021
FXUS63 KEAX 121456
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
856 AM CST Wed Feb 12 2025

.KEY MESSAGES...

- Winter storm is ongoing with a total 3 to 6 inches forecast. A
  period of moderate snow is expected this morning when the bulk
  of the accumulation will occur. The morning rush will be
  significantly impacted. Light snow will continue into the
  afternoon before ending this evening.

- Very cold conditions tomorrow morning. Wind chill values
  ranging from zero to 15 below zero.

- Another storm affects the region this weekend. Precipitation
  Saturday may transition from rain to snow with light
  accumulations possible.

- Yet another system is possible late Monday into Tuesday with
  another round of accumulating snow possible.

&&

.UPDATE...
Issued at 855 AM CST Wed Feb 12 2025

* Updated the forecast to decrease any additional snow amounts
  and to add some freezing drizzle.

Satellite imagery shows colder cloud tops (-20C and colder)
shift east of the area with the stronger ascent. Cloud tops of
around -10C to -15C are moving over the area. This is acting
similar to a dry slot (like we`d have if had a cyclone/ closed
low rather than a progressive open shortwave) and has eroded
much of the cloud ice available for the remaining ascent. The
result is the heaviest snow has wound down and we`re seeing
freezing drizzle develop. Upstream satellite imagery does show
some spotty streaks of -15C to -20C cloud tops in central KS and
that will continue to lead to some potential for more scattered
snow. Overall, it looks like we could potentially another inch
of snow, mainly south of Highway 36, with up to 2 inches north
to the IA state line.

&&

.DISCUSSION...
Issued at 246 AM CST Wed Feb 12 2025

A winter storm is ongoing early this morning...generally weak
isentropic ascent has lead to light snow for most of the area
early this morning. However models indicate a stronger mid-level
shortwave is expected to eject out ahead of the main upper
trough and move into the area around 10Z providing additional
lift for increased snow rates. This is supported by current
radar reflectivity trends across central Kansas where steady
light to moderate snow is falling. This feature will provide the
period of heaviest snowfall which is expected to occur between
10Z-15Z when the bulk of the snow accumulations are expected to
occur. This would cause hazardous travel conditions for the
morning rush. As we get into later this morning and afternoon
broad ascent associated with the main upper trough will keep the
potential for light snow around with only minor additional
accumulations. All told, 0,20"-0.40" of QPF is expected with
snow ratios ranging from 12:1 across the southern CWA with
ratios closer to 20:1 across the northern CWA. This will yield
snow totals generally in the 3-6" range. This system is expected
to shift east of the area by this evening. In its wake a
surface ridge of high pressure is expected to begin to build
into the forecast area from the central Plains. This will
provide for a cold night with temperatures in the single digits
with a few spots perhaps dipping below zero. In addition, wind
chill values are forecast to range from the single digits below
zero to nearly 15 below. High pressure is then expected to
remain over the area Thursday providing for weak mixing and with
a fresh snowpack in place highs will be well below normal in
the upper teens to mid 20s. Tomorrow night the surface ridge
will slide east of the area and WAA will begin in earnest. Lows
Thursday night will bottom out in the teens but rise through the
overnight. WAA will continue into Friday will highs rising to
near season normal with highs in the mid 30s to lower 40s.

The next chance for precipitation will arrive Friday afternoon as a
weak upper level shortwave ejecting out ahead of a deepening trough
over the central Rockies will move from central Kansas into southern
Iowa. This will bring the chance for a light rain/snow mix across
the northern CWA however no accumulations or impacts are expected.
Friday night is expected to remain mostly dry however, saturday the
aforementioned upper level trough will shift from the eastern
Rockies into the Plains. This will force a cold front through the
area. This is expected to produce a rain transitioning to snow
event. However, snow accumulations should be limited as NBM
probabilities show only a 20%-40% chance for 2 inch or more Saturday
into Saturday night. Strong CAA behind the front Saturday into
Saturday night will drop lows back into the single digits for most
of the area by Sunday morning. A surface ridge of high pressure will
build into the area on Sunday making for another very cold day with
highs in the teens to lower 20s. The surface ridge will remain over
the area Sunday night allowing lows to drop into the single digits
above zero to single digits below zero.

Another system is expected in the Monday/Tuesday timeframe. Models
are fairly similar with this leading to some confidence despite the
long lead time. Both the GFS and EC advertise very light snow across
northern Missouri Monday into Monday night as subtle shortwaves in
WNW flow aloft introduces those chances. A stronger shortwave is
evidenced moving into the area Tuesday into Tuesday night which
would produce another round of measurable snow. The GFS has more
moisture with the system than the EC thus higher snow however, the
NBM has a 40%-50% of producing more than 2". And, with very cold
temperatures expected on Tuesday mid teens to mid 20s snow ratios
would be expected to be high allowing snow to accumulate quickly.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 539 AM CST Wed Feb 12 2025

MVFR ocnl IFR cigs with lgt-mod snow is expected thru 14Z
reducing vis to 1-2SM and occasionally down to 1/2SM in mod
snow. Aft 14Z...MVFR cigs are expected to persist with lgt snow
reducing vis to 2SM til 21Z-23Z when snow is expected to come to
an end. Aft 21Z-23Z MVFR cigs are expected to cont thru 07Z-09Z
before they sct out becmg VFR. Winds will be out of the north at
10-15kts before becmg NW btn 5-10kts aft 07Z-09Z.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...Winter Storm Warning until 9 PM CST this evening for
     MOZ001>008-011>017-020>025-028>033-037>040-043>046-053-
     054.
KS...Winter Storm Warning until 9 PM CST this evening for KSZ025-
     057-060-102>105.

&&

$$

UPDATE...CDB
DISCUSSION...73
AVIATION...73