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FXUS63 KMPX 230847

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
347 AM CDT Wed Oct 23 2019

.SHORT TERM...(Today through Thursday)
Issued at 328 AM CDT Wed Oct 23 2019

Confidence remains high that a band of rain will move along I-90
later today. A few snowflakes could mix in at times, but little if
any accumulation is expected. This precipitation will quickly move
east, and cool air will overspread the region keeping temperatures
below normal for Thursday under mostly cloudy skies.

Early morning satellite imagery showed a shortwave trough over the
Dakotas, with clouds and precipitation ahead of it. This trough
will strengthen and take on a negative tilt as it move over
Minnesota and Wisconsin later today. A band of frontogenesis will
lead to an area of enhanced ascent, and this should produce a
fairly steady band of precipitation. Thermal profiles show sub-
freezing temperatures everywhere except the boundary layer, so
thinking is that this heaver precipitation should cool the lowest
levels of the atmosphere enough that a few snowflakes will mix in
along I-90. This precipitation will fall during the afternoon, so
little if any snowfall accumulation is expected. HiRes models seem
to agree with this conceptual model as the Ptype output does show
snow falling across the aforementioned area. There is also a 
chance for a few sprinkles across the rest of the forecast area 
later this afternoon during peak heating.

Looking ahead to Thursday, cold air advection will continue so
expect northwest winds and cool temperatures. Forecast soundings
show a thin layer of stratus, so have increased cloud cover above
the forecast guidance for Thursday.

.LONG TERM...(Thursday night through Tuesday)
Issued at 328 AM CDT Wed Oct 23 2019

The extended forecast shows more of the same. Cold northwest flow
is the predominant regime. There is a brief chance to southerly
flow Friday and Saturday, which should bring some warmer
temperatures, but that reprieve does not last long as another 
cold front pushes though Saturday night.

Confidence is low in the forecast for Sunday and early next week.
There will be a strong temperature gradient from Texas up through
the Great Lakes, with a upper level trough over the Central Conus.
This will set the stage for cyclogenesis, but the timing and
location is very uncertain since there are several moving parts
that need to come together. For now just continued with the
blended guidance, and look forward to better agreement with
subsequent model runs.  


.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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