Dead River Storage Basin Michigan Weather Forecast Discussion

644
FXUS63 KMQT 151928 CCA
AFDMQT
Area Forecast Discussion...CORRECTED
National Weather Service Marquette MI
328 PM EDT Wed Oct 15 2025
.KEY MESSAGES...
- Seasonable temperatures for midweek followed by a warm start to
the weekend.
- Rain chances increase late Thursday and continue into the weekend.
&&
.DISCUSSION...
Issued at 325 PM EDT Wed Oct 15 2025
This afternoon model analysis and satellite imagery showed an upper
level low pressure over the southwestern U.S with ridging through
the northern Plains. Radar data showed showers moving through the
U.P during the morning hours bud dry air in the low levels limited
much of the precip from reaching the ground, especially over the
northern half of the U.P. Widespread cloud cover this morning had
given way to clearing skies this afternoon. Temperatures were
seasonable, mainly in the 50s.
The upper level low pressure over the southwestern U.S will lift to
the northeast through Thursday and deepen, with a surface low
deepening over eastern MT and the North Dakotas as it moves out of
the Rockies. This low will track into Ontario through Saturday
before occluding and retrograding around the west side of the Hudson
bay on Sunday. Showers will be possible at times through Saturday as
a preceding warm front moves through the area Thursday night and a
cold front arrives on Saturday as the low pressure tracks north of
the area.
For tonight expect clear skies over much of the U.P and light winds
which should result in decent radiational cooling. Dropped
temperatures a few degrees below the NBM guidance with lows in the
low 30s over much of the interior. Patchy fog may form over parts of
the central and eastern U.P.
Clouds will increase from west to east Thursday as the warm front
approaches the area. Showers will also accompany the front, moving
into the western U.P Thursday afternoon and overspreading the rest
of the U.P Thursday evening.
For Friday the area will be in the warm sector, between the cold
front and the warm front, resulting in increasing dewpoints and
temperatures warming into the low 70s west to the mid 60s east. A
few showers will still be possible early in the day over the east
and late in the day over the west.
Showers and a few thunderstorms are expected over the central and
eastern U.P on Saturday as a cold front pushes into the area and
stalls out with the surface front weakening but still evident at 850
mb. Temperatures will warm into the 60s on Saturday afternoon.
There is quite a bit of uncertainty for Sunday into early next week.
Deterministic models show a low pressure developing along the
stalled frontal boundary as the western trough shifts east with the
surface low tracking through the Great Lakes. The exact track of the
low varies significantly among the guidance. 500mb height anomalies
in the cluster analysis are fairly evenly grouped with all four
clusters showing negative height anomalies over the Great Lakes, two
of the clusters would have the upper level low moving through the
southern Great Lakes and the other two through the northern Great
Lakes. The more northerly solutions favor widespread rainfall over
the U.P, especially central and east while the more southern track
would keep much of the rainfall south and east of the area. The NBM
has been trended up some with the PoPs in the east for Sunday and
through midweek as cool northwest flow should at least promote lake
effect rain showers. Kept with the NBM guidance at this time and
hopefully models will come into better agreement over the next few
cycles.
&&
.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 131 PM EDT Wed Oct 15 2025
Good flying conditions for most of the TAF period. The only
exception could be a period of MVFR conditions at IWD tomorrow as a
warm front brings rain showers to Upper Michigan. Will also have
to continue to monitor for any of those conditions reaching CMX
and SAW. Meanwhile, winds will be light and variable and non-
impactful.
&&
.MARINE...
Issued at 325 PM EDT Wed Oct 15 2025
Expect light winds over the lake tonight through Thursday. Southerly
flow develops on Thursday night into Friday as a low pressure tracks
through Ontario. Winds of 25 to 30 kts look likely on Friday, with
the NBM having a 60-80% chance of exceeding 30 kts. The NBM guidance
is showing a period of gales 35-40kt over the eastern lake on Friday,
especially in the evening. At this point kept with the NBM guidance
but given the stable flow over the lake it is possibly that the NBM
is overdoing the winds (this may be a marginal gale event). Another
period of gales will be possible on Sunday as a low pressure tracks
through the Great Lakes. There is still uncertainty in the track and
strength of the low and thus the magnitude of the winds Sunday.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
DISCUSSION...NL
AVIATION...TDUD
MARINE...NL

NWS MQT Office Area Forecast Discussion