247
FXUS63 KSGF 121145
AFDSGF

Area Forecast Discussion
National Weather Service Springfield MO
545 AM CST Wed Feb 12 2025

.KEY MESSAGES...

- Winter Weather Advisory in effect until 9 PM today. Ongoing
  areas of freezing drizzle this morning will diminish from west
  to east ahead of the main precipitation event. Take caution
  if traveling and remain aware, even if seemingly in a lull, of
  potential impacts.

- There is a greater threat for freezing rain and/or sleet
  along and south of a corridor parallel to I-44, with highest
  accumulations across the eastern Ozarks. Expect accumulations
  of a glaze to 0.20".

- The greatest snow threat is along and northwest of I-44.
  Expect amounts between 1-4 inches. Much of the snowfall may
  result from a quick band of snowfall rates up to 1-2 inches
  per hour between 6 and 10 AM this morning (30-50% chance to
  see such rates).

- Another round of widespread freezing drizzle looks
  increasingly likely (30-40% confidence/chance) this afternoon
  after the main precipitation exits.

- Another system will move through the region this weekend and
  will bring additional rain and snow chances to the area, but
  any impacts look to be light at this time.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 430 AM CST Wed Feb 12 2025

Current water vapor imagery shows the trough over the western
CONUS really starting to amplify and deepen now. The result is
broad northwesterly flow across our region. A frontal boundary
is currently along the Gulf coast. This will start lifting
northeast a low pressure system develops and brings wintry
precipitation to our area.

Current observations and radar imagery confirm that areas of
freezing drizzle is occurring across much of our area. A glaze
of ice accretion on elevated surfaces, including elevated
roads, have been reported, with slide-offs being reported in our
northern CWA where temperatures are cold enough for ice to
accrete on roads. Expectation is for freezing drizzle to
continue ahead of the mixed precipitation moving in from the
west. The wintry precipitation will then impact almost all of
our CWA for at least some time. A Winter Weather Advisory is in
effect until 9 PM for all counties except Oregon.

The onset of the main precipitation event is currently starting
in SE KS and the I-49 corridor. This will progress eastward
through the morning hours, impacting the I-49 corridor from 6 AM
to 12 PM, the Highway 65 corridor from 7 AM to 1 PM, and the
eastern Ozarks from 8 AM to 3 PM.


Mainly snow expected along and northwest of I-44:

Latest model trends have come in a bit colder with the surface
temperatures. This is the main reason for the southward
expansion of the Winter Weather Advisory. Additionally, though,
this brings the mixed precipitation zone a bit further south
than the previous forecast. This would be along and just south
of I-44 where mainly a mix of rain, snow, and sleet is expected.

Latest HREF and hi-res guidance brings a strong band of near-
surface and 700mb frontogenesis within the precipitation.
Guidance suggests a quick band of moderate snow to move through
with this zone of forcing (and mixed precip/freezing rain
south of I-44). HREF suggests snowfall rates up to
1-2 inches per hour could occur for an hour or two (30-50%
chance). This would put down a quick 1-2 inches on the roads
between 7 and 10 AM between the I-44 and Highway 65 corridors.

Further north along and north of Highway 54, where the
precipitation shield will occur longer, snowfall accumulations
are expected to be around 2-4 inches, with a 10-20% chance of
seeing higher end accumulations around 5 inches, and a 10-20%
chance of seeing lower end accumulations around 1-2 inches. Snow
should exit the region between noon and 2 PM.


Mainly freezing rain and/or sleet south of the I-44 corridor:

Along and just south of I-44, temperatures are expected to stay
below freezing, however, HREF sounding plumes suggest a deep
enough cold layer for mainly sleet and a rain/snow mix. This
will limit accumulations of any kind, but would create some slick
spots during when the precipitation is falling.

Further south, and especially across the eastern Ozarks where
terrain influences a shallower cold layer, soundings support
freezing rain (at least for a brief period at the beginning of
the precipitation event). This is the main uncertainty--how long
the freezing rain period lasts which will influence the amount
of ice accretion. Along the MO/AR border, HREF precipitation
type probs go from 70% freezing rain between 7-9 AM, to 70% rain
after 9 AM. This period looks to be longer across the eastern
Ozarks (generally until 12-1 PM). Forecaster intuition is that
freezing rain will likely last a bit longer than model
forecasts. The lower-end of the HREF guidance gives a 20-30%
chance of sub-freezing surface temperatures every along the
border through noon. Depending on the duration, accumulations
will range from a glaze to around 0.1-0.2 inches.


30-40% confidence in additional freezing drizzle this afternoon:

After the precipitation exits, moisture and lift will linger,
which will force some freezing drizzle for much of the area,
save for along the MO/AR border. Another round of a glaze of ice
will be possible with this, especially on elevated surfaces.
The drizzle is expected after noon through around 7-8 PM,
exiting from west to east in the early


Colder temperatures filter in tonight

Strong cold air advection and drier air will dive through behind
the freezing drizzle. Lows tonight will range from the upper
single digits toward west-central MO, to the middle teens in
south-central MO. If roads are still wet late tonight, a flash
freeze is not out of the question as temperatures drop from the
lower 30s to the lower teens in 6 or so hours.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 430 AM CST Wed Feb 12 2025

Additional rain and snow chances this weekend:

There looks to be a brief warm-up Friday and Saturday as heights
rise ahead of the next wave. There will be strong surface warm
air advection as winds increase to 15-20 mph from the south with
gusts up to 20-30 mph. Temperatures look to reach the 40s
Friday, and the middle to upper 40s Saturday. Lows will be in
the middle 30s Friday night.

The next system looks to move through Friday night into
Saturday (60-80% chance of precipitation). Thanks to the warmer
temperatures, rain looks to be the dominant type for most of
the event. Colder temperatures are expected to quickly push
through again, though, as the system brings a cold front
through. This looks to transition the rain to backside snow
Saturday night. However, amounts appear to be light at this time
as the system will be an Alberta Clipper in nature, and the
snow will quickly progress through. With this setup, no freezing
precipitation is expected.

Colder temperatures move in behind this system with highs in the
20s Sunday through Tuesday, with lows in the single digits to
lower teens.


Long-term slight risk for snow and below normal temperatures:

The WPC has put us in a moderate risk for much below normal
temperatures in the February 19-21 timeframe, with a slight risk
for heavy snow in the February 19-20 timeframe. This means the
snow and cold is not over yet as we move into the extended
forecast.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 545 AM CST Wed Feb 12 2025

A band of moderate snow is currently impacting JLN. Some
thunder and lightning is being reported with this activity. The
band of snow (mixed precipitation to the south) will quickly
progress eastward impacting SGF and BBG between 12-18Z, with the
heaviest periods between 13-15Z. After the winter precipitation
exits, freezing drizzle will filter in behind between 18-00Z.
This is most likely to be non-freezing at BBG until the end of
the designated timeframe.

Confidence is medium-high that LIFR cigs will persist through
much of the period (60-90% chance through 00Z; 30-60% chance
after 00Z). Cigs may lift to IFR after 00Z.

Winds have begun shifting counterclockwise and will settle to
out of the NW after 18Z, increasing to 10-15 kts with gusts up
to 20-25 kts.


&&

.SGF WATCHES/WARNINGS/ADVISORIES...
KS...Winter Weather Advisory until 9 PM CST this evening for KSZ073-
     097-101.
MO...Winter Weather Advisory until 9 PM CST this evening for
     MOZ055>058-066>071-077>083-088>098-101>105.

&&

$$

SHORT TERM...Price
LONG TERM...Price
AVIATION...Price