753
FXUS63 KMQT 261959
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
359 PM EDT Sat Apr 26 2025

.KEY MESSAGES...

- Patchy fog over the interior east and south central is
  possible tonight.

- Rain and snowmelt will continue to lead to rises on area
  rivers and possible minor flooding on typically flood-prone
  rivers, especially early to mid next week during and after a
  strong low pressure brings additional rainfall to the area.

- An active and warmer pattern is expected for early next week.
  Some strong to severe thunderstorms are possible (30%
  chance), with severe hail being the primary threat; severe
  winds are a less likely secondary threat.

- There is a non-zero chance for flash flooding across our area
  Monday into Tuesday morning, with the highest chance of
  occurrence currently over the west (5% according to WPC).

- North to northwest gales of 35 knots possible Tuesday over at
  least the north central and eastern Lake Superior.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 247 PM EDT Sat Apr 26 2025

As ridging moves in, expect pleasant and calm weather the rest of
today. With weakening northerly flow occurring this afternoon,
expect the Lake Superior marine layer to keep highs in the 40s along
the shoreline, the north central, and the northern half of the east;
with the light winds going, it may feel a little chilly from time to
time. However, outside of the influence of the Lake Superior marine
layer, high temperatures are projected to stretch into the 50s. In
addition, we could see RHs drop down as low as the mid 20s in the
interior west this afternoon as the cool and moist marine layer
fails to reach this area. However, given the light northerly winds,
the recent rainfall and snowmelt, and fairly cool temperatures
today, the fire weather danger over the west is fairly limited this
afternoon.

Clouds build into the western U.P. tonight as a low pressure
develops over the Northern Plains and lifts towards Lake Superior.
As the warm front of the low begins to develop just west of us
tonight, expect the surface winds to become southerly, keeping the
western U.P. warmer during the late night to early Sunday morning
hours. However, expect the winds over the eastern U.P. to be very
light to calm tonight; thus, in addition to the clear skies, we
could see temperatures bomb-down over the interior east. Therefore,
thinking lows tonight over the western U.P. will be limited to the
mid 30s to around 40 along the Lake Superior shoreline, whereas the
eastern U.P. could see temperatures in the mid 20s or lower in the
interior areas. With the temperatures bombing-down so low in the
interior east, we could see some patchy FG develop over this area
and the south central late tonight before eroding away Sunday
morning with the sunrise.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 324 PM EDT Sat Apr 26 2025

Active weather starts out early next week as a low pressure lifting
from the Northern Plains approaches Lake Superior throughout the
day. As the warm front of the low begins to crawl towards us on
Sunday and Sunday evening, we could see some light rain showers
develop over the western half of U.P. by the afternoon. However,
with the better forcing being focused further west, I`m thinking the
convection will die out as it travels eastwards. While moisture is
advected into the area, some antecedent dry air at the sfc on Sunday
could help RHs bottom out to around to just below 30% over the far
interior east by the afternoon (this area will also be sunnier).
Besides this, expect winds from the south and clouds to increase
Sunday and Sunday night across the area.

The main event comes later on Monday as the low moves into Minnesota
and approaches western Lake Superior. Given that we will be solidly
under the warm sector of the low, elevated convection could begin
moving into the area as soon as Monday afternoon over the west. With
a LLJ providing ample shear and the warm, moist air from the Gulf
providing ample energy aloft, severe hail is the expected threat
Monday afternoon through Monday night ahead of the low`s cold front
as the tilting of the updrafts with height in the mid to upper
levels will provide enough ingredients for mesocyclones to continue
once they get started. With model guidance hinting at some drier air
being entrained in the mid to upper levels of the atmosphere, we
could also see severe winds reach the sfc too, provided that the
downdrafts can penetrate the inversion caused by the warm front in
the lower levels. Given that confidence has increased on the track
and timing of the low, the SPC has increased our chance for severe
weather up to 30% over the western U.P., whereas a 15% chance or
more remains over the eastern half (the eastern half will likely
remain storm-free until the overnight hours). Therefore, keep your
eyes on the forecast for Monday and Monday night, as severe hail
(greatest chance) and severe winds (lower chance) could occur.
Thankfully, with the convection being elevated in nature, no
tornadoes are expected.

