709
FXUS63 KMQT 130750
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
350 AM EDT Sun Jul 13 2025

.KEY MESSAGES...

- Wildfire smoke from Canada will be over the area through at least
tonight resulting in air quality concerns and reduced visibility.

- This evening, a few showers and thunderstorms may arrive in the
western UP. A few of these storms may be strong to severe, with a
Marginal Risk (category 1 of 5) for damaging winds and 1+" hail.

- Periods of showers and thunderstorms possible Tuesday into
Wednesday (30-60%).

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 344 AM EDT Sun Jul 13 2025

Upper air pattern (per RAP analysis) consists of a negatively tilted
trough (cut off at and below 700mb) over northern Ontario with a
minor embedded shortwave extending southwest from the trough over
the Plains. With minor ridging and height rises over the UP in the
wake of the main trough`s passage yesterday, subsidence has kept
wildfire smoke from upstream fires in northwest Ontario and Manitoba
near the surface over the UP, with many UP METARs showing visibility
sub-6 miles this evening and PurpleAir sensors showing PM2.5 AQI of
150-215+. Even if those sensors are biased high by a category, the
air quality is poor enough that people in sensitive groups may
experience some health issues, especially those with poor air
filtration or those that cannot prevent smoke from getting inside
their homes. RAP-Smoke and HRRR-Smoke show little improvement
throughout the morning and even show increasing concentration of
near-surface smoke in the western UP this afternoon. Anyone with air
quality concerns should refer to the Air Quality Alert in effect for
more information including links to health information and best
practices. Despite the smoke, high temperatures today will still be
around the 80 degree mark with otherwise sunny skies expected.

Attention then turns upstream as the aforementioned minor Plains
shortwave approaches, forcing isolated convection upstream.
Increasing flow aloft will provide better shear environments than
much of the recent convective setups with the HREF showing mean 0-
6km shear values of around 30 kt and increasingly sickle-shaped
hodographs in the lower levels allows 0-3km SRH values to climb to
the 100-200 range. There is a question of available instability as
the timing of when showers/storms would arrive would be around 0Z-
6Z, after the peak of diurnal heating, so HREF mean SBCAPE is only
around 750 J/kg, but there is considerable spread in the minimum and
maximum modeled values (especially given that smoke could dampen the
ability for the surface layer to destabilize). Additionally, the
surface trough will be weakening as it approaches the UP, so forcing
will be weakening. Available moisture will not be an issue though as
much of the short range guidance has dew points in the 60s in the
west ahead of this activity. To recap: good shear, weakening lift,
questionable instability, and good moisture. All of this
combines for a conditionally marginal severe setup, as if
convection does have enough forcing and instability over the
region, the shear and moisture will support some isolated
supercells capable of severe wind and hail. However, given the
failure of better forced and more unstable events this summer,
confidence in storms even lasting to reach the UP is not
particularly high, with PoPs only up to 35 percent. Even with
storms petering out after 06Z, the boundary will help mix out
some of the wildfire smoke, bringing some (at least brief)
relief to the hazy skies. Expect low temperatures to fall to the
low 60s tonight.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 249 PM EDT Sat Jul 12 2025

A few showers or perhaps a thunderstorm will be possible Sunday
night as a weakening boundary tries to move through from the west.
For early next week, zonal midlevel flow initially will become
more amplified with time over the northern tier of the CONUS as
troughing digs into the northern Plains, resulting in SW flow
over the local area. At the surface, an area of low pressure
will develop over the Rockies/central Plains, with a warm front
extending NE into the northern Plains or upper Great Lakes.
After a dry and seasonably warm day Monday (highs mainly in the
80s), precipitation chances enter the picture again
Tuesday/Wednesday as impulses in the SW flow team up with
diurnal instability to generate areas of showers and
thunderstorms. There is still uncertainty with timing and
placement of the front upon which most of the activity should be
focused, so general broad-brush chance to low-likely (30-60%)
PoPs will suffice, with Wednesday having relatively higher
probabilities for precipitation over most areas. With relatively
more ensemble members having the front north of our area on
Tuesday, another warm day in the 80s looks likely, with a cool-
down becoming more likely Wednesday on the back side of the
front. Gradually trending drier and seasonably cool for the end
of the week as high pressure builds over the northern
Plains/Great Lakes.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 144 AM EDT Sun Jul 13 2025

Primarily VFR cigs are expected during the 6Z TAF period, but
Canadian wildfire smoke will continue to yield varying levels of vis
restrictions most of the period. Mainly MVFR vis is anticipated;
this morning/early afternoon is expected to be the worst period
where some IFR may mix in before some gradually improvement is
anticipated into this evening/tonight, possibly to VFR at all sites.
That said, the improvement tonight likely won`t last long as another
batch of wildfire smoke looks to arrive from the NW for Mon. Exact
timing of vis restrictions remains a low confidence point of the
forecast as model near-sfc smoke does not necessarily correlate to
sfc vis. Also FU/HZ particulates may impact FG/BR late tonight...
not captured well by model guidance but chances remain low (~25% or
less). Will continue to monitor and update TAFs with trends and
observations.

Otherwise, W to SW winds will hold around 10 kts with gusts up to 20-
25 kts at CMX. Elsewhere W to SW winds settle to around 5-8kts
through early this morning, increasing to around 10 kts by this
afternoon. Some gusts at IWD may push near 20 kts in the afternoon.

&&

.MARINE...
Issued at 249 PM EDT Sat Jul 12 2025

A weak boundary will bring a chance of thunderstorms mainly over the
eastern half through this evening. Behind this line, visibility will
likely be reduced in areas of fog and wildfire smoke into Sunday.
Winds will increase tonight into Sunday with west-southwesterly
gusts to 20-25 kt through Sunday, mainly over the western half.
Winds diminish early in the week, but could increase to near 20 kt
from the north late in the week behind a frontal boundary. Unsettled
weather returns Tuesday/Wednesday with additional rounds of showers
and thunderstorms possible, plus the potential for fog where
rainfall occurs.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Air Quality Alert until noon EDT /11 AM CDT/ Monday for
     MIZ001>007-009>014-084-085.

Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...GS
LONG TERM...Thompson
AVIATION...Jablonski
MARINE...Thompson