904 FXUS63 KDMX 261830 AFDDMXArea Forecast Discussion National Weather Service Des Moines IA 130 PM CDT Fri Sep 26 2025
.KEY MESSAGES...
- Weather on repeat - warm, ample sunshine, and dry conditions until at least the middle of next week.
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.DISCUSSION... Issued at 127 PM CDT Fri Sep 26 2025
There is little change in the forecast thinking today from this time yesterday with a dry and warm period expected into at least the middle of next week. Visible satellite shows no clouds over the state with the eastern edge of the broad ridge fully over the region. There is a robust upstream shortwave trough moving over the Alberta province into the Saskatchewan province with a surface cold front extending through the Dakotas. This front will drop through Iowa on Saturday. As it does so, a wind shift from the southwest to from the northwest or west will occur with slightly breezier daytime winds. Further, highs today to Saturday will be similar over southern Iowa, but about 5 to 10 degrees lower in the upper 70s over northern Iowa. There is no chance of rain as the front is moisture starved with forecast soundings showing this dry air and a precipitable water value under a half an inch. Thus, plenty of sunshine will prevail with this continuing into Sunday as surface high pressure pushes into Iowa behind the cold front.
Dry conditions will prevail through at least the first half of the week as a slowly progressive omega block moves eastward with 500mb lows over the Southeastern US and Arizona and the ridge between the two. The progression and evolution of the Southeast US low will be complicated by AL94`s arrival early next week with this slowing down the flow and causing the upstream ridge to be pinched at the bottom and/or tilted at the top. This will allow the Arizona low to lift northeastward into the Dakotas by midweek with Iowa remaining under lingering ridge influence and light flow keeping conditions dry through midweek if not late next week. Highs most days next week will be in the 80s with lows in the 50s to around 60 degrees.
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.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1241 PM CDT Fri Sep 26 2025
VFR conditions will prevail through the period. Winds from the southwest will become from the south and average 5 to 10 knots this afternoon. A front will bring a wind shift and breezier winds into northwestern Iowa Saturday morning being near DSM/ALO by 18z Saturday.
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.DMX WATCHES/WARNINGS/ADVISORIES... None.
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DISCUSSION...Ansorge AVIATION...Ansorge
NWS DMX Office Area Forecast Discussion