Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 121708

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1208 PM CDT Sun Jul 12 2020

Issued at 1158 AM CDT Sun Jul 12 2020

Updated to include 18z aviation discussion below.


.SHORT TERM...(Today through Monday)
Issued at 404 AM CDT Sun Jul 12 2020

Very few clouds and a light north to northwest wind will prevail
today, and into this evening. Return flow develops late tonight,
and into Monday that is in response to the next storm system
moving across the Pacific northwest early this morning. Although
thunderstorms will likely develop across far western Minnesota
Monday afternoon as strong ascent develops ahead of this Pacific
northwest storm, the bulk of the active weather will occur after 6
pm Monday.

.LONG TERM...(Monday night through Saturday)
Issued at 404 AM CDT Sun Jul 12 2020

Strong height falls will overspread the area late Monday as a
trough progresses east and digs into the northern Plains and Upper
Mississippi Valley. Through most of Monday the atmosphere looks
well capped, but as heights continue to fall, moisture increases
quickly, and the low level jet increases early Monday evening,
thunderstorms should begin erupting over the eastern North Dakota
and northwest Minnesota. They will build southward with time into
southern Minnesota. Initially these storms could be discrete and
all severe hazards would be possible, including tornadoes
(especially across northwest MN where storms could develop as
early as Monday afternoon). Given mid level flow parallel to the
boundary, these storms should grow upscale into a QLCS or clusters
later Monday evening. A slow moving cold front and storm motion
more or less parallel to it brings a concern for heavy rainfall
and flash flooding. Highest risk for this would be from southwest
and east central MN into northwest WI late Monday night. The front
will continue southeastward Tuesday with PoPs gradually
decreasing behind it. Models have slowed the frontal passage from
earlier runs, so PoPs have been shifted later in time from the

Dry weather will return Wednesday and Thursday under the influence
of high pressure. By Thursday night, a warm front will be lifting
north across Nebraska and Iowa with a LLJ impinging on the front.
Thunderstorm development is possible late Thursday night and could
continue into Friday.

Models differ how far north the warm front will get Friday and
Saturday. GFS is most suppressed, possibly due to an MCS tracking
across the area Friday night. ECMWF and Canadian bring it north of
the CWA and temps Saturday return back to the 90s. The heat would
hang around briefly before a cold front tracks eastward across the
Great Lakes Saturday night.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1158 AM CDT Sun Jul 12 2020

VFR conditions expected throughout this TAF set with passing high
cirrus clouds. Light NW winds will go light/variable then pick up
from the SE on Monday, becoming breezy/gusty by mid-to-late

KMSP...No additional concerns.

Mon Night...RA/TSRA/MVFR likely after midnight. Wind S 10-15 kts
becoming SW 5-10 kts.
Tue...RA/TSRA/MVFR likely, mainly in the morning. Wind SW 5-10
kts bcmg NW.
Wed...VFR. Wind NW 5 kts.




LONG TERM...Borghoff
AVIATION...JPC is the U.S. government's official web portal to all federal, state and local government web resources and services.