Office: MPX
FXUS63 KMPX 121917
AFDMPX
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
217 PM CDT Sat Jul 12 2025
.KEY MESSAGES...
- Hazardous air quality this weekend from Canadian wildfire smoke.
- Isolated thunderstorms possible Sunday evening. A more
widespread rain event likely Tuesday night - Wednesday night.
&&
.DISCUSSION...
Issued at 216 PM CDT Sat Jul 12 2025
A broad area of Canadian wildfire smoke has settled in across
the Upper Midwest over the past half day. AQI values are at
Unhealthy levels across the state, & may decrease further with
the arrival of another wave of dense smoke this afternoon. While
it's an otherwise pleasant Summer day, it would be best to take
precautions and avoid strenuous outdoor activities & remain
indoors if possible. The smoke will clear out of the area
briefly on Sunday, but another broad area of wildfire smoke
pivots through Sunday evening into Monday per the HRRR near
surface smoke field. An Air Quality Alert remains in effect for
both MN & WI counties through Monday morning.
Sunday afternoon will present a slight chance for an isolated
thunderstorm to develop along a weak surface boundary that moves
through. Storms shouldn't present much impact outside of a brief
shower & a few rumbles of thunder. Wildfire smoke should depart by
Tuesday for those hoping for better air quality. A better chance of
a more widespread precipitation event arrives late Tuesday through
Wednesday night. Guidance highlights a potent shortwave along the
international border on Tuesday & treks eastward through Thursday.
Increasing signal for a broad area of 0.50"+ of rain across the
Upper Mississippi valley region by the end of the work week. We will
dry out with a surface high pressure overhead Thursday & Friday that
should lead to a stretch of cooler than normal temperatures (think
highs in the 70s). Temperatures return to normal next weekend with
another chance for thunderstorms & showers on Saturday.
&&
.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1147 AM CDT Sat Jul 12 2025
Primary concern will be the near-surface smoke this afternoon
through Sunday. Opted for MVFR range visibility at all sites
from the early afternoon hours onward as smoke is expected to
settle across the Upper Midwest through the weekend. Only other
concern is the potential for MVFR-IFR ceilings at EAU where
winds drop off the most while low level moisture becomes caught
under the nightly inversion. Winds turn light & variable
overnight before turning back out of the SW on Sunday at speeds
aob 10kts.
KMSP...Smoke is expected throughout much of the period. Better
low-level mixing may allow for VFR visibility at times, but
prevailing visibility is likely to be in the MVFR range through
Sunday morning.
/OUTLOOK FOR KMSP/
MON...VFR. Wind S 5-10 kts.
TUE...VFR, chc MVFR/-TSRA. Wind S 10-15 kts.
WED...VFR, chc MVFR/-TSRA. Wind NE 5-10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
DISCUSSION...BPH
AVIATION...BPH
Office: DLH
FXUS63 KDLH 121852
AFDDLH
Area Forecast Discussion
National Weather Service Duluth MN
152 PM CDT Sat Jul 12 2025
.KEY MESSAGES...
- Smoke is expected to persist through Monday with perhaps a
brief break for some places Sunday afternoon.
- The next best chances for showers and storms is Sunday night
and again Monday night into Tuesday. Occasional shower/storm
chances the rest of the week.
- Warm weather with highs in the 80s expected Sunday and Monday
with cooler weather into next week.
&&
.DISCUSSION...
Issued at 1245 PM CDT Sat Jul 12 2025
Smoke:
Plenty of haze and smoke is expected through the weekend due to
prevailing west/northwest winds today, becoming southwest Sunday.
Visibilities will be variable as smoke coverage varies, but
generally between 3-6 miles and occasionally down to 1-2 miles while
plumes of smoke continue to advect through the region roughly from
west to east. Air quality alerts are in effect through Monday for
all of Minnesota and Wisconsin. Find air quality information through
Minnesota Pollution Control Agency (https:/www.pca.state.mn.us/air-
water-land-climate/air-quality) and Wisconsin DNR
(https:/dnr.wisconsin.gov/topic/AirQuality).
