textproduct: Des Moines

KEY MESSAGES

- Gusty winds up to around 40 mph developing late tonight into the day Friday.

- Above normal temperatures over much of next week. Warmest day forecast is Monday with 60s possible in southwestern Iowa.

- Conditions largely dry until Tuesday of next week.

DISCUSSION

Issued at 253 AM CST Thu Feb 5 2026

The main weather themes over the next 7 days will be above normal temperatures will minimal precipitation chances until Tuesday. Early morning GOES-East low level water vapor imagery shows a Rex block with a cutoff low off of Baja California with ridging over the western US keeping Iowa beneath northwesterly flow early this morning. Nighttime Microphysics RGB imagery has mid and high clouds filling in overtop the low level stratus over the state, which will slowly push off to the east through the day today. Thus, the highest temperatures will be over western Iowa due to more sunshine, but also higher 925mb temperatures around 8C as a warm front slides across the state. This will result in highs into the 50s over western Iowa with upper 30s over northeastern Iowa where cloud cover persists the longest and lingering snowpack will keep conditions cooler. Still, high temperatures will be above normal by 10 to 15 degrees at any given location today.

A shortwave trough will drop southeastward in the northwesterly flow and bring a cold front through the state later tonight into Friday morning. Gusty winds will develop behind the front as cold air advection aids in momentum transport of top of mixed layer winds around 40 mph to the surface. As previous shifts have done, winds were increased from the initial National Blend of Models (NBM) guidance with some flavor of 90th percentile NBM from after midnight tonight through Friday afternoon. Peak winds will be shortly before sunrise into the morning hours. While the main precipitation shield will be well east of Iowa, the NAM, Canadian, and HRRR continue to hint at low QPF, showery precipitation reaching some portion of northern or eastern Iowa. Forecast soundings in these parts of the state continue with steepening low level lapse rates behind the front, which allows for low level instability of a few to perhaps 10 J/kg to develop. The streaky QPF field of the HRRR is a telltale sign of horizontal convective roll (HCRs) nature of the precipitation. The moisture depth in the column remains somewhat limited around or under a 1km so its possible that just cloud streets will form vs HCR precipitation. Thus, have kept PoPs below 15% for now.

This weekend into next week, the ridge over the western US will push eastward bringing along its thermal ridge and aiding in pushing the shortwave trough track to the east. This will keep conditions dry through Monday. While temperatures will lower a bit on Saturday as high pressure passes through the region, developing southerly/ southwesterly flow will pump temperatures 20 to perhaps 30 degrees above normal on Monday. NBM probability of highs higher than 60 degrees are above 50% from Sioux City to Des Moines to Ottumwa with higher probabilities the farther southwest in the state one goes. However, with the southwesterly flow, this will open up the door to clouds and precipitation chances, which may arrive as early as Tuesday, and stunt the degree to which temperatures will be above normal into midweek. The variations in deterministic and ensemble models and their run to run solutions in the pattern in the extended is great and results in what may well be too broad brushed chance PoPs into mid to late week.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 524 AM CST Thu Feb 5 2026

MVFR ceilings and spotty high end IFR ceilings are over the northeastern terminals of MCW and ALO at the start of the period, but ceilings will improve into VFR this morning. Otherwise today, winds from the southwest will turn breezy at 10 to 15 knots as they become from the northwest this afternoon. Tonight, a cold front will move through the terminals bringing increasing surface and low level winds and gusts toward the end of the period into Friday. This favors more turbulence versus low level wind shear (LLWS) so have not included any mention of LLWS. In addition, ceilings will lower with MVFR returning to MCW by the end of the period.

DMX WATCHES/WARNINGS/ADVISORIES

None.