852 FXUS63 KAPX 231021 AFDAPXArea Forecast Discussion National Weather Service Gaylord MI 621 AM EDT Tue Sep 23 2025
.KEY MESSAGES...
- Scattered showers and isolated thunderstorms this afternoon.
- Areas of dense fog are possible again tonight.
- Shower chances remain into mid week.
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.SHORT TERM /THROUGH TONIGHT/... Issued at 201 AM EDT Tue Sep 23 2025
Pattern Synopsis and Forecast:
Slow meandering upper low will continue to plague the region with shower chances today. The center slightly drifts/retrogrades to the south and southwest today and tonight, with the upper low position moving from approximately just north of the SOO to the ~Straits or so tonight. Lift from this feature will result in showers and a few storms through the period, especially this afternoon and evening. Winds shifted or will shift to the northwest today denoting a subtle boundary passage which will shunt some moisture/instability to the southeast to some extent.
Primary Forecast Concerns:
Showers/thunderstorms:
Slow meandering upper low continues to plague the region with shower and storm chances today. Latest 00Z guidance has come into decent agreement on a decisive boundary that has moved or will move through the region early today with less sfc moisture and thus much less instability during the daytime hours today. As a result, strong thunderstorm potential seems quite low this afternoon. Best locations for showers and storms will be close to the upper low center and across southeast portions of the county warning area. Thus these locations will feature the highest POPs and thunderstorm chances, although some of the latest guidance really keeps the rain chances quite low today so we`ll see. An isolated stronger storm cannot be ruled out, although the current progged thermodynamic environment looks less impressive than previously thought and looking increasingly unlikely. Locally heavy downpours will be the primary concern with the strongest storm(s), cannot completely rule out an isolated instance of gusty storm or small hail as well.
Fog development:
Another round of fog is anticipated later tonight as temperatures cool to saturation and moisture returns inland off Lake Huron. Certainly is supported when looking at the HREF/NBM statistical/probability guidance, in addition to deterministic HRRR visibility, which suggests the potential for at least patchy areas of significant visibility reduction, especially across interior locales.
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.LONG TERM /WEDNESDAY THROUGH MONDAY/... Issued at 201 AM EDT Tue Sep 23 2025
Day 2-3 (Wednesday - Thursday):
Upper low continues to linger across the region during the mid week time frame with modest moisture and weak instability. Consequently, the isolated to scattered shower and isolated storm threat will remain during the Wednesday - Thursday time frame. Subtleties/energies within the upper low circulation, and the position of the upper low in general, will determine slight upticks in shower potential which will be monitored in the coming days. A few downpours will be the main concern with activity during this time frame.
Days 4-7 (Friday - Monday):
Upper low finally washes out to the east late week and into the weekend as sfc low pressure system tracks across the interior northeast. Troughing passes well to the north across Ontario this weekend, with generally drier conditions overall during this time frame. This system may draw in a touch cooler temperatures, at least briefly and relatively, toward the end of the weekend into early next week. Otherwise, temperatures through the entirety of the forecast area remain near to several degrees above late September normals.
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.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/... Issued at 617 AM EDT Tue Sep 23 2025
Widespread MVFR to LIFR producing fog/mist/stratus expected to gradually mix out this morning...likely leaving a mix of MVFR to VFR cigs this afternoon. Likely looking at another round of significant fog/mist/stratus development by later this evening through the overnight. A few more showers and thunderstorms expected today, but confidence remains very low both with regards to timing and overall coverage of these showers. Light winds through the period.
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.APX WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None.
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SHORT TERM...JLD LONG TERM...JLD AVIATION...MSB
NWS APX Office Area Forecast Discussion