NWS Forecast Discussion
626
FXUS63 KMPX 151137
AFDMPX
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
637 AM CDT Wed Jul 15 2026
.KEY MESSAGES...
- Dangerous heat wave continues this week. This is a long
duration and cumulative threat due to daily highs in the
90s, heat indices approaching 100 degrees, and little relief
overnight.
- An Air Quality Alert remains in place for much of northern
through east central Minnesota into western Wisconsin
through Thursday due to an expected plume of heavy smoke
moving south along frontal boundary.
- No precipitation expected until Friday at the earliest, and
mainly for western Wisconsin with low chances at that.
&&
.DISCUSSION...
Issued at 304 AM CDT Wed Jul 15 2026
The forecast continues to run very similar from previous days
for the WFO MPX coverage area with highs in the lower 90s
(potentially as high as 95 in the TC metro counties) and a
nearly cloudless sky. This is due to surface high pressure
remaining anchored over the mid-upper Mississippi River Valley
and the apex of 500mb high pressure ridging (again reaching
600dam per the 15/00z MPX RAOB) sitting over the region. Surface
analysis does show the west-to-east quasi-stationary frontal
boundary sitting over ND into northern MN into the Great Lakes,
with actual showers/t-storms dotted along it for northern MN.
This wouldn`t necessarily be a bad thing to receive
precipitation for northern MN due to the wildfires, however the
additional lightning hazard with dry antecedent conditions up
north could spawn additional wildfires, which is now going to be
a hazard for our portion of MN and WI. With upper level flow
dragging the wildfire smoke southeastward into our coverage
area, and even the slogging southward progression of the
aforementioned front aiding in bringing smoke our way, air
quality will be impacted thus the issuance of the Air Quality
Alert for much of our central-eastern portions of our coverage
area. There continues to be some wobbling in the placement of
the front, particularly how far south it may come, which would
determine how far south the smoke will ultimately reach. While
there is high confidence on precipitation remaining away from
our coverage area through Thursday, and even Friday for most of
the coverage area (only western WI has small chances for
precipitation), the coverage and depth of smoke becomes a
serious wild card for what happens with temperatures, and thus
the intensity of heat impacts. There was some thought to
extending the heat headlines out through Friday with highs still
in the mid 90s and a small uptick on dewpoints due to the
expectation that the front will lift back north on Friday.
However, with such uncertainty to how the smoke will impact the
area today and tomorrow, have held off any adjustments to the
heat headlines at this time and will allow time to monitor
observations both at the surface and aloft.
Still, the ongoing precautionary message remains: Regardless of
if there is a headline out for a given county or of what type,
the hazards of and precautions for excessive heat and air
quality need to be recognized and accounted for. As noted in
previous discussions, continue to practice Heat Safety, but now
accounting for air quality as well: Stay hydrated, check on the
elderly, immunocompromised, and those without A/C, check the
backseat of the car, and limit time outdoors.
While Friday may produce a weak few isolated showers/t-storms
over western WI in association with weak isentropic lift due
to the nearby front, the area will still be dominated by the
broad upper level ridge. However, the ridge will retreat
westward late Friday into the weekend, and then collapse going
into early next week. This will not yet result in a widespread
airmass change, thus highs will still reach the upper 80s to
lower 90s over the weekend with no precipitation expected. The
modest pattern change looks to come Monday onward as a large H5
low looks to drop southward from northern Hudson Bay, allowing
for a more western ridge/eastern trough pattern for the CONUS
early-to-mid next week. This will result in highs falling back
to the lower 80s while also having small increases in
precipitation chances as weak mid-level disturbances round the
fringes of the upper level low. This wouldn`t be enough to bring
soaking rains or mitigation for drought conditions, but it
could produce some showers/t-storms here and there.
Nevertheless, the break from day after day of the elevated heat
would certainly be welcome going into late July.
&&
.AVIATION /12Z TAFS THROUGH 18Z THURSDAY/...
Issued at 636 AM CDT Wed Jul 15 2026
Areas of MVFR/IFR dense fog will continue to mix out over the next
couple of hours. Hence added tempo groups for any near-term vsby
impacts. Winds forecasted to be light and variable through the
period. Main concern remain the impact of wildfire smoke that will
be advecting in from the northeast this afternoon. Smoke guidance
continues to keep greater visibility impacts north and east of
our sites however models have supported MVFR for vsby for STC,
RNH, EAU and MSP. AXN could see smoke as well but given the
site`s proximity to the smoke axis, decided to keep in VFR for
now. MKT and RWF continue to appear smoke free per latest
guidance. Smoke will linger into the next period however expect
VFR vsby to return by late evening. Another shot at MVFR/IFR fog
will be possible tomorrow morning.
KMSP...Maintained mentions of MVFR 5SM visibility for wildfire
smoke mainly between 22 and 05z timeframe. Smoke will likely
linger into the next period however anticipate VFR 6SM or more
returning closer to midnight.
/OUTLOOK FOR KMSP/
THU PM...MVFR vis w/FU. Wind SW 10-15 kts.
FRI...VFR. Wind SW 10-15kts.
SAT...VFR. Wind N 10-15kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...Extreme Heat Warning until 9 PM CDT Thursday for Anoka-Benton-
Blue Earth-Brown-Carver-Chippewa-Chisago-Dakota-Douglas-
Goodhue-Hennepin-Isanti-Kanabec-Kandiyohi-Lac Qui Parle-
Le Sueur-McLeod-Meeker-Mille Lacs-Morrison-Nicollet-Pope-
Ramsey-Redwood-Renville-Rice-Scott-Sherburne-Sibley-
Stearns-Stevens-Swift-Todd-Washington-Watonwan-Wright-
Yellow Medicine.
Heat Advisory until 9 PM CDT Thursday for Faribault-Freeborn-
Martin-Steele-Waseca.
WI...Extreme Heat Warning until 9 PM CDT Thursday for Barron-
Chippewa-Dunn-Eau Claire-Pepin-Pierce-Polk-Rusk-St. Croix.
&&
$$
DISCUSSION...JPC
AVIATION...Dunleavy
NWS MPX Office Area Forecast Discussion