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FXUS63 KMPX 230404

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1104 PM CDT Tue Oct 22 2019

.SHORT TERM...(This evening through Wednesday night)
Issued at 335 PM CDT Tue Oct 22 2019

The back edge of the extensive cloud cover from the departing storm 
system north of the Great Lakes, was across west central, southwest 
and south central Minnesota this afternoon. Temperatures have 
recovered nicely where the sunshine was plentiful today. There 
remains some light rain or drizzle across central/east central 
Minnesota, as well as west central Wisconsin, but this area will 
likely be dry by the late afternoon as most of the deeper moisture 
moves off to the northeast. The main weather element this afternoon 
was the strong/gusty winds. Winds were near 50 mph across 
west/southwest Minnesota with a few gusts still near 40 mph across 
west central Wisconsin today. These winds will decrease this evening 
as the storm system continues to move away from the region. All but 
west central Wisconsin, and parts of east central Minnesota will see 
mostly cloudy skies tonight, with clear skies in the southwest. 
However, this will be short-lived as the next storm system quickly 
moves southeast over the Plains of South Dakota and Nebraska. The 
system in question for tomorrow was forming/developing across 
eastern Montana this afternoon. A nice jet core and isentropic lift 
ahead of the surface low over Alberta Canada, was beginning to 
produces some light rain across Montana. This system will only brush 
our region with some very light snow, or light rain along the Iowa 
border starting late tonight, and into Wednesday morning. Most of 
the precipitation will end by noon Wednesday, but the cloud cover 
will likely hold on. The best moisture advection/isentropic lift and 
jet energy will remain across Iowa so I wouldn't be surprised to see 
little or nothing for snowfall. However, thickness values and 
surface temperatures are cold enough to have the precipitation start 
out as snow, and quickly change over to light rain. If this system 
was a bit stronger, the snow maybe last longer with some minor 
accumulations along the Iowa border. However, at this time based on 
the current trends, this system will continue to weaken as it moves 
across Iowa Wednesday morning.

.LONG TERM...(Thursday through Tuesday)
Issued at 335 PM CDT Tue Oct 22 2019

The long term period looks to be mostly dry, starting off with a 
couple days of sunshine. Temperatures will be below normal Thursday, 
warming into the 50s Friday and Saturday, before a cold front moves 
through the local area Saturday night, brining a surge of cooler 
air across the region.

By Thursday morning, a positively tilted longwave trough will be 
centered from near the four corners region through the Dakotas and 
northern Minnesota. An upper low will develop at the south end of 
the trough, and slowly work across northern Texas and Oklahoma, and 
eventually swing northeast toward the eastern Great Lakes. 
Meanwhile, a progressive shortwave trough and associated surface 
cyclone will move east across southern Canada, brining warm 
southwesterly flow to our area late Friday through Saturday. The 
cold front with this system will sweep through our area Saturday 
night, bringing cooler temperatures into the region for Sunday and 
beyond. Saturday should be our one warmer than normal day, with 
highs in the mid to upper 50s expected. Winds of 10-20 MPH with 
gusts of 25 MPH will make it feel cooler though. With the 
aforementioned system to our south hogging the moisture feed from 
the gulf, expect the cold front will pass through mostly dry across 
our local area.

Another strong longwave trough will sink in across the northern 
CONUS through Monday night, with colder than normal temperatures 
expected to continue.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1104 PM CDT Tue Oct 22 2019

Clouds are starting to break up a bit faster on the west edge, by
the clearing still does not look to make it much farther northeast
of I-94. Strong wave in on its way to Iowa. Most hi-res models
show precip falling along the I-90 corridor, getting about as far
north as MKT, which is the only site that has a chance at seeing
precip Wednesday. Still expect clouds to dive back south as the
Iowa wave moves toward the Quad Cities. They should come back in
as MVFR, though we cloud see some IFR cigs up at AXN. 

KMSP...No huge changes from previous TAFs, 2k-4k foot cigs still
look to return between 19z and 20z.

Thu...Chc MVFR cigs. Wind NW at 5-10 kts. 
Fri...VFR. Wind SW at 10G20 kts. 
Sat...VFR. Wind SW at 15G25 kts.



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