327
FXUS63 KMQT 170516
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
116 AM EDT Fri Jul 17 2026

.KEY MESSAGES...

- Smoke from upstream wildfires will continue to impact Upper
Michigan into this weekend. Air Quality Alerts remain in effect
through Friday. Consider remaining indoors when possible.

- An approaching system is expected to bring widespread rain and
scattered thunderstorms to the UP Friday morning through Saturday
morning. A few storms could be strong to severe on Friday.

- There is lower confidence in how Friday`s system will impact
potential smoke concerns going into the weekend.

&&

.DISCUSSION...
Issued at 330 PM EDT Thu Jul 16 2026

Afternoon RAP analysis continues to depict northwest flow aloft over
the Upper Great Lakes on the periphery of an expansive ridge
encompassing much of the central CONUS. This pattern maintains the
status quo over the UP today as dense smoke from the upstream
wildfires over MN and Ontario continues to drift over the Great
Lakes and produce significant visibility reductions and very poor
air quality across the region. Smoke has once again held
temperatures well below guidance, with afternoon highs ranging from
the 60s near Lake Superior to the low to mid 70s elsewhere, save for
a few spots in the low 80s in the far west. The Michigan Dept of
Environment, Great Lakes, and Energy (EGLE) has extended the
statewide Air Quality Alert through Friday given ongoing smoke
concerns over the region.

Confidence continues to increase that the UP will receive a
widespread wetting rain on Friday as the upper level flow pivots
more westerly and paves the way for a shortwave trough to cross the
region through Friday night. Ensemble guidance now depicts a an 80-
95% chance for at least a quarter inch of rain across most of the UP
through Saturday morning, with closer to a 50-70% chance along the
WI border. Some locations could end up seeing much more than a
quarter inch in embedded thunderstorms as PWATS climb back above
1.5" on Friday. Speaking of thunderstorms, SPC maintains a marginal
risk for severe thunderstorms over the UP on Friday, which certainly
appears plausible given bulk shear values increasing above 40 kt.
The wild card will be the degree of instability as smoke continues
to impact surface heating. Regardless, will be on the lookout for a
few strong to severe storms Friday afternoon into Friday evening,
with damaging wind gusts and large hail as the primary threats.

In terms of ongoing smoke concerns, the hope is that expected
wetting rainfall coupled with stronger southerly winds will help to
reduce the amounts of particulate matter and start to mix out the
smoke from the low levels of the atmosphere. Hi-res smoke guidance
seems to bear this scenario out as it depicts greatly reduced
concentrations of smoke during the day on Saturday. Still, much of
this will depend on how the incoming system impacts the upstream
wildfires to hopefully limit smoke production going forward, as
returning northwest winds will otherwise remain conducive to smoke
drifting over the region if those wildfire areas do not receive
appreciable rainfall. Will continue to closely monitor these
developments in the coming days.

Aside from the lingering questions about smoke, the forecast
otherwise looks relatively benign through much of next week as the
region settles back into northwesterly flow with temperatures near
seasonal norms. There is increasing confidence in another system
bringing another shot of rainfall to the area next Monday.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 115 AM EDT Fri Jul 17 2026

IFR vsbys continue due to wildfire smoke, and expect that to
generally continue into this morning. There is potential for vsbys
to improve at least to MVFR by this afternoon/evening as winds
attain a southerly component and increase modestly along with
diurnal mixing, but confidence in that is low. The other
consideration is thunderstorm potential. An isolated TS cannot be
ruled out in the 10-16Z timeframe, but potential too low to include
in the TAFs. Somewhat better potential outlined by PROB30 groups
during the afternoon and evening hours, though confidence on timing
is low. MVFR cigs may linger intermittently at times tonight but
will generally improve during the daytime hours tomorrow.

&&

.MARINE...
Issued at 330 PM EDT Thu Jul 16 2026

Dense Smoke Advisories remain in effect for all of Lake Superior and
northern Lake Michigan/Bay of Green Bay through Friday evening as
wildfire smoke from Ontario and MN continues to drift over the
region. Expect visibility to continue to fluctuate below 1 nm at
times. Will continue to evaluate whether these headlines need to be
extended in future forecast cycles, but there is potential for at
least some relief from the smoke heading into the weekend as a
system moves through the region Friday into early Saturday.
Otherwise, surface high pressure remains over Lake Superior through
tonight, keeping winds below 15 kts area wide. Winds may increase
near/above 20 kt at times Friday through the weekend as the
aforementioned system moves through, also bringing a potential for
thunderstorms.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Dense Smoke Advisory until 8 PM EDT /7 PM CDT/ this evening
     for LSZ162-240>251-263>267.

Lake Michigan...
  Dense Smoke Advisory until 8 PM EDT this evening for LMZ221-
     248-250.

&&

$$

DISCUSSION...CB
AVIATION...Thompson
MARINE...CB