AFOS product AFDDMX
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Displaying AFOS PIL: AFDDMX
Product Timestamp: 2025-10-03 03:45 UTC

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631 
FXUS63 KDMX 030345
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1045 PM CDT Thu Oct 2 2025

 ...Updated for the 06z Aviation Discussion...

.KEY MESSAGES...

- Elevated fire weather concerns this weekend, especially for
  field fires with warm and breezy to windy conditions both 
  days. Any spark could cause a fire in a field, which could 
  spread quickly!

- Increasing chances for showers and storms from late Sunday
  into at least early next week.

- Conditions more seasonal next week.

&&

.DISCUSSION...
Issued at 220 PM CDT Thu Oct 2 2025

The remnant shortwave energy is passing over and away from Iowa
early this afternoon with mid-level ridging returning to the 
region. This will keep our pattern very warm and dry through 
Saturday if not Sunday. Each day during this period may see 
diurnally driven fair weather cumulus clouds, but should 
otherwise be quite sunny with highs well into the 80s to around 
90 degrees. To the west of the ridge, an amplified longwave 
trough is arriving over the Western CONUS today into Friday. 
This trough will aid in the development of surface low pressure 
over the Rockies that deepens through the weekend as it moves 
into the eastern Dakotas. With the pressure gradient tightening 
between this low and sprawling surface high pressure over the 
Eastern US during this period, an increase in winds is expected.
This won't be too noteworthy on Friday as winds at the top of 
the mixed layer will be 20 knots or less, but as the low deepens
and the gradient tightens with southwesterly flow 
strengthening, wind gusts over 40 mph will be possible over 
northwest into perhaps north central Iowa. With the warm and 
windy conditions, the concern will be on fire weather, 
particularly field fires with the cropland fire danger in the 
very high to extreme category. Cropland is cured and with farm 
equipment working to harvest crops, the conditions will be ripe
for fire growth if a spark starts a fire. This could make fire 
departments rather busy this weekend.

As we move into Sunday, the longwave trough over the western US
will near Iowa with a shortwave trough pivoting through and out
its base. This will help to bring a surface cold front through 
the state Sunday into Sunday night. With this front and to some 
degree an increase in cloud cover, the high temperatures will be
a few to several degrees lower in the low and middle 80s on
Sunday. Moisture will pool along the front and with the phasing
of stronger thermodynamic and nearby kinematic forcing, will 
aid in scattered showers and thunderstorms developing by later 
Sunday if not by Sunday night. While this boundary will sink 
into Missouri early next week, lingering forcing and isentropic 
lift over the boundary will keep rain chances in the forecast 
through at least Tuesday. During this period, instability is 
generally meager to at best modest with higher deep layer shear 
so any severe weather signal is not readily apparent here or in 
the AI/ML space beyond 5%. While warm cloud depths will be 
seasonally high and precipitable water values may reach 1.5 
inches at times, our dry stretch of weather should allow soils 
to readily soak up any of the anticipated rainfall. 
Deterministic models show a 1 to 2 inch streak across some 
corridor of the state, though the current National Blend of 
Models shows just a 20 to 30% chance of exceeding one inch over 
the three day period ending Wednesday morning. Temperatures will
return to seasonal levels next week as well in the wake of the
front.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1037 PM CDT Thu Oct 2 2025

Little change from previous forecast. VFR conditions prevail
this evening, with light southerly winds overnight. Winds pick
up slightly tomorrow, generally around 8 to 10 kts with gusts up
around 15 to 20 kts possible over western Iowa. Skies remain
clear.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Ansorge
AVIATION...Dodson