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FXUS63 KMPX 201145 AAA

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
545 AM CST Wed Nov 20 2019

.SHORT TERM...(Today through Thursday)
Issued at 320 AM CST Wed Nov 20 2019

Extensive cloud cover continues to shroud the region this morning, 
although some thinning and a rapid rise in ceilings is taking 
place across southern Minnesota. The low stratus should lift north
this morning as a ridge builds modestly across the center of the 
U.S., but increasing high and mid level clouds will keep cloud 
cover high through the day. 

Later today, a northern shortwave tracking east across ND will
allow for rain to blossom across central MN. By late this 
evening as a southern system lifts northeast and phases with the 
approaching trough from the northwest, increasing isentropic lift 
will allow rain to develop across the rest of the area. The 
heaviest rain will be found just northwest of the low track where 
the best low level convergence will exist along a cold front. 
Strengthening northwest winds behind the cold front will drop 
temperatures steadily late tonight through Wednesday. Rain will 
gradually turn to snow from west to east during this time. QPF has
decreased across western MN, which has resulted in lower snow 
totals. Farther east into WI, the rain should end before the cold 
air arrives and little or no snow is expected there. The most 
uncertain area is from southwest MN to east central MN where cold 
air will interact with steadier precip. Snow totals will depend 
heavily on when the transition occurs. The earlier it occurs, the 
more snow will accumulate. Luckily, it appears the subfreezing air
will follow the western edge of the precip shield eastward, 
leaving the entire CWA with a forecast that calls for less than an
inch. Of a somewhat larger concern is the potential for a flash 
freeze as temps drop into the 20s during the afternoon.

.LONG TERM...(Thursday night through Tuesday)
Issued at 320 AM CST Wed Nov 20 2019

High confidence continues that modified western Canadian high 
pressure will slide into the north-central CONUS starting Thursday
night behind the departing complex low pressure system. This high
pressure area will result in dry weather for Thursday night
through Monday night along with relatively mild and above normal 
temperatures with highs mainly in the mid 30s to the mid 40s.

Starting on Tuesday and looking beyond, considerable uncertainty
exists as there are multiple solutions on how the mid-to-late week
mid-latitude cyclonic system looks to evolve. On a broad synoptic 
scale, a dry cold front will drop south from western Canada and 
across the Northern Plains on Monday, stalling out from the Great 
Lakes through the TX/OK Panhandle region on Tuesday. Along this 
front, somewhere in the Deep South, a low pressure system looks to
develop Monday into Tuesday then slide northeast along the front,
moving to a position somewhere in the north-central CONUS into 
the Great Lakes around Thanksgiving.

At this point, it is way too early to speculate any specifics with
any kind of confidence due to that there are model solutions all
over the spectrum. Some solutions don't even have a low pressure
system anywhere near the Upper Mississippi River Valley, some have
it to the west, south or east of the WFO MPX coverage area, some 
have it right atop the area. Then there is the diverging solutions
on the amount of moisture, the track of the system, the forward 
speed of the system, and the temperature composition of the system
which would then produce varying solutions for precipitation type
and amount. Since this system is yet 7-8 days away, there will be
multiple changes in the forecast until these divergent solutions
can be resolved with any degree of consistency and confidence.
Then, and only then, can specifics be discussed for precipitation
type and amounts.

Therefore, continue to pay attention to reliable forecast sources,
including the National Weather Service, for the latest information
on any potential large-scale winter systems.


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 545 AM CST Wed Nov 20 2019

The back edge of the MVFR cigs continues to progress
northeastward. At TAF issuance time, it was located roughly from
Long Prairie to Hutchinson and Faribault, MN. IFR or lower
conditions also continue in WI. Conds will improve with time this
morning. Most locations will be VFR this afternoon. Conds will
deteriorate rapidly again this evening as rain blossoms over the

KMSP...Should see another 2-3 hours of MVFR cigs before they move
out for the rest of the day. Rain will move in after 04Z, then
could turn to snow for a short time Thursday morning before

Fri...VFR. Wind W 5 kts.
Sat-Sun...VFR. Wind W 5-10 kts.



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