827
FXUS63 KMPX 110812
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
312 AM CDT Thu Jul 11 2024

.KEY MESSAGES...

- The second half of the work week will be mainly dry.

- Hot and humid conditions arriving by the weekend, along with the
return of thunderstorm chances.

&&

.DISCUSSION...
Issued at 309 AM CDT Thu Jul 11 2024

Surface observations and satellite have shown areas of fog
developing overnight across the MPX CWA. The fog is especially
noticeable on the nighttime microphysics imagery along the Minnesota
River Valley where localized visibilities have periodically dropped
below 1 mile. This fog will burn off as the sun rises this morning,
giving away to a beautiful, warm day. Aside from some haze from
lingering Canadian wildfire smoke in the upper atmosphere, today
will be sunny with highs in the low to mid 80s and light winds.
Temperatures will drop into the low to mid 60s tonight. Friday`s
weather will nearly be an exact copy of Thursday`s, aside from
slightly stronger southerly winds.

A portion of the strong thermal ridge currently over the western
CONUS is forecast to advect eastward into the Northern Plains by
this weekend, setting the stage for some hot temperatures. Highs
Saturday and Sunday are forecast in the upper 80s to lower 90s while
nighttime lows don`t offer too much relief; only dropping into the
mid 60s to lower 70s. Additionally, dewpoints are also forecast to
increase into the mid 60s to lower 70s. This will cause heat indices
to rise into at least the mid 90s for much of MN Saturday afternoon
and most of the southern half of the CWA Sunday afternoon. Thus,
heat headlines, specifically a Heat Advisory, are looking like a
good possibility for at least one day this weekend. Areas of most
concern are currently south-central MN and along the Minnesota River
Valley. Multiple chances for rain are also possible and should
mainly be focused along the periphery of the thermal ridge as it
advects east. Forecast models and past experience suggest a
nocturnal to diurnal pattern of convection. Showers and storms
will be favored to develop along the low-level WAA at night,
moving along the thermal ridge periphery and dissipating by late
morning. A second round of showers and storms would then follow
for mostly the same area late that afternoon and into the
night. The Storm Prediction Center does have a 15% risk area of
severe weather across the northern half of MN into WI Sunday.
Sufficient vertical wind shear overlapping with significant
instability (from hot temperatures and moist dewpoints) could
lead to a very favorable severe weather environment. However,
forecast soundings do show large capping across most of our area
from the very warm 850-700 hPa layer. It will be important to
monitor where the weakest capping and strongest lift trends as
this will likely be where storms occur.

The hot weather could hold on into Monday before forecast models
show a cold front pushing though the area. This should moderate our
temperatures by mid-next week returning them to values similar to
what we saw earlier this week (highs in the mid to upper 70s).

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1217 AM CDT Thu Jul 11 2024

Stuck pretty close to the 00z TAFs for the 06z issuance, with
fog being the main concern now that skies are mostly cleared
across all sites. Fog continues to be focused on those areas
that saw rain yesterday, with RWF/STC/MKT having the best chance
with potential still at MSP/RNH/EAU. Winds remain light and
relatively variable through the early afternoon, becoming
150-180 at or below 5kts. A bit of diurnal cu is possible, but
not much in the way of the afternoon shower and storm activity
that has been present the last few days.

KMSP...Fog being the only minor concern, with a lower chance
than other TAF sites nearby.

/OUTLOOK FOR KMSP/
FRI...VFR. Wind S 5-10kts.
SAT...VFR, chc -TSRA early. Wind SE 5-10kts.
SUN...VFR, chc -TSRA late. Wind SW 5-10kts.

&&

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

&&

$$

DISCUSSION...CTG
AVIATION...TDH