textproduct: Des Moines

KEY MESSAGES

- Cold front passage on Thursday brings breezy conditions and large high temperature gradient over the state. Elevated fire weather concerns due to gusty winds mainly in southern Iowa.

- Few showers possible (20 to 40%) behind the cold front on Thursday. Isolated thunderstorm possible in southeastern Iowa, but greatest storm risk is outside our area.

- A cooldown is expected Friday, then gradually warming through the weekend into early next week, while remaining generally dry.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 255 PM CDT Wed Mar 25 2026

Surface analysis this afternoon shows a broad area of relatively weak low pressure over the Central Plains, which will continue to slowly track eastward. A closer look at surface obs depicts a subtle boundary in relation to this feature, which is identified by a very subtle wind shift from southwesterly across the roughly the southeast half of Iowa, and to westerly northwesterly over the northwest half. Despite this weak boundary, conditions are expected to remain dry through the rest of the day given the dry air overhead. On the larger scale, mid-level ridging over the western CONUS remains dominant today, with a large airmass of warm air over the Desert Southwest extending into the western Central Plains. Pacific moisture streaming into Iowa has allowed for patchy cloud cover across portions of the forecast this morning, but has since decreased in coverage somewhat, allowing for more areas to clear up and get some sun. This clearing, along with southwesterly flow at 850mb has overall led to an nice increase in temperatures across Iowa this afternoon, with values in the mid to upper 60s north and through the 70s into central to southern Iowa. Despite an increase in gulf moisture allowing for an increase in dewpoints into the 40s, these values along with warmer temperatures have still allowed for RH values to drop into the 30s, which along with breezy winds and dry fuels have lead to some fire starts over central Iowa. Similar conditions through the rest of the afternoon to early evening may result in continued elevated fire weather concerns, but is expected to remain fairly isolated in nature.

By Thursday, another mid-level shortwave and associated surface low over Nebraska is expected to push eastward into Iowa through the morning, before being shoved south/eastward later in the day as a frontal boundary in relation to this system tracks down across Iowa. Ahead of this frontal passage though, the warmer air mass over the southwestern CONUS will also shift eastward into Iowa, with increasing southwest flow allowing for a push of even warmer air into the region. The extent of warming though will still largely depend on how quickly the front moves across the state through the day. A look at latest guidance showing this front through generally areas north of I-80 by 1-2pm, the greater majority of Iowa, outside of the far southeast by 6-7pm. This trend would indicate that temperatures will have enough time especially over the southern half of the state to warm through the 70s, and even through the 80s near the IA/MO border, while cooler in the upper 50s to low 60s over northern Iowa. Breezy winds with warming temperatures across Iowa, along with RH values in the 30s over southern Iowa will lead to another day of elevated fire weather conditions through the afternoon. In terms of precipitation chances with this frontal passage, model soundings continue to indicate limited moisture in the low levels, as well as capping issues which would largely inhibit much in the way of shower and storm activity through much of the day, despite broad forcing for lift that is indicated. Into the early evening, CAM guidance suggests convection developing mainly over eastern/southeastern Iowa along and just behind the front, where slightly better moisture over these areas is suggested to originate. Instability values around 1000 J/kg+ per NAM/RAP and rather strong shear over far southeastern Iowa into the afternoon before shifting further south and east into Illinois/Missouri. Cannot rule out the potential for a few strong and isolated severe storms in far southeast Iowa for a short period in the evening, if storms can develop, which given the overall setup seems conditional. Along and behind the frontal passage will bring a push of CAA into the region, which will come with gusty north/northeast winds gusting to 20-30 mph with isolated values up to 35-40 mph.

LONG TERM /FRIDAY THROUGH WEDNESDAY/

Issued at 255 PM CDT Wed Mar 25 2026

Widespread north/northwesterly flow remains Friday following the departing front to the south/east, with a large area of high pressure descending across the region. Much cooler and drier conditions are expected for the day, with forecast highs in the low 40s north to low 50s south. The aforementioned surface high is slated to slowly depart the region through Saturday, with a return to mid-level ridging across the western CONUS once again. At the low levels, this means another warming trend on the horizon, as warm air advection pushes warmer air back into the state into early next week as forecast highs are expected to top out through the 70s.

The signal remains for the overall pattern to turn more active moving into the beginning of April as long range guidance depicts at least a few defined troughs ejecting into the Central Plains. Something to continue monitoring over the coming days.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 613 PM CDT Wed Mar 25 2026

VFR conditions and mostly light winds will prevail overnight. A cold front will settle through Iowa on Thursday and will lead to gusty north to northeast winds with fropa. Cigs will begin to lower as well and could lower to MVFR in addition to scattered rain showers. At this time, the confidence in MVFR cigs and precipitation at any site remains low enough to exclude from this forecast.

DMX WATCHES/WARNINGS/ADVISORIES

None.