060
FXUS63 KMQT 151830
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
230 PM EDT Sun Jun 15 2025

.KEY MESSAGES...

- Strong or severe storms are possible (5-15% chance) Monday
  afternoon/evening across the west half of Upper Michigan.
  Damaging winds and large hail are the primary risks.

- Greatest chances for rain and thunderstorms Tuesday night
  through Wednesday night are south and east. Scattered
  showers/storms possible Thursday across Upper Michigan.

- Near normal temperatures this week trend above normal by late
  this coming weekend.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 230 PM EDT Sun Jun 15 2025

Overcast skies have blanketed the southern and western portions of
Upper Michigan today, while the east, north-central and Keweenaw
have entertained partly to mostly clear skies. In response, the
warmest temperatures have been observed there, with upper 60s to mid
70s being reached so far. Where cloud cover has been more
persistent, sites have only warmed into the upper 50s to mid 60s.
High pressure extending into the region from the northeast has
supported mostly light winds and a lake breeze is noted stretching
across Marquette County eastward on KMQT and CASMR. For the rest of
the afternoon, skies should continue clearing, while the interior
west likely stays under mostly cloudy conditions. This will promote
additional warming, with more sites climbing into the upper 60s to
low 70s, whereas the interior west will likely only climb into the
low to mid 60s.

Tonight, while zonal flow and high pressure continue to keep our
forecast area dry, upstream a vigorous shortwave will press eastward
across the Dakotas while a cold front descends south from Canada.
Surface low developing along the front in eastern North
Dakota/western Minnesota will press into the Great Lakes Monday
evening, dragging behind its cold front. Overnight Monday, this
front will slowly press into the forecast area while the surface low
lifts into Ontario. Ahead of the front on Monday, upstream
convection will press eastward into our forecast area, with various
deterministic packages suggesting these clusters could move into an
environment favorable for continued convection and strong/severe
thunderstorms. This environment, MUCAPE growing 1500-2500 j/kg
alongside deep layer 0-6km bulk shear increasing to near 30kts, is
mainly focused across western Upper Michigan by afternoon. CAMS
present little concensus in the way of timing or position of these
features, and some even suggest weak, pre-frontal showers developing
Monday. Much will depend on upstream convection/MCS development and
how well we destabilize, as well as how well things maintain
themselves as the front moves into the region. At the very least,
greatest probability of showers and thunderstorms is the west half
by late afternoon/evening, then shifts eastward as the night
progresses.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 230 PM EDT Sun Jun 15 2025

Weak, quasi-zonal flow Monday breaks down with the passage of Monday
night`s shortwave, resulting in weak ridging on both ends of the
country and troughing across the Central Plains Tuesday. Various
shortwaves are noted within this broad area of troughing as it
slowly migrates eastward into and through the Great Lakes region to
round out the end of the coming work week. Upper level ridging
builds into the Central Plains Friday, which stretches into the
Upper Great Lakes Friday night. This ridge looks to gradually result
in an amplified trough/ridge pattern across CONUS through the
weekend. This evolution provides almost daily chances of rain or
thunderstorms for our forecast area this week and coming weekend.

Beginning Tuesday, surface low and associated cold front tied to
Monday evening`s thunderstorm chances will continue to press
northeast and east/southeast respectively, resulting in the slow end
to precip across our forecast area through the day. How slowly looks
dependent on how far the cold front makes it Monday night. A broad
look at various CAMs suggests the front should make it into the west
by early Tuesday morning, then exit to our east by early evening.
Precip should follow this same pattern, with precip ending in the
west by early afternoon and the east by early evening. Instability
ahead of the front across the central and eastern third of the
forecast area may be enough for some thunderstorms, but severe
weather is not expected. Highs across the region span the 70s and
low 80s, with the coolest conditions expected near Lake Superior.
Dry conditions follow Tuesday night for most, although a stray
shower or two can`t be completely ruled out, mainly central and
east. Overnight lows dip into the 50s to low 60s south-central.

While the cold front presses eastward through the Great Lakes and
midwest thereafter, multiple shortwaves within the eastward
migrating trough will help to support various waves of precip along
the boundary through Thursday night. For us, the best chances for
showers or thunderstorms associated with these features will be the
central and eastern portions of the forecast area. Similarly to
Tuesday, severe weather isn`t expected. Thursday afternoon and
evening, daytime instability along with the last wave within the
trough looks to swing through the Great Lakes. This may support more
widespread showers and thunderstorms before conditions diminish with
the setting sun. Daytime highs are expected to climb mostly into the
70s or low 80s while overnight lows settle into the high 40s to 50s.

Friday and into the weekend, ridging presses into our forecast area.
Guidance suggests another wave of showers/storms Friday
night/Saturday. On Sunday, board area of low pressure across the
Northern Plains may result in a warm front lifting through the
region and widespread mid to upper 80s for daytime temperatures.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 121 PM EDT Sun Jun 15 2025

Slowly eroding cloud cover will support VFR conditions this
afternoon and evening at KCMX/KSAW under light winds. Abundant low
level moisture at KIWD though will maintain MVFR ceilings at least
into the overnight hours. Guidance suggests improvement to VFR after
midnight. A cold front will press into the region late Monday, with
increasing moisture and some forcing for shower activity by Monday
morning ahead of the boundary. Expecting MVFR ceilings to develop at
KCMX/KIWD with scattered showers that could move over all terminals.

&&

.MARINE...
Issued at 243 PM EDT Sat Jun 14 2025

Aside from some northeasterly winds funneling into the western arm
of the lake through this evening, winds should be fairly weak at
less than 20 kt for the rest of the weekend into the upcoming week.
Stronger winds cannot be ruled out in and around thunderstorm
episodes which will become possible Monday into Tuesday (30-40%
chance). Areas of fog will be possible early next week as moisture
increases over the cold lakes, especially where it rains.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...JTP
LONG TERM...JTP
AVIATION...JTP
MARINE...Thompson