Area Forecast Discussion
Issued by NWS Marquette, MI

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
127
FXUS63 KMQT 091137
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
737 AM EDT Thu Oct 9 2025

.KEY MESSAGES...

- Widespread light to moderate rain expected Thursday night and Friday.

&&

.DISCUSSION...
Issued at 249 AM EDT Thu Oct 9 2025

Mostly clear skies under high pressure has allowed for light winds
and effective radiational cooling. As of this writing, most
observation sites have fallen into the 30s, with a smattering of 20s
across interior eastern Upper Michigan. A few warmer spots are noted
as well, mainly in the Keweenaw. Additional cooling during the rest
of the overnight period is expected as the surface high continues to
settle eastward into Ontario. Still on track for widespread upper
20s by sunrise for most interior locations and 30s elsewhere.

Mid-level ridge currently stretching north through the Plains will
migrate east today, bringing the ridge axis through the forecast
area by afternoon as a shortwave dives southeast through middle
Canada. With the surface high to our east and a tightening pressure
gradient associated with the shortwave and attendant cold front
moving through the northern Plains/middle Canada, slight warm air
advection will enable daytime temperatures to climb into the upper
50s east to the low to mid 60s west. Skies are expected to remain
mostly clear for a majority of today, but increasing clouds in the
west is expected this evening as the front approaches the region.
Tonight, continued southerly to southwesterly flow will likely
continue the day`s 15-20 mph gusts near Lake Superior into the
overnight period, perhaps to 25-30 mph at times, while temperatures
fall mostly into the 40s. Rain is also expected to press into Upper
Michigan from west to east tonight, becoming more widespread Friday
morning as a surface low develops along the cold front. In the past
24 hours, the trend has been toward developing this low a little
further west, now just northwest of Thunder Bay, and a slower
transit through the Upper Great Lakes. In terms of sensible weather,
this change means a dry slot may support a break in rainfall Friday
for the west half before a secondary push of rain wrapping around
the low moves into the forecast area in the afternoon and evening.
Temperatures are likely to peak in the mid to upper 50s Friday.

Rain will taper Friday night into early Saturday, followed by dry
conditions Saturday afternoon into Sunday. A slight warming trend is
noted between the two days thanks to the next system moving closer
to the region Sunday. Daytime highs Saturday look to peak near 60F
and then widespread mid 60s Sunday. Broad troughing begins to
establish itself across the Northern Rockies and the initial wave
lifting northeast from the base results in a surface low lifting
from the Dakotas into Manitoba Sunday. A warm front associated with
this system presses into the Upper Great Lakes Sunday night followed
by its cold front Monday. Rain looks to move into the region thanks
to these features Sunday evening then gradually taper through the
day Monday. Another high looks to build across the region afterwards
through the middle of next week before the next low lifts out of the
Central Plains.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 735 AM EDT Thu Oct 9 2025

VFR conditions will prevail for the duration of the TAF period.
Winds will be light through the day before becoming gusty tonight as
low pressure drops south into the area. Increasing low level winds
will bring a period of LLWS at IWD tonight. Showers will also
overspread that area but conditions looks to remain VFR. After the
TAF period MVFR or possibly IFR conditions could develop due to low
clouds and showers associated with the low pressure moving south
through the area.

&&

.MARINE...
Issued at 249 AM EDT Thu Oct 9 2025

Light southerly flow prevails today, but increases tonight ahead of
a cold front moving into the Upper Great Lakes. By Friday morning, a
surface low will develop along the cold front. In the past 24 hours,
the trend has been toward developing this low a little further west,
now just northwest of Thunder Bay, and a slower transit through the
Upper Great Lakes Friday into Friday night. This progression doesn`t
change the forecast much, but does lend confidence to the widespread
potential 30kt winds ahead of and behind the system. Gale potential
still exists, and latest EC ensemble system continues to suggest ~30-
50% chances, but this is an outlier and notably higher then
suggested by other guidance packages. It should also be noted that
the deterministic EC has increased winds for the northwest flow on
the tail end of the system to low end gales. For now, will hold off
on a gale watch/warning since confidence still isn`t high enough,
but should the upward trend continue, a warning may be needed for
late tonight into Friday afternoon.

Behind the system, northeast flow gradually lightens Friday night as
it becomes more easterly. Expecting winds below 20kts Saturday.
Increasing pressure gradient is expected late Saturday night into
Sunday as the next system organizes in the Northern Plains. An
upward tick has been observed in guidance, now suggesting that a low
end southeasterly/southerly gale looks good with this system late
Sunday/Monday. Winds become northwesterlies behind the system`s cold
front Monday night/Tuesday and slowly fall below 20kts by Tuesday
night.

&&

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

&&

$$

DISCUSSION...JTP
AVIATION...NL
MARINE...JTP