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FXUS63 KMPX 220339 AAB

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
1039 PM CDT Wed Aug 21 2019

.SHORT TERM...(This evening through Thursday night)
Issued at 245 PM CDT Wed Aug 21 2019

Pleasant, early fall-like, weather continues into Friday as a broad 
trough over the central US keeps seasonably cool temperatures aloft 
over the Upper Midwest, and high pressure at the surface ensures dry 
conditions. A chilly night is expected tonight with mainly clear 
skies over the area and light winds. Lows should drop into the upper 
40s across central Minnesota into west-central Wisconsin and low to 
mid 50s elsewhere, although cloud cover streaming off of Lake 
Superior make keep temperatures a few degrees warmer across farther 
east into Wisconsin. Drier northeast flow should keep the boundary 
layer dry enough to prevent much in the way of fog development, 
although typical patchy of fog will be possible along river valleys 
and other low-lying areas.

Nothing to complain about tomorrow weather-wise, with highs in the 
low to mid 70s and light winds. These highs will be close to 10 
degrees below normal for late August. Partly cloudy skies from fair 
-weather cumulus will develop by late morning, with potentially
 more of a cloudy day possible across west-central Wisconsin
 thanks to additional moisture and cloud cover streaming off of
 Lake Superior. Another seasonably cool morning is expected on
 Friday, with patchy fog development possible.

.LONG TERM...(Friday through Wednesday)
Issued at 245 PM CDT Wed Aug 21 2019

The longer term concerns remain timing of incoming western CONUS 
trough over the weekend and continued cool weather pattern. All in
all, looks like a fine start to the Minnesota State Fair.  

Cool high pressure will dominate the weather into Saturday across
the CWA. Highs are expected to remain near or slightly below
normal with afternoon highs in the mid/upper 70s. Dewpoints  
dont return until the weekend as the western CONUS trough builds 
east into the Dakotas and eventually western MN Saturday night. 
Increasing southerly winds on the backside of the retreating high
pressure should lift increasing moisture into the area.

The GFS and ECMWF move the trough east over the area Saturday 
night into Monday. We will hold onto the blended guidance high 
end likely PoP and spread it east Sunday and Sunday night. 
Instability increase ahead of the trough, and there will likely be
some threat of severe weather, especially to the west Sunday. 

The front should exit to the east Monday with a drying trend 
expected into Tuesday. Models diverge some on timing of next 
impulse riding southeast in the developing eastern CONUS trough 
into midweek next week. Will maintain small chance mainly later 
Tuesday into Tuesday night. Following this system, the eastern 
CONUS trough digs south and drops in some very cool air over the 
Great Lakes region. The return of +4C at 850 mb over much of the 
state by the end of the month. 


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1039 PM CDT Wed Aug 21 2019

VFR conditions and clear skies are expected tonight. Some diurnal
CU will develop again Thursday afternoon. 

KMSP...No concerns.

Fri...VFR. Wind SE 5-10 kts.
Sat...VFR. Wind SE 10G20 kts.
Sun...MVFR/IFR possible. PM -TSRA likely. Wind S 10G20 kts.



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