Plymouth, IN Weather

Key Messages

- Areas of fog are possible in northwest Ohio and northeast Indiana this morning.

- Dry and pleasant weather persists through the week with highs generally in the 70s and lows around 50.

- The next chance of widespread rain does not arrive until Saturday night.

Discussion

Issued at 154 AM EDT Sun Oct 25 2026

Yet another day where fog is the only main forecast concern. This morning's fog forecast is more challenging than yesterday because winds have veered to a more southerly direction and we lost good Lake Erie contribution. Still, excellent radiational cooling conditions exist with the loss of any upper level clouds and some moisture appears to still be bleeding into northwest OH from the lake. Guidance continues to show a narrow swath of dense fog developing along the Maumee River with some observational evidence starting to support this idea. Confidence in widespread dense fog is much lower this morning and for now seems to be more of a localized, SPS-level event. Will continue to monitor obs closely through the morning and consider a dense fog advisory for the Fort Wayne to Wauseon corridor if necessary.

Lack of widespread fog and some light southerly flow/WAA today should push highs into the low 70s for most with some mid 70s possible in the far SW. Afternoon RH values drop to around 35 percent and dry fine fuels will continue to support some concern for small field fires (limited by very light winds). Winds veer even more for Monday morning and while some patchy fog may still be possible given light winds, not expecting any widespread/dense fog at this time, especially as crossover temps may be harder to exceed for Monday morning. A weak front washes out across our north on Monday and a brief return to cool NE flow arrives Tue morning. This will be another day to watch for possible fog development given ENE flow over the very warm lakes. Light S/SW flow returns Wed and Thu ahead of the next front and highs surge well into the 70s (possibly near 80 far SW). This front also washes out across our north as parent trough lifts into Quebec and ridge holds firm over the Ohio Valley. A few sprinkles are possible in our far NW on Thu but chances are low and impacts nil. SW flow quickly recharges heading into Halloween with highs well into the 70s and mainly dry conditions. Will have to watch the next decent system arriving Sat night into Sunday for more widespread rain chances. Still plenty of time for subtle changes but for now best chances for rain appear later Saturday night into Sunday.

Aviation

Issued at 635 AM EDT Sun Oct 25 2026

No significant changes are anticipated with the 12Z TAFs with main concern centered on first few hours of this valid period and fog potential. Hi-res guidance and observational trends support far northeast Indiana and northwest Ohio for fog formation this morning, with favored areas suggesting a bit of a terrain cool drainage effect. Low level winds have veered a bit over past 24 hours and influence from eastern Great Lakes is not as substantial today, and corresponding depth of moisture appears to be a bit more shallow. This should result in quicker mixing out of fog this morning, likely around or shortly after 14Z. KFWA still stands inline for best chance of IFR or even brief LIFR conditions with the fog through 14Z. Confidence remains lower at KSBN but will likely maintain TEMPO MVFR vsbys for an hour or two to begin the period. The rest of the period should feature VFR conditions and light southerly flow (5 knots or less) developing along western periphery of the anticyclone.

Iwx Watches

IN...None. OH...None. MI...None. MARINE...None.