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FXUS63 KMPX 252300
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
600 PM CDT Fri Jul 25 2025

.KEY MESSAGES...

- Quiet weather through Saturday aside from poor air quality
  through this evening due to wildfire smoke.

- Hot and humid this weekend with highs in the upper 80s to mid
  90s and heat indices in the upper 90s to mid 100s on Sunday.

- Unsettled weather resumes late Sunday and lasts through early
  next week with thunderstorm chances. Severe storms are
  possible Sunday night.

&&

.DISCUSSION...
Issued at 159 PM CDT Fri Jul 25 2025

Haze has lifted out of southern MN as southeasterly winds push
this round of wildfire smoke north. Improvement can be expected
across central MN and WI later today and this evening. The
thicker haze/smoke has stunted some CU growth thus far across
east central MN and WI, but as it thins we may see better
development later this afternoon. Temperatures are on track to
reach the mid 80s. Quiet weather is expected tonight. Dew
points will remain in the mid to upper 60s so lows won`t drop
much below 70. Can`t rule out some patchy fog again late, but a
bit more cloud cover should prevent it from becoming as
widespread as this morning.

Richer moisture begins to arrive Saturday across western MN,
but an MCV across the central Plains today is expected to track
east northeast across the mid Mississippi Valley tonight. That
will tend to redirect the deepest moisture with it to the east
and could leave a depressed area of temps aloft in its wake.
Southeast flow from that area may keep temperatures across parts
of southeastern MN and western WI from reaching the upper 80s.
Therefore, while it will still be warm and humid, heat headlines
likely aren`t going to be necessary in those areas. The
exception will be far western MN where thermal ridging will be
advancing in and coinciding with dew points in the mid 70s.
Heat indices there should reach around 100.

The thermal ridging will build farther east for Sunday.
Temperatures shouldn`t be the main story, although the typical
hot areas of west central MN could make a run for the upper 90s
if 925 mb temps of +30C pan out. Rather, dew points of 75 to 80
will be the main driver of dangerous heat indices and WBGTs.
Steep mid level lapse rates and 700 mb temps exceeding +12C
should keep the area capped, so the chance of convective
contamination of the airmass is low. Heat indices are expected
to reach around 105 across southwestern MN where dew points
will be in the upper 70s. The heat indices could be higher if
the air temps exceed the forecasted mid 90s or dew points
eclipse 80. WBGTs in the upper 80s are also possible. An Extreme
Heat Watch or warning will be needed soon, extending northeast
into the Twin Cities metro where criteria is 100.

The ridge will build westward Sunday night while a trough
reaches central Canada. This will turn mid level winds more
westerly and speeds will increase to around 40 kts. Potentially
extreme instability will develop Sunday afternoon, lingering
well into Sunday night. Mesoscale features rippling on the
northern periphery of the ridge should be able to get one or
more MCSs developing Sunday afternoon over the northern Plains
or Upper Midwest. There remains low confidence where and when
these individual complex(es) develop and how far south they will
impact. 700 mb temperatures should be warm and marginally
tolerant of convection. There are a lot of unknowns at this
range. Right now the best chances for impacts are across central
and northern MN.

What becomes of Sunday night will set the stage for Monday. A
boundary will lay out somewhere in the area. Seasonably high
pwats, an extremely unstable airmass, and a strengthening N-S
LLJ later in the day impinging on the E-W boundary could bring
renewed thunderstorm development capable of very heavy rain. The
front should sag a little farther south for Tuesday which
should shunt most of the thunderstorm threat to IA, but spatial
differences in the frontal position warrant continuing low
PoPs.

Cooler and drier air will follow for the rest of the week with
surface high pressure building in.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 600 PM CDT Fri Jul 25 2025

Some lingering MVFR haze this evening from wildfire smoke at WI
terminals. This haze has cleared to VFR across MN terminals.
This remaining MVFR haze will clear later this evening. However
for WI terminals this break into VFR may be brief as patchy
fog/mist is expected overnight. Not expecting dense fog, but
more MVFR visibility is forecast. Once temperatures start to
rise in the morning the fog will clear. For all terminals winds
will generally be in the 5 to 10 knot range from the southeast
to south. Some higher gusts into the teens in western MN.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/
SUN...Chc morning MVFR cigs. Chc P.M. -TSRA. Wind S 5-10kts.
MON...VFR. Chc MVFR A.M. -TSRA. Wind N 5-10 kts.
TUE...VFR. Chc MVFR A.M. -TSRA. Wind N 5-10 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...Heat Advisory from noon to 8 PM CDT Saturday for Chippewa-Lac
     Qui Parle-Stevens-Swift-Yellow Medicine.
WI...None.

&&

$$

DISCUSSION...Borghoff
AVIATION...NDC