This afternoon and tonight:
Aside from the smoke, we have a post-cold frontal air mass in place
today and an upper-level trough that will be moving off to the
east/northeast into tonight. Aside from a few showers and perhaps a
rogue thunderstorm in the Arrowhead through this afternoon, dry
weather is expected. Low-level flow will become more west/southwest
tonight with warm air advection developing due to broader ridging to
our west. A weak shortwave will pass through tonight, but with dry
air expected, there shouldn't be any rain with it.
Sunday:
On Sunday, expect warm air advection through the day that will cause
some rather toasty temperatures around the mid 80s pretty much
regionwide. Again, a pretty dry airmass, so maybe a few cumulus
clouds developing, but otherwise just a warm summer day. We might
even get a little break from the smoke Sunday afternoon with
southwest winds pushing it away just for a bit.
Sunday night:
A cold front is then expected to pass through Sunday evening, and as
it does, there could be just enough instability present to promote
some scattered showers and storms, mainly in northwest Wisconsin.
Right now, convective parameters look actually semi-decent for a few
stronger storms (up to 1.5 kJ/kg MUCAPE; 0-6 km shear ~40 kt; PWAT
just over an inch), so we'll have to keep an eye on that, but that
all depends if ingredients come together just right. If there are
any storms, they should be in and out of the region pretty quickly
Sunday night. Lack of synoptic forcing sitting under the right exit
region of a jet aloft (leading to some sinking air) could be an
inhibiting factor. After the front passes, we'll probably see some
more smoke moving in.
Monday:
We get a bit more zonal flow into Monday with some more warm air
advection at/near the surface. So despite a "cold" front, it's still
going to be a warm Monday with highs in the 80s.
Monday night into Tuesday:
Into Monday night, it's looking like we'll get an upper-level wave
passing through with some fairly strong frontogenesis associated
with a cold front that should pass through going into Tuesday. Some
pretty deep moisture with PWATs >1.5" may be possible along with pre-
frontal southwesterly flow aloft that could promote at least some
training potential of thunderstorms that may develop ahead of the
front Monday night. There's a lot of model disagreement with other
convective parameters as the strongest (likely elevated) instability
may not be perfectly aligned with better bulk shear. So in terms of
potential for strong to severe storm potential, confidence is pretty
low at this time. But in any case, we may see some storms Monday
night and into Tuesday with cooler air advecting in from the north.
Wednesday through Friday:
Some cooler air is looking to settle in Wednesday into Thursday.
Some places may see highs only reaching the 60s. A slightly wavy
quasi-zonal flow pattern for a few days may keep rain/storm chances
in the forecast at times through the end of the week.
&&
.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1245 PM CDT Sat Jul 12 2025
Prevailing MVFR conditions through the period at all terminals
due to persistent smoke and haze. HRRR smoke model suggests we
will continue to see plumes of nar-surface smoke passing through
tonight. It's possible there may be a bit of a break with winds
becoming more southwesterly mid Sunday morning around BRD,
temporarily clearing some smoke out. With all regional northern
Minnesota and northwest Wisconsin observations sitting firmly
in the ~1 1/2 to 5 SM range currently and westerly winds
expected to persist today, it seems reasonable that visibilities
should predominantly remain MVFR. It's possible that some mixing
this afternoon could lead to some 6 SM visibility at times, but
perhaps not predominantly.
Aside from smoke, clouds are expected to clear out a bit this
afternoon, so ceilings may scatter to VFR and remain that way
through the period as drier air moves in. Occasional gusts
around or just over 15 kt from the west to northwest today,
decreasing a bit tonight in speed and becoming southwesterly.
Some 15 to 20 kt gusts are expected again late Sunday morning.
&&
.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 152 PM CDT Sat Jul 12 2025
Southwesterly winds are expected tonight through midday Monday.
Winds will strengthen in speed on Sunday, and there is a
~20-30% chance that there could be some gusts up to 25 kt, but
more likely topping out at around 20 to 21 kt Sunday afternoon.
Wind speeds decrease Sunday night and become a bit more variable
in direction with generally light speeds Monday night into
Tuesday. There is a small chance (15-20%) for some non-severe
storms Sunday evening. Additional chances for storms are
expected (30-40% chance) Monday night into Tuesday.
For the open water discussion, refer to the NWS Marquette Area
Forecast Discussion at weather.gov/mqt.
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...None.
&&
$$
DISCUSSION...JDS
AVIATION...JDS
MARINE...JDS
