GREAT LAKES WEATHER: Calm...system...calm?

10 December 2011

Calm...system...calm?

The forecast for today and the start of the week will be rather calm, despite a few lingering snow showers in the Erie area this morning. The high pressure is building up in the region, the upper trough is just passing through the eastern half of the region right now – a few hours earlier than expected, but nothing that would change the forecast. The ridge is now flowing into the region and this is going to be the calm and cool weather that we’re going to see in the region today. Now we do have another system that I am watching, and this one will be interesting – in a way

The high pressure is going to dominate the regional weather over the next couple of days, but it won’t last forever. Towards the morning tomorrow the high pressure will start to slide off to the east, and that will usher in some warmer temps from the south which will gradually warm us up over the next couple of days.

On a side note, this chilly weather – though normal – also hurts the cool temperatures in a way. Typically, when we see a burst of chilly air like this, the cool air mass actually exhausts itself. This means that the cool air masses to the north have to re-energize themselves (for lack of a better term) and that could normally take up to about two weeks. So this chilly weather will not be coming back for at least the next week. This is evident in the mid range models this morning, as they are keeping temperatures rather mild. Happens a bit during the first half of winter.

As this high pressure slides off to the east and the temperatures begin to warm, our focus will shift down to the southern Plains where a long upper level trough will move out of the southern Rockies and emerge down around Texas by the time Tuesday/Wednesday rolls around. This is going to spawn a surfacce low pressure that will develop along the base of the Rockies. At this point, there is a little uncertainty of the exact locations for the centre of the low, but for right now we’ll keep it at the Texas/Oklahoma panhandle.

While the upper level winds become a straight west-east course, the trough will dig further into the Plains and the surface low will deepen. Right now the ECMWF is the fastest of the four models that are being used (ECMWF, GFS, CMC and NOGAPS) but that is only faster by about 12-hours.

The low pressure will have a cold front to its south and warm front to its north and east. Just how far to the east the warm front will extend is also a little on the blah side. The temperatures ahead of the low will be noticably warmer – possibly getting the mid 40’s by Wednesday for some of us in the region – and that will actually make a good portion of the precip rain. Not seeing anything in the 850-mb level that would really make this a snow event, sad when you think about it because we were doing so well with the cooler weather.

Low pressure makes a sharp course towards the region and it looks like it’ll actually stay just off to the west of the region, which as we’ve become accustomed to, means rain.

Low pressure passes through late Thursday/early Friday (hence some uncertainty with the temperatures for Thursday) and this will drag the cold front through no later than Friday morning.

(GFS look at Thursday morning)

Then the high moves towards us…

Now this isn’t to discourage you, because right behind that low pressure, by about 2 days or so, will be a well defined upper trough which will spawn some low pressure centres over along the eastern states. This trough will be with a surface high pressure, which according to our models this morning is going to be a decent sized one on Saturday. This high will pour in down from the northern Plains and head towards the Midwest. This is going to drag the 540-mb line over the region (typically the realm of snow) and the 510-mb line (typically the realm of chilly air) near to the region over next weekend. Further forecasting on this will be made, seeing as how it could give some lake effect snow.

Due to the calm weather for today there will be no 10.00 a.m. Post, but I will be working on those extended forecasts throughout the mornning and those will be updated around 10.00 a.m. Full update around 4.30 p.m. this afternoon. I’ll keep you updated as always, but for now, I am Timmy Albertson and that’s the weather! Keep checking back for updates because I’ll have them for you as always.

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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.