Mendon, MI Weather

Key messages

- Warm and dry today with highs in the mid 70s.

- Very light rain is possible on Thursday followed by slightly cooler temperatures.

- More rain is possible over the weekend with the best chances on Sunday but forecast confidence for this period remains low.

Discussion

Issued at 226 AM EDT Wed Oct 28 2026

Another warm and tranquil day as ridge rebuilds behind departing shortwave responsible for current mid/high clouds and virga. These clouds will scatter during the day and highs climb into the mid 70s for most given some light SW flow/WAA. Mild overnight lows expected given increasing SW gradient and clouds ahead of the next cold front. Only mid 50s expected in our NW zones. As previously mentioned, this cold front will feature a moderate prefrontal theta-e surge (thanks to a 30-40 kt LLJ) capable of finally moistening very dry/stable airmass that has been in place for quite some time. However, better mid and upper level dynamics remain displaced well to our north. Decent 1000-850mb convergence within a moderate theta-e ridge will be enough to spark a narrow line of light showers on Thu but total rain amounts will be very light (a few hundredths at best). The best chances will be in our northwest where better moisture and forcing reside. Areas south of US-24 likely remain dry. No thunderstorms expected given virtually no instability so overall no impacts anticipated. Postfrontal airmass is cooler but not particularly cold given it is almost Halloween. Lows Thu night dip near 40F with highs on Fri in the 60s (still above normal).

Forecast details for the weekend and early next week remain uncertain. A subtropical Pacific jet streak/shortwave lifts into the region in piecemeal fashion over the weekend followed by the eastward ejection (in some fashion) of a Pacific Northwest upper low. This is a convoluted mid/upper level pattern evolution that models are still struggling with immensely. The initial shortwave and theta-e surge could bring some light rain to our W/NW counties early Sat but CVA and moisture advection are both very meager. Any rain will be light and it could easily remain entirely dry. These low chance PoP's extend into the early evening. Some light sprinkles can't be entirely ruled out for Sat evening activities but overall impacts should be minimal. Better rain chances arrive on Sun but even this is no slam dunk. Several guidance sources suggest the main trough and better moisture pass just to our S/SE. Attention then turns to large upper low migrating across the country. Models continue to show an incredibly high degree of spread with how this upper low evolves. Expect we will get some more widespread/moderate rain out of it at some point but timing is very up in the air.

Aviation

Issued at 130 AM EDT Wed Oct 28 2026

Midlevel shortwave supporting widespread 12 kft ceilings this morning but low levels remain very dry and VFR conditions will persist. Latest guidance shows a much lower chance for fog development. High clouds briefly scatter later today but return early Thursday morning as a weak cold front approaches the region. No aviation impact anticipated.

Watches, warnings and advisories

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