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fxus63 kmpx 212101 cca 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
223 PM CST Thu Nov 21 2019

Short term...(this evening through Friday night)
issued at 222 PM CST Thu Nov 21 2019

Low pressure continues to move east across the Great Lakes, with only
a few flurries lingering across portions of west-central Wisconsin
early this afternoon. Stratus continues to erode quickly this
afternoon as high pressure building into the region brings in
cooler and drier air, with clear skies expected across the majority
of the County Warning Area by this evening. The tight pressure gradient between the
approaching high and departing low, as well as strong low-level cold
air advection has allowed for northwest winds gusting over 30 mph at
times today. These gusts will begin to diminish into this evening as
the pressure gradient diminishes across the region, but still expect
winds to remain around 5-10 mph through the overnight hours. The
lack of calm winds will keep temperatures from really plummeting
overnight despite the clear skies and dry high pressure overhead.
Expect lows to range from the low teens across central Minnesota
and northwest Wisconsin to near 20 along I-90.

A pleasant day is expected Friday with sunny skies and light winds,
although temperatures will remain cool with highs remaining in the
30s. Winds become southwesterly through the day on Friday, which
will keep temperatures Friday night a few degrees warmer with lows
falling into in the 20s.

Long term...(saturday through thursday)
issued at 222 PM CST Thu Nov 21 2019

The main change in the extended period is that confidence has
increased that no big storms will affect the upper Midwest through
Wednesday of next week.

First, models are slowly becoming more in line for any system that
moves across the middle of the nation will be far enough south to
not impact our region. The split flow regime has played havoc on
individual model runs, and this will likely continue until the mean
upper flow becomes more amplified next week.

There is still a very low chance of light precipitation affect the
region Sunday night/Monday, but even this period remains very
uncertain due to limited moisture availability.

As said before, split flow regimes play havoc on individual model
runs, especially considering if the model is more affected by the
southern stream, vs. The northern. Both the GFS/ec are similar on
taking the bulk of the upper level energy associated with the
southern jet, farther to the south across the southern tier of the
nation early next week. There will likely be phasing issues as the
southern/northern jets merge early next week. But, the thermal
boundary should be far enough south to leave our region uneventful
through Wednesday. A weak surface trough diving south late in the
weekend will only drop temperatures a few degrees, but the
atmosphere will dry out even further before the upper Midwest can
recover as the next system begins to affect the region by late in
the week.

Over the past two days, the mean upper trough that is forecast to
dominate the western 1/4 of the nation next week, will likely begin
to buckle the flow downstream. This reaction to the deep trough out
west, will lead to an upper ridge building across the mid section of
the nation late next week, or around the Holiday. As the flow
becomes more southwest, much milder air will move back northward. At
this time, it is too early to tell if the atmosphere will be cold
enough to produce mostly snow as this system moves out of The
Rockies. Current models have the surface low too far west to allow a
predominately frozen precipitation regime. However, this is
something to think about as we head into next week, and whether
another big storm affects the region Post-Thanksgiving, vs, pre-


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1152 am CST Thu Nov 21 2019

Light rain/snow has exited all terminals except for eau, where it
is expected to end by mid-afternoon. MVFR ceilings will gradually
scatter out though the afternoon, with an improvement to VFR
expected across western and central Minnesota by late afternoon,
and eastern Minnesota/west-central Wisconsin by early this
evening. Northwest winds around 15-20 kts with gusts up to 30 kts
will continue into this evening, before diminishing overnight.
VFR conditions will continue through he rest of the period with
winds gradually becoming southwesterly tomorrow morning.

Kmsp...pushed back the clearing to VFR conditions by a few hours,
with VFR conditions now expected by 23-00z.

/Outlook for kmsp/
Sat...VFR. Wind west 5-10 kts
sun...VFR. Wind west 5 kts


Mpx watches/warnings/advisories...


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