979
FXUS63 KDMX 101126
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
526 AM CST Fri Jan 10 2025

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

.KEY MESSAGES...

- System southeast early, then snow showers possible today.
 - Second system Sat night/early Sunday potential for more light
   snow with light accumulations
 - Return to colder weather Monday/Tuesday
 - Bitter cold wind chills Monday and Tuesday morning

&&

.DISCUSSION...
Issued at 305 AM CST Fri Jan 10 2025

.Short Term /Today through Saturday/...

Confidence: High

Reasonable confidence today on the evolution the short term
forecast.  Weak front is currently pushing into southeast early this
morning and has managed to enhance lift along it.  The southern
stream system tracking into northern Missouri and southeast Iowa had
advected enough moisture north to realize a band of light snow and
light freezing rain just along the departing front early today.
Some minor accumulations of light snow or brief period of light
freezing rain in its wake will occur through sunrise in that area.
Some minor travel impacts are anticipated and an SPS has been issued
for that region through around 6 am. Light northwest flow continues
over the region now. Attention turns to a stronger surface cold
front currently over northern Minnesota. This is also evident
aloft with a pool of colder air at H850 entering the far Northern
Plains at 00z. A pocket of minus 15C air over southern Canada
will move southeast today. Scattered flurries have been ongoing
over northern Minnesota early this morning at 0645z and will
dive south today into Iowa by late morning. Most of the afternoon
will see cold air advection and periods of snow flurries/light
snow showers. No accumulation is anticipated other than a
dusting. The HRRR suggests some steeper lapse rates across the
north/northeast this afternoon during peak heating. A few more
vigorous snow showers may occur with brief reductions in
visibility at times as they pass southeast into the early
evening hours. For now, coverage is anticipated to be fairly
spotty and will just pass along to the day shift to monitor for
any specific messaging or targeted SPS, if needed. Other than
that, today will just end up cooler and a bit breezier with
afternoon northwest winds of 10 to 20 mph. Highs are expected to
reach the mid 20s north to the lower 30s in the south. Tonight
will be colder with some breaks in the clouds as a weak ridge of
high pressure builds southeast. Lows in the mid teens over most
of the region from north to south are expected. Our attention
then turns to the upstream wave currently over the Pacific
Northwest. A more vigorous Clipper moving toward the region has
been forecast for a few days and still looks a little more
impactful than todays weak frontal passage. Prior to the arrival
of the system, highs Saturday will warm to the lower 30s over
the region.

.Long Term /Saturday Night through Thursday/...

Confidence: Medium to High

The system will arrive Saturday evening and continue overnight into
Sunday with a weak low tracking into far northern Iowa/southeast MN
by 12z Sunday. An area of warm air advection precipitation in the
form of snow will cross the area overnight with light accumulations
expected. A strong cold front will drive southeast behind the low
during the day Sunday, bringing flurries and much colder air into
the region by late afternoon. Northwest winds will increase to 15 to
30 mph as well. This will push wind chill values down to the single
digits to near zero far north by late afternoon.  The south will see
values in the mid teens to around 20. Sunday highs will be early,
with falling temperatures during the day. Sunday night will be quite
cold with lows around zero north to 10 above south. Early morning
wind chill values north Monday morning will range from 15 to 20
below. Monday will likely be partly sunny with highs struggling to
reach the lower teens north and in the mid to upper teens south.
Another cold front will edge into northern Iowa by 00z Tuesday. This
will push lows down further to below zero readings north of US20
while the central to southern areas see mins in the single digits
above zero. Similar values of wind chill/apparent temperature will
be felt over the region again Tuesday morning. Tuesday will be
another cold day with readings in the lower teens northeast to the
lower 20s southwest. We really only begin to turn the corner on
Wednesday as the high fades east and a slightly milder northwest
flow returns to the region. Highs Wednesday will reach the mid to
upper 20s and by Thursday, as stronger west winds and H850
temperatures rise to the lower single digits aloft, highs should
reach the upper 30s to lower 40s over the area. With the lack of
snow cover on the ground and not much expected tomorrow night into
Sunday, the prospect of a few lower 40s next Thursday is looking
more likely.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 525 AM CST Fri Jan 10 2025

Cigs have improved for most sites early this morning, but will
again fall back to MVFR cat aft 16z north to southeast this
afternoon. Snow showers will develop aft 16z near MCW and build
southeast through 00z. Coverage still a question mark, so have
left mention out of terminals with PoPs less than 30% most
areas. A few might be significant enough aft 18z north/northeast
to briefly lower vsby/cigs. Day crew will need to monitor short
term impacts. /rev

&&

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

&&

$$

DISCUSSION...REV
AVIATION...REV