458 
FXUS63 KMPX 031737
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1237 PM CDT Wed Aug 3 2022

.UPDATE...
Issued at 1226 PM CDT Wed Aug 3 2022

Updated for 18z aviation discussion.

&&

.DISCUSSION...(Today through Tuesday)
Issued at 320 AM CDT Wed Aug 3 2022

Key Messages:

1. Building heat/humid on Friday. 
2. Next week uncertainty of how hot it could get. 

Water vapor imagery this morning indicated diffluent flow aloft 
across southern Mn and Wi. This was noted by the strong upper flow 
ahead of the main shortwave moving across North Dakota this morning, 
and weaker flow across the central Plains. Several waves of 
thunderstorms occurred late Tuesday evening, and into early 
Wednesday morning ahead of the main cold front still lagging behind 
across central Mn. There is still a chance of showers and 
thunderstorms this morning before the main cold front moves south of 
our region. Currently, based on the initial movement of the front 
and much drier air behind it, the southeastern 1/4 of MPX CWA will 
see scattered showers and isolated thunderstorms until mid morning. 
By noon, the drier and cooler airmass will have spread southeast of 
our region, limiting any precipitation chances. There is a small 
line of showers across northern Mn this morning, but this is likely 
associated with the shortwave trough which will affect mainly 
northern Mn through sunrise. 

Dew points are expected to drop into the 50s by tonight and hold in 
the 40s/50s until return flow develops late Thursday night and into 
Friday. Thus, a much more comfortable airmass even though 
temperatures will remain slightly above normal. 

Global models continue to support, or at least are more consistent 
with an elongated upper ridge developing across the Rockies, and 
into the Upper Midwest/Great Lakes region by this weekend. A very 
strong jet is noted over southern Canada by this weekend with a cold 
front slowly sagging southward Saturday/Saturday night across our 
region. Friday looks to be another very hot and muggy day with 
afternoon heat indices approaching 100 degrees or hotter. Wet bulb 
global temperatures are in the lower 80s which is high but not 
enough to warrant heat headlines at this time. Friday night and into
Saturday temperature/humidity profiles will be dependent upon cloud 
cover and precipitation chances. Currently, the NBM supports much 
cooler temperatures than in previous forecast as chances of 
precipitation have increased to likely and cloud cover is greater. 

Next week remains uncertain based on the evolution of a persistent 
upper low centered off the west coast of the U.S. The main energy 
and upper level flow across our region has been either northwest, or 
quasi-west/southwest which leads to subtle shortwaves and occasional 
frontal passages. There has been a stronger signal of a longwave 
trough across Alaska, and portions of western Canada next week. This 
may aid into the change for the upper low to slowly get engulf into 
this longwave feature and lift northeast across the Pacific 
northwest region. Ahead of this feature, the upper ridge will 
continue to build across the Rockies and into the Northern Plains, 
and Upper Midwest. This will lead to a much more hotter period is 
this sets up.  

&&

.AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon)
Issued at 1226 PM CDT Wed Aug 3 2022

VFR conditions through the period with mostly clear skies. Northwest
winds will gust around 20-25 kts through sunset and diminish to
around 5 kts tonight. Winds slowly veer from northerly to
southeasterly overnight and through tomorrow morning.

KMSP...Northwest wind gusts around 20-25 kts this afternoon, with a
few sporadic gusts over 30 kts possible.

/OUTLOOK FOR KMSP/
Fri...VFR. Wind S 10-15G25 kts. 
Sat...MVFR/-TSRA likely. Wind N 10-15 kts
Sun...Chance MVFR/-SHRA. Wind N 10-15 kts
&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&

$$

DISCUSSION...JLT
AVIATION...ETA