textproduct: Des Moines

KEY MESSAGES

- Enhanced (Level 3 of 5) Risk for severe storms in central to eastern Iowa on Friday. Large hail, damaging wind gusts, and tornadoes are possible.

- Much cooler this weekend with overnight lows in the 20s and 30s.

- Mild and dry to start the week with thunderstorms returning to the forecast by late week.

SHORT TERM /THROUGH FRIDAY/

Issued at 243 PM CDT Thu Apr 16 2026

Tranquil conditions across Iowa this afternoon offer a welcome respite from what has been an active weather week. Skies across the area are clear with southerly flow pushing temperatures through the 70s to near 80 this afternoon. In western Iowa drier conditions are in place, allowing for deeper mixing. That has resulted in wind gusts of 20-25 mph this afternoon and relative humidity falling under 30%. This has made for elevated fire weather concerns there, though rapid green up is quickly shutting the door on the fire weather season.

All eyes are on Friday as an amplified upper level trough shifts east with strong associated surface low and cold front. The front is expected to pass across Iowa through the day, pushing into eastern Iowa by around 00z. Breezy conditions ahead of the front with strong southerly flow into the area ahead of the surface low with substantial moisture transport into the area. Soundings indicate 20- 25 mph sustained winds ahead of the front with gusts of 30-35+ mph. The atmosphere will quickly destabilize with 3000+ J/kg of MLCAPE (4000+ MUCAPE) and 7-8+ C/km mid level lapse rates in the warm sector. 35-45 kts of 0-6 km shear will help to organize storms, initially discrete, growing upscale as the line pushes east.

Convective initiation is expected along and head of the cold front in the warm sector on Friday afternoon between 2-4pm. The initial discrete mode will support tornado and hail growth. As storms grow upscale expect the primary hazards to transition over to damaging winds with embedded tornadoes along the line. 0-1 km SRH is around 100-200 m2/s2 in central Iowa, increasing over 300 m2/s2 in eastern Iowa where the tornado threat is highest.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/

Issued at 243 PM CDT Thu Apr 16 2026

Post frontal winds remain strong as the switch around to the northwest with strong cold air advection into the area (plus subsidence and a tight pressure gradient - all the ingredients for breezy winds). Expect post-frontal wind gusts of 20-30+ mph to last through Friday evening and the day on Saturday. The cold front will make for a cool weekend with highs on Saturday in the low 50s. Combined with those breezy conditions, it will not be the most comfortable day for outdoor activities. Saturday night through Sunday morning temperatures bottom out in the upper 20s to low 30s across Iowa and will pose a problem to any sensitive vegetation. Sunday will see light winds and modest temperature recovery into the low 60s. Thermal ridging increases into next week with 70s returning to the area. The week starts of mild and dry, then thunderstorm chances return by late week.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 102 PM CDT Thu Apr 16 2026

VFR conditions will prevail through the TAF period. Winds begin to increase overnight and early Friday morning. This may result in a brief period of LLWS at northern sites, however do not expect it to quite meet requirements. Wind gusts of 20-25+ kts are possible with southerly winds ahead of the front, shifting to northwest behind the front that will pass across Iowa through the day on Friday. Thunderstorms will develop with the front as it passes across Iowa Friday afternoon. Impacts will be included in future updates.

DMX WATCHES/WARNINGS/ADVISORIES

None.