Flat River, MO Weather

Key Messages

- Dry weather along with above normal temperatures are expected to continue through the week into this weekend.

Short Term

Issued at 226 PM CDT Tue Oct 20 2026

There's little change in the forecast this afternoon. An upper level ridge remains over the central CONUS sandwiched between troughs over both coasts. A sprawling surface ridge remains in control of the weather across the Great Lakes, Midwest, and Ohio Valley as well. The upper level omega block and surface ridge will remain in place through the short-term which will continue our stretch of uneventful weather. Temperatures across the forecast area are 3-5 degrees warmer today than yesterday, and it should continue to warm slowly tomorrow and Thursday due to good daytime insolation and light south to southeasterly flow.

Long Term

Issued at 226 PM CDT Tue Oct 20 2026

The omega block begins shifting east Thursday night, and the western trough moves over the Rockies by Friday evening. Medium range deterministic guidance shows the trough fracturing, and the resulting northern stream short wave moves across southern Canada and the northern Great Plains. The cold front attached to the surface reflection of the wave drifts through the Upper Midwest Saturday, and slows down to become nearly stationary across southern Minnesota, Michigan, and nothwest Iowa on Sunday. Models then show another upper level wave diving through southwest Canada Sunday night and into the northern Plains Monday where it phases with the left over southern stream energy. The combined positively tilted trough then digs southeast, which finally pushes the cold front through the Mid Mississippi Valley on Tuesday. All this adds up to continuing dry and warm weather for the Mid Mississippi Valley at least through the weekend south of the cold front, and probably for Monday and Tuesday as well. The LREF continues to show variance in the strength and position of the northern stream trough Friday/Saturday, and the combined trough Sunday through Tuesday. The variance mostly affects locations well north of our forecast area through the weekend. Temperature IQRs in the LREF are only 3-4 degrees in our area through Sunday. However, the IQR increases to 10 degrees across northeast Missouri and west central Illinois as the combined trough and cold front approach the area on Monday. The IQR spreads out to 10-15 degrees across the rest of the area on Tuesday as the members of the LREF attempt to push the front through. The deterministic NBM shows highs dropping from the mid and upper 70s on Sunday and Monday into the 60s Tuesday with the front. However, confidence in the forecast remains low early next week as guidance continues to have some issues with the placement of the front.

Aviation

Issued at 1000 PM CDT Tue Oct 20 2026

Mainly dry and VFR conditions are expected through the period with light winds.