As the low moves through Lake Superior Monday night, the cold front
begins pushing into the region early Tuesday morning. We could see
an uptick in severe weather activity at the triple-point of the low,
as discrete supercells ahead of the cold front potentially give way
to a line of convection along the frontal boundary. Should this
linear feature form, this may elevate severe weather potential as
the frontal boundary will have a vigorous thermal boundary and
impressive height rises of 5+ mb/3 hr (wow!) behind it. In addition,
with ensemble guidance showing PWATs increasing to over 1" to
potentially 1.25" ahead of the cold front (which is around the 95th
percentile of modeled climatology), should training of storms occur,
we may see some flash flooding across the area, particularly in the
inundated areas in the northern tier that have not been snow-free
for all that long. As of this writing, WPC has kept us in at least a
5% chance for flash flooding over the western half of the U.P.,
where greater liquid amounts are currently projected to fall. As the
cold front passes through, we could see one more burst of moderate
to potentially heavy rainfall push through before precipitation
ends. In addition, we may see a transition over to snowfall over the
northern tier early Tuesday morning as the precipitation is ending.
However, given that surface temperatures are still expected to be
above freezing, no snowfall accumulations are expected. The last of
the precipitation ends by late in the afternoon.

Behind the active weather early next week, expect calmer conditions
on Wednesday as a high pressure ridge rolls through the region.
However, more active weather could be on the way, as a weak low from
Canada phases with a low lifting through the Lower Midwest late next
week. This could bring additional rain showers and cooler than
normal high temperatures back across the area. As the phased low
continues to lift away into northern Quebec, a rex block over the
Plains looks to travel eastward across our area for next weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1247 PM EDT Sat Apr 26 2025

High pressure ridging today into tonight will keep conditions
generally VFR across the area throughout the TAF period. There is a
30% chance or less of seeing some FG over SAW tonight as the winds
calm down overnight, but there is still quite a bit of uncertainty
at this time on whether the temperatures will cool down enough to
reach the dewpoint and cause cloud condensation at the sfc. We could
see the first wave of rain showers move over IWD early Sunday
afternoon as a low pressure develops over the Northern Plains and
lifts towards Lake Superior.

&&

.MARINE...
Issued at 358 PM EDT Sat Apr 26 2025

Light winds of generally 20 knots or less this afternoon continue
through tonight and Sunday as high pressure moves through the
region. As a low develops over the Northern Plains and then lifts
towards Lake Superior early next week, expect southerly winds of 20
to 30 knots to develop over the eastern half of Lake Superior ahead
of it on Monday, with a few gale force gusts up to 35 knots being
possible along the southern nearshores by Munising (LREF shows over
an 80% chance). Within the warm sector of the low Monday afternoon
through Monday night, expect some rain showers and thunderstorms,
with some of the thunderstorms potentially bringing severe hail
(greater chance) and severe winds (lower chance) to the water.
Currently, the SPC shows a 30% chance for severe weather over the
western half and a 15% chance for severe weather over the eastern
half, with the eastern half not seeing convection most likely until
Monday evening. The low moves through west and northern Lake
Superior Monday night before its cold front pushes through early
Tuesday morning. Behind the cold front, expect north to
northwesterly gales of 35 to potentially even 40 knots over at least
the north central and eastern lake on Tuesday (60 to 90% chance
according to the LREF). Thus, a Gale Watch has been issued for these
areas of the lake. With high pressure quickly building in behind the
front, expect winds to go down to 20 knots or less again as soon as
Tuesday evening. The light winds are projected to continue through
the rest of next week.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Gale Watch from Tuesday morning through Tuesday afternoon for
     LSZ243-244-263-264-266.

Lake Michigan...
None.

&&

$$

SHORT TERM...TAP
LONG TERM...TAP
AVIATION...TAP
MARINE...TAP