182
FXUS63 KDMX 231738
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1138 AM CST Thu Jan 23 2025

 ...Updated for the 18z Aviation Discussion...

.KEY MESSAGES...

- Much colder today with morning wind chills of 5 below to 20
  below.

- Gusty south to southwest winds on Friday as temperatures warm
  to near normal.

- Despite a roller coaster of temperatures, readings get
  progressively warmer into next week. Little chance (<10%) for
  precipitation during this time.

&&

.DISCUSSION...
Issued at 231 AM CST Thu Jan 23 2025

Large eastern trof remains in place this morning with most recent
shortwave having just cleared the state along with the accompanying
surface front.  Temperatures have plummeted early this morning with
readings in the teens south to near zero northwest.  Brisk northwest
winds have pushed wind chills to around 20 below in the north and
these low values are expected to persist into mid morning before
some gradual improvement occurs through the day.  Otherwise, the
strong subsidence and near surface drying has done a good job of
scouring out the stratus near the boundary.  Therefore, at least
partial sunshine is expected for much of the day although with the
thermal trof overhead, temperatures top out 15 to 20 degrees colder
than Wednesday.

Surface ridging slides across the state this evening with warm
advection intensifying overnight into Friday.  Clear skies this
evening along with the light winds associated with the surface ridge
should allow temperatures to drop quickly during the evening,
particularly in the east where some minor snow cover exists.  Have
generally undercut guidance east of Interstate 35 given this good
radiational cooling setup.  However, after midnight, winds from the
southwest slowly increase, most pronounced over the west.
Temperatures are likely to become steady and may begin to rise west
of Interstate 35 during the early morning on Friday and may be
helped by approaching clouds although the bulk of the overcast skies
won`t occur until Friday.

The thickening clouds on Friday are in response to strengthening
isentropic lift across the state associated with the warm advection.
The lowest condensation pressure deficits however remain north of
the state in Minnesota where the best threat for light precipitation
resides.  Otherwise, with the thermal ridge overhead, temperatures
should rebound back to more normal levels by Friday afternoon.  This
back and forth in temperatures continues into early next week with
subsequent shortwaves dropping into the region within the northwest
flow aloft.  However, the northwest flow itself lifts northeast
allowing subsequent warmups to be slightly warmer than the prior
event and temperatures into next week appear to be above normal with
a split flow pattern emerging aloft.  The overall threat for
precipitation remains low given the limited moisture and forcing
across the state during this time.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1130 AM CST Thu Jan 23 2025

VFR conditions prevail for the entirety of this TAF cycle. High
based clouds seen on satellite imagery will continue moving east
southeast before dissipating later this afternoon into the
evening hours. Winds will become less than 10 kts overnight as a
surface high pressure switches winds from the northwest to the
south southwest.

&&

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

&&

$$

DISCUSSION...Cogil
AVIATION...Castillo/Jimenez