176
FXUS63 KMPX 141034
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
534 AM CDT Mon Jul 14 2025

.KEY MESSAGES...

- Warm & humid today & tomorrow.

- Thunderstorms expected Tuesday evening through Wednesday.
  Locally heavy rain is likely in addition to a chance for
  severe storms Tuesday evening.

- Additional chances for thunderstorms this weekend into early
  next week.

&&

.DISCUSSION...
Issued at 256 AM CDT Mon Jul 14 2025

Relatively quiet night across the area with a few lingering
showers across western Wisconsin, & the latest surge of Canadian
wildfire smoke remaining limited to northern Minnesota &
Wisconsin. Temperatures will warm a few degrees compared to
yesterday with highs around 90 expected, but strengthening
southerly flow will bring muggier dewpoints by this evening.
This will create a rather unstable atmosphere by this evening
with more than 3000 J/kg of surface-based CAPE expected to
develop, however weak forcing along a diffuse surface boundary
will be tough to overcome capping aloft with 700 mb temperatures
nearing 10 C. One or two isolated thunderstorms can`t be ruled
out however, most likely across western Wisconsin where capping
will be weaker.

Another warm & humid day is expected Tuesday as southerly flow
continues to increase ahead of a slowly advancing cold front
out of the Dakotas. Compressional warming along the front may
boost temperatures into the low to mid 90s across much of
eastern & southern Minnesota & western Wisconsin, while precip &
cloud cover from the front could limit temperatures to the 70s
across central Minnesota. This precipitation during the day is
not expected to be very heavy or widespread, but thunderstorms
will become more robust Tuesday evening as upper level forcing
from a passing shortwave increases. Another unstable
environment will develop ahead of the front by Tuesday
afternoon with 2500-3000 J/kg of surface-based CAPE, but only
around 20 kts of deep shear meaning any strong to severe storms
Tuesday evening will likely be short-lived. Also likely limiting
our severe p[potential will be that the evening precipitation
looks to be largely anafrontal, or occurring behind the surface
cold front, meaning it likely won`t be able to fully tap into
that unstable environment. More concerning is the threat for
locally heavy rain, as multiple rounds of thunderstorms are
expected as the front slowly moves through the area through
Wednesday. The atmosphere will be primed for efficient rainfall
as precipitable water values peak around 2" along the front.
Extended-range high resolution models already depict areas of
3-4"+ of rainfall, highlighting the locally heavy rainfall
potential, but we won`t know exactly where these areas will be
until we start seeing where storms develop tomorrow night. The
good news is that this does not appear to be a classic training
thunderstorm type of set up, more like multiple rounds of slow-
moving thunderstorms that will likely impact a few locations
more than once from Tuesday evening through Wednesday morning.
Outside of those locally-enhanced amounts of 3-4"+, widespread
amounts of around 1.5-2" are generally expected across central
Minnesota, tapering down to 0.5-1" across southern Minnesota.

Precipitation should be exiting the area Wednesday afternoon,
with mostly dry weather expected into Friday as high pressure
passes over the region. Temperatures will be seasonably cool as
well with highs Wednesday & Thursday only in the upper 60s to
low 70s. Still a little too early to have a good handle on the
potential for air quality impacts from additional wildfire
smoke, but at least some smoke in the region looks likely given
the northwesterly flow aloft. The flow aloft becomes more
active this weekend into next week, with a few shortwaves likely
giving us chances for thunderstorms. Blended model guidance
PoPs give us generic ~30% chances for rain during this entire
period, but this is an artifact of timing differences among
models. Thunderstorm chances generally look most likely
sometime Saturday, & then again Monday into Tuesday with near-
normal temperatures.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 529 AM CDT Mon Jul 14 2025

Main change this to the 12z TAFs was to remove the smoke (FU)
mention as the HRRR has really backed off on the surface smoke
concentrations we`ll see across the MPX area. There are some
reduced visibilities out there this morning, but this is just
your standard shallow ground fog. Otherwise, there are few
weather concerns this TAF period.

KMSP...a mix of BR/FU will lead to a hazy sky to start the
period, but as mixing builds this morning, look for the haze to
quickly mix out.

/OUTLOOK FOR KMSP/
TUE...VFR, TSRA/MVFR likely overnight. Wind SW 10-15 kts.
WED...MVFR, chc IFR/-TSRA. Wind NE 5-10 kts.
THU...MVFR early, then VFR. Wind NE 5-10 kts.

&&

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

&&

$$

DISCUSSION...ETA
AVIATION...MPG