GREAT LAKES WEATHER: An Active Week/Christmas weather...

15 December 2011

An Active Week/Christmas weather...

500-mb winds showing a decent trough over the western Great Lakes region at this time. 500-mb winds around 100-kts over western half of the forecast region. A short wave of low pressure is making its way into North Dakota this morning and this will reach the region by late tonight, allowing for clouds to hang around in the region. Cold front trying to push into the western half of the region this morning, still over in Illinois as of the 09z charts, following it now on ASOS’s. 300-mb winds confirming the trough, along with a jet streak over the western half of the region. Winds associated with the jet streak are peaking out around 140-kts over the lower half of Michigan. Winds associated with the short wave in the northern Plains this morning are also around 70-100-kts.

850-mb temperature advection this morning showing some decent cold air advection taking place on the backside of this front,

with the main interest being in Omaha, NE. Continuous, although lesser, cold air advection taking place across the northern Plains, indicating some chillier weather – though still in the 30’s – weather headed our way.

High pressure will attempt to build into Plains tomorrow and keep our weather partially calm, that is until our next upper level trough comes out of the Plains. This upper trough will be modest withs track coursing through the region on Saturday. This will introduce some cooler temperatures along with cloudy skies back into the region on Saturday. Another short wave of energy sneaks up behind it and this will help give the eastern half of the region a push for some lake effect snow showers overnight Saturday and into Sunday morning.

Models are in a disagreement this morning with time as the next cold front approaches the region on Monday and Monday night. CMC has it the fastest, while the ECMWF and GFS take a more slower approach to it for Monday. NOGAPS not really liking this system too much, it actually keeps the precip out of the region. The reason for this disagreement this morning is a high pressure which will build up in the southern states over the weekend. This high pressure will be competing for regional dominance of the weather along with the cold front competing as well. GFS also wants to attempt to keep the showers out of the region, but there is a hidden feature that does strike me as interesting a little: the possibility of the front stalling out.

As of now, there is a good chance that this front is going to stall out, however my focus on that will be where it will stall out. We want it to stall out to out to our south, and if this happens the stationary front will extend into the Plains. This is where our next low pressure centre will develop early next week. An upper level low will come out of the southern Plains and help to spawn a surface low along the stationary front. If the front is too our south, like in southern Ohio, then this low pressure will be able to drag down enough cool air that on Wednesday and possibly Thursday to give us a good chance for snow.

This stalling is still about 5 days out, so there is going to be a margin or error. For now, I am going to keep the forecast for Monday night and Tuesday in parts of the region with rain/snow showers as waves of low pressure will ride along the stationary front. Just what form of precip at this point is going to be value of interest.

So will we be seeing a white Christmas this year? Well yesterday sounded rather optimistic, but with the latest model runs and charts I am feeling that the decision of whether or not it will snow before or on Christmas is really going to depend a lot on what happens on Monday. Remember, we need to be on the northwestern edge of this low to see snow. Right now, the possible tracks are doing everything they can to make this unlikely. Cooler weather will be on the way from the low pressure, but the question is going to be will it reach us in time to turn some of the precip into snow. With things going the way they are, Christmas looks to be precip free, but 21-23 December is where the brunt of what our Christmas will look like (weather wise) will be what determines it.

(The past 11 Christmas' in the region).

I’ll have another brief update coming up around 10.00 a.m. here on the site so be sure to check that out. Forecasts are going to be revised throughout the day (mostly Monday and Tuesday forecasts) and if things go well then around Noon I might be able to put a forecast up for Wednesday (which is 21 December). So do be sure to check back for updates. I’ll keep you updated as always, but for now, I am Timmy Albertson and that’s the weather!

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Wednesday forecast

Cleveland: Mostly cloudy throughout the day and overnight. Highs in the mid 40's with overnight lows in the mid 30's. Winds NW at 5-10 mph, shifting to the SE at 10-15 mph this evening.
Erie: Mostly cloudy throughout the day and overnight. Highs in the lower 40's with overnight lows in the low to mid 30's. Winds W-WNW at 5-10 mph, shifting to SE at 10-15 mph this evening.
Toledo: Mostly cloudy throughout the day and overnight. Highs in the lower 40's with overnight lows around 40°. Winds SW at 10-15 mph, gusting to 25 mph, then shifting to SW at 10-15 mph this evening.

http://www.rap.ucar.edu/weather/radar/displayRad.php?icao=KIWX&prod=n0r&bkgr=black&endDate=20110419&endTime=-1&duration=0 Link to regional radar.

