174
FXUS63 KDMX 151135
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
535 AM CST Sat Nov 15 2025

 ...Updated for the 12z Aviation Discussion...

.KEY MESSAGES...

- A cold front arrives today but a mild start will still have
  highs in the 50s and 60s. Gusty northwest winds behind the
  cold front passage.

- Increasing precipitation chances Monday afternoon and night.


- Another round of wet weather possible late next week.

&&

.DISCUSSION...
Issued at 355 AM CST Sat Nov 15 2025

Surface trough is now moving into central Iowa this morning and is
bringing cooler and drier air into the state. The primary cold front
is still upstream over central Minnesota and into South Dakota. That
boundary will reach northern Iowa early this morning and central
Iowa around noon. The thermal ridge aloft is situated over the
southeast half of Iowa while the colder air is back in proximity of
the surface cold front. Temperatures are off to a mild start this
morning with readings ranging from the upper 40s to upper 50s. A
brief mixing induced boost in temperatures will occur with the
current trough passage then highs will be dependent on the
timing of the cold frontal passage. While temperatures will
stabilize over northern Iowa due to the earlier arrival time,
late morning to early afternoon highs will transition to falling
temperatures over the south for the remainder of the day. Gusty
northwest winds with gusts of 25 to 30 mph are expected with
the boundary passage.

A ridge of high pressure arrives tonight into Sunday and will bring
much drier dew points in the teens and 20s to northern Iowa. Despite
the cooler conditions, Sunday should be a pleasant mid November day.
A moderately active weather is on the calendar for the upcoming
week. Several closed upper low pressure systems will dive south off
shore of the Pacific coast before ejecting out towards the Plains.
The first upper low is just off the southern California coast this
morning and that is the system that will bring heavy rain potential
to that area. The speed max and associated vorticity energy rounding
the basin of this upper low, will lift out towards the Midwest on
Sunday and reach the area late Monday into Monday night. Gulf
moisture will stream back north towards Iowa ahead of the system but
it will take time to saturate due to the very dry air arriving as
discussed above and because the surface flow will continue to
originate from the departing high and reinforce that low level dry
air. The overall trend of a warmer airmass than depicted 24 hrs
ago does suggest the snow potential is decreasing. The
hydrometeor loading of the low level dry air mass will drag
temperatures down as saturation occurs. Timing of the initial
mid-level cloudiness will determine high temperature potential
as any opaque cloud cover will hold highs in the 30s and 40s and
likely 5 to 8 degrees cooler than the NBM forecast.

Tuesday and Wednesday are expected to be mostly dry. Then next
system lifting out of California will bring increasing precipitation
chances beginning Wednesday night and especially later Thursday into
Friday. The precipitation type is expected to be mostly rain but
dynamic cooling and a lingering deformation zone could lead to a
late transition to light snow.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 534 AM CST Sat Nov 15 2025

A cold front will move across Iowa today and will bring gusty
northwest winds by late morning and into the afternoon. The wind
will remain northwest overnight while gradually diminishing. VFR
conditions are expected with passing mid to high level clouds at
times.

&&

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

&&

$$

DISCUSSION...Donavon
AVIATION...Donavon