


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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
706 FXUS63 KMQT 121948 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 348 PM EDT Sun Oct 12 2025 .KEY MESSAGES... - A round of showers presses west to east late tonight through Monday. Rainfall accumulations are expected to remain light, generally less than 0.25". - Temperatures will average slightly warmer than normal through Monday before becoming more seasonable. - There is a 40-70% chance for southerly wind gusts greater than 30 mph this afternoon into Monday morning, particularly for favored downsloping locations of the western and central high terrain and Lake Superior shorelines. - A period of southerly gales around 35 kts is expected over central Lake Superior late this afternoon into tonight. && .DISCUSSION... Issued at 347 PM EDT Sun Oct 12 2025 Afternoon RAP analysis and GOES water vapor imagery highlight upstream development as a vigorous trough over eastern Montana/western Dakotas supports a 986 mb low over southwest Manitoba. This is part of a broad mid level trough expanding the Canadian Prairie and the western CONUS. The ridge axes which once extended overhead is shifting southeast toward the Lower Great Lakes and surface ridging extending off a parent high over the St Lawrence Seaway is weakening. The trough and seasonably strong surface low over Manitoba lift northeast through tonight, strengthening the pressure gradient and southerly flow during this period. As a result, milder and breezier conditions are expected. Temps this afternoon in the upper 50s to mid 60s settle overnight into the upper 40s to mid 50s. Widespread winds of 5-15 mph, gusting to 25 mph are forecast. Wind gusts will be strongest in areas of south-southeast downslope flow where gusts will frequent into the 20-30 mph range. Probabilistic guidance aligns well with model soundings, highlighting potential for stronger winds this evening into early tonight. The EPS and NBM probabilities highlight between 40-70% chances for gusts between 35 - 40 mph accelerating off the north central and far western high terrain. The 12Z HREF guidance continues to portray much higher gust potential, which is often overdone in southerly warm air advection regimes. Utilizing it as support for higher gust potential and not an explicit wind gust forecast. Surface obs indicate a frontal boundary located near the west side of Minnesota. This is expected to progress toward the CWA, sending a round of light to occasionally moderate rain showers from west to east across the UP tonight through Monday. Guidance continues to favor accumulations between a few hundreths to 0.25", with a 20-40% chance for higher amounts; best chances reside in the Keweenaw. Temps on Monday over the far west will struggle to get out of the 50s already being in the wake of the cold front. Elsewhere, temps look to reach into the low to mid 60s prior to frontal passage. Breezy west winds continue behind the front in the Keweenaw with gusts likely between 20-30 mph. Light northwest winds continue overnight into Tuesday as dry weather returns and temps settle into the mid 30s to mid 40s. High pressure moving in for the middle portion of the week leaves dry, quiet, and more seasonable weather likely through at least Wednesday night. A ridge riding shortwave Tuesday night may try to scrape some light showers along the south, but the current forecast favors antecedent dry air limiting PoPs. PoPs return on Thursday, continuing through next weekend as this high pressure weakens and quickly departs to the east. At the same time, the mid level ridge that had built up over the Midwest breaks down, shifting a troughing pattern over the region for the weekend. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 133 PM EDT Sun Oct 12 2025 This afternoon low clouds continued to erode over the central and east with MVFR conditions reported at SAW. Expecting these clouds to become sct/few shortly so did not include MVFR at the start of the TAF. Southerly winds will be gusty at the TAF sites through late tonight, shifting westerly Monday morning. A strong low level jet will result in a period of LLWS tonight at all the TAF sites. Showers will accompany a front pushing across the U.P late tonight with MVFR CIGs expected to develop behind the front Monday morning. && .MARINE... Issued at 347 PM EDT Sun Oct 12 2025 Southeast winds ramp up this afternoon as a strong low pressure system lifts northeast from Manitoba to Hudson Bay tonight through Monday. The resulting pressure gradient draped across the Great Lakes will enable gusty southerly winds upwards of 30-35 kts, mainly north and east of the Keweenaw where guidance suggests 50-70% chance for Gales to 35 kts this evening into early Monday morning. Winds veer west behind a frontal boundary on Monday, gradually settling to 15-25 kts by the end of the day. Winds settle to around 20 kts or less on Tuesday, save for some stray guts up to 25 kts over the southeastern waters, as high pressure builds in. Winds settle below 15 kts across the lake Tuesday night, holding through Thursday morning. High pressure quickly gives way on Thursday, reintroducing 20-30 kt winds to the lake for next weekend. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Gale Warning until 8 AM EDT Monday for LSZ244-245-264>266. Lake Michigan... None. && $$ DISCUSSION...77 AVIATION...NL MARINE...77