textproduct: Des Moines

KEY MESSAGES

- A cold front will pass through the area into Wednesday morning. Breezy winds out of the northwest are expected behind the front on Wednesday with gusts up to 25 mph.

- Outside of a rouge sprinkle north/northeast this afternoon or south tonight, dry conditions are expected through the end of the week. Patchy fog is possible overnight.

- Shower/storm chances return late Friday night into Saturday morning with additional chances later in the weekend and into early next week.

- Temperatures in the 80s through the work week with a slight warm up Friday and then warming further into the weekend with heat indices in the 90s on Sunday.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 231 PM CDT Tue Aug 25 2026

Upper pattern features a high over the southwest U.S. and a trough over the northeast/east coast U.S. with an upper shortwave/low crossing out of Canada and into the Great Lakes into tonight. By Thursday morning, the trough in the eastern U.S. and the ridge in the western U.S. both deepen leaving Iowa in a moisture-starved northwest flow with several dry days on tap through the end the week. Before then, there are two low (around 15% or less) chances for a few showers. The first is here this afternoon into early evening in the far north to northeast. Some radar returns are trying to take-off here this afternoon but not expecting them to surmount to much more than a rouge sprinkle at best. Although we are within the periphery of the aforementioned shortwave with some weak forcing, forecast soundings indicate significant dry air and very few have much in the way of moisture over much of a depth. All this to say, it will be challenging for rain to occur/make it to the surface, but won't rule out a few drops in the far north/northeast. A cold front will then follow moving across the area tonight into Wednesday morning. May keep some weak forcing in southern Iowa into early Wednesday morning with the best moisture (though still on the weaker side) into southeast Iowa. The same idea as above applies with dry air keeping precipitation chances low (less than 10%). There are hints of moisture pooling along the front in the low levels though which may manifest as some patchy fog development overnight into early Wednesday morning in at least southern/southeast Iowa.

Behind the cold front, breezy winds out of the northwest are expected on Wednesday with gusts up to around 25 mph. Temperatures will be pleasant and in the 80s through the rest of the work week with a slight warmup on Friday ahead of the next chance for showers/storms to end the week.

LONG TERM /FRIDAY THROUGH TUESDAY/

Issued at 231 PM CDT Tue Aug 25 2026

The upper ridge starts to move eastward on Friday as the eastern trough deamplifies flattening out the flow a bit into the weekend. The surface high pressure also moves off to the east during the daytime Friday. Several rounds of shortwave energy pass through the flow with moisture returning late Friday night into Saturday morning on the nose of the low level jet (overnight Friday night). This will bring the return of shower and storm chances (20-40%) especially west/north. Although there will be dry periods, active weather continues the later part of the weekend into early next week as well with several additional chances for showers/storms. Temperatures begin an upward climb again Saturday into Sunday with heat indices in the 90s on Sunday at this time range.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 630 PM CDT Tue Aug 25 2026

Low clouds that lingered into this afternoon are steadily breaking up and lifting as sunset approaches, such that MVFR conditions are now isolated and quickly fading. Meanwhile, a weak surface trough is approaching from the northwest and will cross the area overnight. This will cause winds to shift to northwest, but at low speeds, then later become gusty by Wednesday afternoon. Late tonight, toward sunrise Wednesday, some patchy fog may develop in southern Iowa. The most likely terminal for impacts is OTM, but even there, the probability is still relatively low and have maintained just 6SM BR in the 00Z TAF accordingly.

DMX WATCHES/WARNINGS/ADVISORIES

None.