Extended forecasts (made at 8.07 wednesday)

CLEVELAND
Tomorrow: Mostly cloudy with rain showers developing in the mid morning and then rain showers likely after noon. Highs in the lower 50’s. Winds S at 15-20 mph with gusts of 35 mph possible.
Tomorrow Night: Mostly cloudy with rain showers likely in the early evening, then becoming scattered before midnight and mixing with snow. Scattered snow showers possible after midnight. Lows in the lower 30’s. Winds becoming W at 20-25 mph with gusts of 40 mph likely.
Friday: Mostly cloudy with scattered snow showers possible in the morning, then scattered snow showers likely throughout the afternoon. Highs in the mid 30’s. Accumulations around an inch or two possible. Winds NW at 25-30 mph with gusts of 40 mph likely in the late afternoon.
Friday Night: Mostly cloudy with lake effect snow showers likely throughout the evening and then lessening up after midnight. New accumulations around an inch or two likely. Lows around 30°. Winds NW at 25-35 mph with gusts of 45 mph likely.

ERIE
Tomorrow: Mostly cloudy with rain showers developing in the late afternoon. Highs in the upper 40’s. Winds SE at 15-20 mph with gusts of 30 mph possible by the late afternoon.
Tomorrow Night: Mostly cloudy with rain showers likely throughout the evening, then becoming scattered and mixing with snow after midnight. Scattered snow showers possible towards sunrise. Lows in the lower 30’s. Winds W at 20-25 mph with gusts of 40 mph possible.
Friday: Mostly cloudy with scattered snow showers possible in the morning, then lake effect snow showers likely throughout the afternoon. Highs in the mid 30’s. New accumulations around an inch or two possible. Winds NW at 25-30 mph with gusts of 40 mph likely in the late afternoon.
Friday Night: Mostly cloudy with lake effect snow showers likely throughout the night. New accumulations around an inch or two likely. Lows around 30°. Winds of 25-35 mph with gusts of 45 mph likely.

FORT WAYNE
Tomorrow: Mostly cloudy with rain showers likely throughout the morning and early afternoon. Rain showers becoming scattered in the late afternoon. Highs around 50°. Winds S-SW at 15-20 mph with gusts of 35 mph likely.
Tomorrow Night: Mostly cloudy with scattered rain showers likely in the early evening, then mixing with snow in the evening and becoming all snow before midnight. Scattered snow showers possible overnight. Lows in the lower 30’s. Winds W-WNW at 20-25 mph with gusts of 40 mph possible after midnight.
Friday: Mostly cloudy with scattered snow showers and flurries possible throughout the day. Highs in the lower 30’s. Winds NW at 25-30 mph with gusts of 40 mph likely by the late afternoon.
Friday Night: Mostly cloudy with scattered snow showers and flurries possible in the evening, otherwise lingering flurries after midnight with a low in the mid to upper 20’s. Winds NW at 20-25 mph with gusts of 40 mph likely.

TOLEDO
Tomorrow: Mostly cloudy with scattered rain showers developing in the early morning, then rain showers by noon. Highs around 50°. Winds S-SW at 15-20 mph with gusts of 35 mph possible.
Tomorrow Night: Mostly cloudy with rain showers becoming scattered in the early evening, then mixing with snow in the evening. Scattered snow showers possible after midnight. Lows in the lower 30’s. Winds becoming W at 15-25 mph with gusts of 40 mph possible after midnight.
Friday: Mostly cloudy with scattered snow showers likely in the morning, then lingering scattered snow showers and flurries possible throughout the afternoon. Highs in the lower 30’s. Winds NW at 25-30 mph with gusts of 45 mph likely by the late afternoon.
Friday Night: Mostly cloudy with scattered flurries possible throughout the overnight. Lows in the mid 20’s. Winds NW at 25-35 mph with gusts of 45 mph likely.