946
FXUS63 KDMX 092328
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
528 PM CST Sat Nov 9 2024

 ...Updated for the 00z Aviation Discussion...

.KEY MESSAGES...

- Intermittent rain or drizzle through early tomorrow morning

- Dry with temps mild temps Sun night through Tuesday

- Rain chances return around Wed (30-45%)

&&

.DISCUSSION...
Issued at 232 PM CST Sat Nov 9 2024

Our weather will be highlighted by a lower amplitude, fairly
progressive pattern through the next weekend with windows for
precipitation a few times a week and temperatures remaining
above normal to a limited degree. At onset this afternoon, a
fairly stacked upper low continues to swirl across NE with an
accompanied upper level jet and mid level dry slot surging
through the MO Valley. An area of rain continues to lift north
across the northeast half of the forecast area early this
afternoon, and aligns nicely with an area of 850-700mb theta-e
advection on the nose a 1-3km moisture axis from MO into eastern
IA. This lift mechanism should exit the area by 00z however with
decreasing mid level moisture and a lower potential for
measurable precipitation. Stratus will linger into the evening
however, and while the best 0.5-1km moisture transport will be
to our east, persistent southerly low level flow and weak lift
may still lead to some patchy light drizzle north. Chances for
measurable precipitation do increase overnight again however
(reaching 60-70% north) as strong kinematic forcing attendant to
upper low traverses the Siouxland area. This should end by late
morning however, leading to a dry period to start the coming
work week. A weak short wave currently off the Pacific NW coast
should reach the MO Valley late Monday, but with nil
thermodynamic support, limited moisture, and only weak
kinematic forcing, the forecast will remain dry.

The next long wave trough of concern will approach the Rockies
Tuesday however and induce strong return flow into the MO Valley
and western IA. Breezy S-SE winds are expected late Tue with
gusts 30+ mph possible northwest. By the overnight hours and
into Wednesday, phased kinematic and thermodynamic forcing will
increase along and ahead of a noted 1-3km cold front aloft.
Moisture will be somewhat limited however, with much of the lift
going into adequate saturation and likely only a narrow ribbon
of precipitation. Thus rain chances are tempered somewhat and
peak at <50% Wednesday morning. Any precip potential should exit
by Wednesday night leading to another round of dry weather and
above normal temperatures through the end of the forecast period
(Saturday).

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 528 PM CST Sat Nov 9 2024

Upper low will traverse from Nebraska through northern Iowa
tonight and into Wisconsin on Sunday. Widespread MVFR to IFR
conditions are expected tonight, especially in northern Iowa
where low ceilings, drizzle and restrictions to visibilities are
expected. As the system passes late tonight into Sunday,
improving conditions are expected with the drizzle/rain ending
with visibilities becoming unrestricted by midday Sunday.
Ceilings remain MVFR for much of the day. Surface winds remain
mostly south to southeast tonight becoming west and increasing
on Sunday.

&&

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

&&

$$

DISCUSSION...Small
AVIATION...Cogil