282
FXUS63 KDVN 211743
AFDDVN

Area Forecast Discussion
National Weather Service Quad Cities IA IL
1143 AM CST Fri Feb 21 2025

.KEY MESSAGES...

- Our well-advertised warm up continues into early next week.

- A few systems look to move through the area Monday night and
  again Wednesday into Wednesday night, which will bring chances
  (30-50%) of light precipitation

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 254 AM CST Fri Feb 21 2025

An area of high pressure has developed over Missouri early this
morning, leading to a very quiet night of clear skies across the
region, along with light and variable winds. As previous shifts have
mentioned, this has led to some ideal radiational cooling, with
08z/2 AM temperatures around a few degrees of either side of zero,
with measured wind chills this morning in the -5 to -15 degree
range. Wind chills early this morning will continue to range between
-10 to -20 degrees F through 15z/9 AM, so it will be a very cold
morning across the area. Despite another cold morning, these values
are marginal for a Cold Weather Advisory headline, so no plans for
headlines on this shift.

After 15z this morning, our well-advertised warm up will begin,
although it will be much more noticeable by the time we reach Sunday
and especially Monday. This is due to the aforementioned high
pressure system translating to the east, leading to southwesterly
return flow/warm air advection over the area. Highs today will be a
little warmer compared to yesterday, warming to the upper teens
northwest to the middle 20s southeast. Tonight`s lows will once
again be quite cold, but they should remain above zero across the
area.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 254 AM CST Fri Feb 21 2025

Saturday through Monday will remain dry, thanks to mid-level ridging
over the Intermountain West. The main story for this period
continues to be on progressively warmer temperatures. Both the GEFS
and ECMWF ensemble means indicate 850 mb level temperatures to warm
to around 6 to 9 degrees C for most locations by 12z/6 AM Monday.
These values would be around the 90th percentile of the ECMWF
ensemble 850 mb temperature percentiles and the SPC sounding
database, so it will be quite warm for late February. High
temperatures by Sunday look to warm into the upper 30s north to the
upper 40s south, and even some middle 40s to middle 50s by Monday!
Above freezing dew point temperatures return by Sunday and
especially on Monday, which should help accelerate melting of the
current snowpack, and that could lead to some bouts of fog for early
next week due to additional moisture in the boundary layer, so
something to watch for next week. Looks like the warmth will only
continue, with highs remaining in the 40s to even lower 50s through
mid-week.

In terms of precipitation, we are keeping an eye on a few systems
that look to pass through our region, beginning Monday night and
Tuesday morning as a mid-level shortwave trough dives southeast
towards our region as the previously mentioned ridging breaks down.
The global models indicate some slight timing differences, but we
remain confident on the general timing. LREF/NBM ensembles for
measurable precipitation (0.01" or more) chances remain pretty
muted, with generally only around a 10-30% chance and precip type
being all rain. Seems that the better moisture is progged to remain
north of our region. We will have a higher chance (30-50%) on
Wednesday as another wave crosses our region. This shortwave appears
to be accompanied by better moisture, leading to a slightly higher
QPF signal. Again, there are some differences among the guidance for
the areal coverage and timing of the precipitation, but it seems
likely for precipitation to begin as all rain, with perhaps a brief
change-over to snow before ending. Accumulating snow potential
appears quite meager, with NBM probabilities of measurable snow
(0.1" or more) less than 15% across the area. Overall, these two
waves look to bring only light precipitation to our region.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1143 AM CST Fri Feb 21 2025

VFR (SKC) conds can be expected through this taf cycle as high
pressure ridge from MO to KY moves slowly southeast. Meanwhile,
southwest winds around 10 kts will persist through Saturday.

&&

.DVN WATCHES/WARNINGS/ADVISORIES...
IA...None.
IL...None.
MO...None.

&&

$$

SHORT TERM...Schultz
LONG TERM...Schultz
AVIATION...Haase