Battle of the Air Masses
During the noon show today, I created a simple graphic called the “Battle Of The Airmases”. I did it because over the next 5 days or so, we’re going to have a real fight with trying to accurately pin down the temperature forecasts.
Basically I think we get out of the arctic air tomorrow, go back into it Thursday into early Friday, try and get out of it Friday, go back into it Friday night through Sunday AM and then get out of it later Sunday into early next week. That’s a lot of sloshing back and forth and that’s why the temperature forecasting will be tough. I can’t see how with all this going on there aren’t a lot of clouds at times, and that too will complicate forecasting the weather and somehow there has to be some precipitation…doesn’t there?
Well we are in the drought and the models have been overly aggressive at times generating precipitation, but I wonder if, perhaps something is getting picked on that bears watching for the end of the weekend. The GFS has really been ambitious with this for a couple of days, perhaps overly so as it keys in on a wave moving out of the SW part of the country. There is an upper level storm now in the eastern Pacific Ocean off the coast of CA and Mexico that the model has grabbed onto in a big way for Sunday.
The GFS grabs onto the wave and keeps it together has it moves through the Midwest. The EURO on the other hand weakens the wave substantially BUT what both models are doing is generating some precipitation which, combined with the arctic air moving out and a return of some gulf moisture has me wondering IF maybe something “interesting” can happen later Saturday into Sunday AM…what form the precip would take and how much of whatever falls are still questions but lets start thinking about that. There would be the potential for some sort of wintry mix that bears watching.
So that has got me entertained this afternoon, but to be honest when I start speculating on something that’s 5 days away, during this time of the year, I’m not really overly confident in how it plays out and it’s probably a sign that I really am getting bored.
So with that said, I decided today to look at various satellite pictures to see what I can teach you about the weather today and I decided to take a look at the Great Lakes area. There have been some nice localized lake effect snows going on up there, while not terribly widespread, some areas up there, in upstate NY and W PA have seen close to 3 FEET of snow. Erie, PA set a snow record for yesterday’s date with over 16″ of snow with parts of town getting close to 24″. Here is a satellite photo take today, and I think it shows some neat things that I labelled for you.
The Lake Effect phenomena is pretty neat to go through. They haven’t had that much of it so far this winter, but these cold airmasses coming out of the Canada/Arctic region have been turning on the “machine” if you will. It’s not so much that they are difficult to forecast for, it’s that ANY minor variation in the wind direction, we’re talking 10° of a change (if you’re using a compass) radically changes which part of a county gets the heavier snow. Lake Effect is known for giving one community 2 FEET of snow, and then IF you drive 5-15 miles away…nearly nothing! Tough to forecast that stuff. Here is an image from the NWS in Buffalo showing the processes involved.
One of my more fun trips to N MI was about 5 years ago during the winter and I happened to catch a Lake Effect squall(s) over the course of a few days. It snowed hard and fast. We must’ve picked up about 3-4″ in one hours time. Very cool to see/experience.
So I wanted to bring this up, because not only does this phenomena occur across the bigger Great Lakes area, but it can also occur over smaller bodies of water including the Salt Lake area, the Lake of the Ozarks (I remember that a couple of years ago during our brutal winter of 2009-10 and 10-11) and even ponds. You read that right, yes ponds. Now they have to be decent sized but it can happen immediately downwind of the pond. Smoke stack exhaust (especially from power plants) has been know to generate, not only clouds, but also flakes of snow (since the cold arctic air has a tough time holding moisture). Check this out from the NWS in Chicago yesterday.
So there you go, a classic way that mankind can affect the weather in a very small way at least.
So when does the Lake Effect get turned off for a period of time?. Well simply when the lakes are frozen over. Once that occurs the “warmer” lake water can’t evaporate into the air, since they’re capped with ice. When that occurs the snow is shut down. Right now most of the Lake water is still ice free, but should the cold continue a lot longer, that will change over the next couple of weeks perhaps.
With something potentially there to watch for Sunday, I’ve decided for now to up the FOX 4 Snowfall Potential Index a notch. Also I’m really tired of seeing the same number up there for weeks at a time it seems.