area in visiting with us today about winter weather and I suppose that will twist your arm to ask you to come back again sometime in June or July and talk about summer always glad to do it Bob. Thank you so much. Jim quick reminder that. Midday is made possible by Echo lab Incorporated and it's Chemlawn subsidiary coming up now on a minute before 12 o'clock. This is Bob Potter.