National Weather Service Twin Cities Area Forecast Discussion

Data Provided by the National Weather Service

000
FXUS63 KMPX 021102
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
602 AM CDT Mon Aug 2 2021

.UPDATED for 12Z Aviation Discussion...
Issued at 600 AM CDT Mon Aug 2 2021


&&

.SHORT TERM...(Today through Tuesday)
Issued at 412 AM CDT Mon Aug 2 2021

An unseasonably amplified pattern is taking shape over North America
with a strong ridge over the Rockies and a broad trough over the
Great Lakes region/E CONUS. This places MN and WI in northerly flow
aloft and that will keep us dry for the short term period. At the
surface, high pressure sprawls across the northern plains and upper
MS valley will build eastward today. No obvious sources for
impactful wx in the short term other than smoke/haze/air quality.
The caveat being the shortwave trough sliding through WI this
evening. Isolated showers may develop to our east where slightly
better forcing is expected. An unfavorable environment and a drier
trend in the CAMs prompted the removal of slight PoPs across our far
eastern forecast area.

Another pleasant day is in store for us. Mostly sunny skies becoming
more hazy this evening and high temperatures in the lower 80s and
upper 70s. Dew points remain low so humidity will not be a concern
today or Tuesday. HRRR Smoke (near-surface and vertically
integrated) show conditions deteriorating this evening and tonight
as some sfc smoke currently over western MN spreads east. Elevated
smoke also returns later today as northerly flow brings another
batch southward out of Canada. Tuesday will be similar to Monday,
but with warmer temperatures in the lower to mid 80s and some
lingering smoke/haze aloft.

.LONG TERM...(Tuesday night through Sunday)
Issued at 412 AM CDT Mon Aug 2 2021

A pattern shift is in the offing for midweek and beyond. The trough
will shift southeast and allow ridging to build into the Plains and
Upper Midwest early in the period. A trailing cold front from a short
wave trough in Canada may allow some showers or storms to develop
Thursday. Better chances, along with increasing heat, will follow for
late week into early next week. An initially potent and compact short
wave trough will eject eastward across Wyoming into the northern
Plains and Minnesota/Wisconsin by Saturday. The wave will weaken as
it makes the trek eastward, so confidence isn`t particularly high
with the severe threat. However, a localized maximum of westerly mid
level flow and the presence of a 30-40 kt southwesterly low level jet
could allow the development of organized thunderstorms. The best
chance for severe storms will be associated with a larger and
stronger short wave trough Sunday, although the best chance will be
across the northern half of Minnesota. Stronger mid level flow and
deeper moisture will arrive. Robust instability is expected due to
increased surface dew points, possibly in the 70s, and rather steep
mid level lapse rates in excess of 7.5 C/km.

Temperatures will average above normal through the period. Saturday
is likely going to be the coolest day due to early day thunderstorm
activity. With the Sunday shortwave remaining well to the north,
southwest flow should continue into early next week. This may allow
the ridge to build further across the eastern half of the country,
along with a return to hot and humid conditions with highs in the
90s.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 600 AM CDT Mon Aug 2 2021

Main concern for today will be the potential for more wildfire smoke
impacts. HRRR smoke guidance indicates the potential for vsby
reductions this evening as another batch of smoke pivots southward.
Based on current trends I decided to keep all locations VFR
throughout the TAF period. High pressure will drift eastward
throughout the day, setting up southwest flow setting up for Monday.
We`ll have to watch how the obs trend with respect to the surface
smoke.

KMSP... No additional concerns.

/OUTLOOK FOR KMSP/
Tue...VFR. Wind SW 5-10 kts.
Wed...VFR. Wind SW 10-20 kts.
Thu...VFR. Wind SW 10-20 kts.


&&

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

$$

SHORT TERM...BPH
LONG TERM...Borghoff
AVIATION...BPH

NWS MPX Office Area Forecast Discussion