textproduct: Des Moines

KEY MESSAGES

- Critical fire weather conditions today. Red Flag Warning in place for the entire area. Do not burn!

- Windy conditions expected today. Wind Advisory north half of the area. Gusts of 40-55 mph or more, the highest gusts in northern Iowa.

- Rain/snow Thursday into Friday morning. Accumulating snow chances increasing, especially north.

- Increasing winds and falling temperatures Thursday night into Friday with cooler, more seasonal, temperatures Friday into the weekend.

DISCUSSION

Issued at 416 AM CST Wed Feb 18 2026

Mostly clear skies are overhead early this morning as skies cleared quickly behind the showers that past through last evening. For those that even saw precipitation, amounts were generally only a trace which was not enough to change our very dry antecedent conditions and thus the critical fire weather conditions we have in place today. Along with the clear skies, notable dry air is surging into the area with Iowa in the dry slot of the low pressure passing through South Dakota into Minnesota today. The increasing pressure gradient has already caused winds to take off with 3AM observations indicating sustained winds of 10-25 mph across the area and gusts to 40 mph. Sites just upstream have already hit Wind Advisory criteria (45+ mph gusts, 30+ mph sustained) so pushed up the start time of the Wind Advisory a few hours in the northwest as we won't need the days mixing to reach advisory criteria. This is a bit concerning with deep mixing also expected today as soundings indicate the top of the boundary layer near 800 mb with resultant top of the mixed layer winds around 45 knots (50+ mph). Some soundings even indicate deeper mixing like the RAP at Mason City this afternoon with 44 knot winds at the bottom of the mixed layer and 56 knot winds at the top of the mixed layer, which is over 750mb! This would be getting into High Wind Warning criteria, which is not out of the question given the subsidence and drying as well as upstream observations have had sporadic gusts to 60 mph. Confidence in widespread sustained winds over 40 mph and gusts over 58 mph was not high enough to pull the trigger on a High Wind Warning but some sites may certainly reach these higher gusts over northern Iowa. Conditions will be watched closely this morning in case an upgrade is needed. The Wind Advisory was also expanded southward through the US 30 corridor with advisory level winds expected through much of central Iowa, though the entire area will be windy.

The Fire Weather Watch was also converted to a Red Flag Warning for the entire area with high-end critical fire weather conditions noted by the Storm Prediction Center in the Day 1 Fire Weather outlook. With the dry conditions and winds already noted, relative humidity values fall off to at least the teens to 20s (12-22%), but some guidance may suggest that even these values may be too high with some models indicating dew points may fall to the low teens if not single digits. Regardless, the conditions are in place for rapid fire spread.

Temperatures today will still be warm with no notable drop in temperatures behind the frontal passage this morning with highs in the 50s north to 60s south. Warm air advection returns by tonight with clouds increasing into Thursday ahead of the next system off the Rockies. Temperatures tonight may fall off again, in especially the north, however, where skies remain clear.

Lee cyclogenesis occurs over the Plains tonight into early Thursday with the low pushing into the region during the daytime Thursday. It's possible we see some showers in the warm air advection wing but there remains some questions in soundings on how quickly we will overcome our dry air in place today. Timing of any saturation may also dictate precipitation type if it occurs early in the day, but more likely this would be when temperatures are still warm during the early daytime Thursday. The cold air advection (CAA) arrives later Thursday into Friday northwest/west to southeast/east. Precipitation is looking likely in the deformation zone as the low moves through the region and with the CAA, precipitation type may start as rain and then change to a mix and then snow through the day (midday) Thursday into Thursday night. Accumulating snow with the system still looks most likely over northwest into portions of northern/central Iowa but amounts will be tricky as with rain ahead and the warm ground temperatures, these will counteract the actual accumulation of snow. In saying this, forecast amounts range from a trace south to 3-4" north, though again, it will be difficult to fully realize this entire accumulation. Any wobbles in the track and faster/slower timing may change where/when/how much snow occurs, so stay tuned for fine-tuning today. Snow type will be wet so no real concerns of blowing snow, however winds increase Thursday into Friday which may cause some visibility concerns later Thursday into early Friday with any snow falling. Temperatures will be colder, more seasonal Friday into the weekend as highs fall back to the 20s to 30s with largely dry conditions expected as well, though will need to watch a system passing to the south for any wobbles back north.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 541 AM CST Wed Feb 18 2026

VFR conditions ongoing and largely expected to continue through the TAF period. Some SCT MVFR CIGs have inched their way down towards KMCW from the stratus in southern MN but this stratus should largely stay north of the IA/MN border. Gusty winds are the primary aviation concern through the period with sustained winds peaking around 20-30 knots and gusts to 35 to 45 knots later this morning into early afternoon. A few gusts over 45 knots are not out of the question in northern Iowa. Clouds start to increase again in the south tonight into early Thursday before expanding northward late in the period.

FIRE WEATHER

Issued at 1125 PM CST Tue Feb 17 2026

The Fire Weather Watch has been upgraded to a Red Flag Warning for the entire area. The wind is trending stronger on Wednesday and these winds combined with very low relative humidity values below 25% and cured fuels, will lead to critical fire weather conditions. Extreme fire growth could occur with any fires across Iowa on Wednesday.

DMX WATCHES/WARNINGS/ADVISORIES

Wind Advisory until 4 PM CST this afternoon for IAZ004-005-015- 023-033-034-044. Red Flag Warning from 10 AM this morning to 7 PM CST this evening for IAZ004>007-015>017-023>028-033>039-044>050-057>062- 070>075-081>086-092>097. Wind Advisory until 4 PM CST this afternoon for IAZ006-007-016- 017-024>028-035>039-045>050.