Area Forecast Discussion
Issued by NWS Topeka, KS

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000
FXUS63 KTOP 230524
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1224 AM CDT Sat Mar 23 2024

.KEY MESSAGES...

- Cooler Saturday with morning lows in the 20s and highs in the 40s
  and 50s.

- A strong system impacts the region Sunday into Monday with wind
  gusts of 50-60mph and severe thunderstorms possible.

- Light snow in north central Kansas Monday with a 20-40% chance
  of 1 inch of accumulation.

&&

.DISCUSSION...
Issued at 252 PM CDT Fri Mar 22 2024

A northern stream wave quickly pushed a cold front through the area
this morning with post-frontal winds becoming gusty from the north.
A mix of clouds and sun and strong CAA has kept temperatures in the
upper 40s and low 50s. Low-level winds become more northeasterly
this evening and overnight, working to advect in higher moisture and
stratus across eastern Kansas. The western extent of this cloud deck
remains uncertain with guidance varying from clouds staying east of
the area altogether to the entire area being impacted by stratus.
Given current observations and satellite trends, went somewhere
between these two extremes. Lows could be slightly warmer if clouds
keep areas blanketed overnight, but continued CAA should still drop
temperatures into the 20s and low 30s.

A colder airmass arrives for Saturday with 925mb temperatures
cooling to -2 to -5 degrees Celsius. A weak and fast moving
perturbation in the flow brings a quick shot of precipitation to the
area on Saturday. Models are a bit slower in the ejection of this
wave, but temperatures initially still look cold enough to support
some light snow before temperatures warm and precipitation changes
over to rain. Dry air in the low-levels will work to evaporate this
precipitation before it reaches the ground, so no impacts are
expected.

A more potent trough moves into the western CONUS Saturday into
Sunday, working to deepen a surface low across eastern Colorado. A
tight pressure gradient sets up across the Plains which, coupled
with a 55-60kt LLJ, will create very wind conditions. Uncertainty
remains in the amount of mixing during the day as mostly cloudy
skies may limit the depth of mixing. If low-level clouds scatter out
ahead of the main trough, deeper mixing and stronger winds are more
likely. A lead wave increases chances for showers and storms Sunday
morning; some of these could work to bring down stronger winds as
well. NBM probabilities for wind gusts of 50mph or greater have
decreased slightly (40-80%), but 75th-90th percentiles of the NBM
still support some 50-60mph gusts. This could necessitate a High
Wind Warning, but confidence in even a watch is too low at this
point.

The best chances for thunderstorms come Sunday evening and overnight
as a piece of the trough takes on a negative tilt as it ejects
across the Plains. The triple point and dryline are progged to be
across central Kansas by late afternoon with lift from the
approaching trough generating storms in this region. Any initial
supercells will likely grow upscale rather quickly as they move
east. Instability isn`t overly impressive (500-800 J/kg), but the
dynamics of this system suggest a high shear/low CAPE severe weather
set-up where any storm could easily mix down severe caliber wind
gusts.

Precipitation lingers into Monday with cooler air on the backside of
the system supporting a change over to snow through the day Monday
across north central Kansas. Recent guidance has shifted the system
farther north with drier air working into the area and limiting
overall QPF. Chances of 1" of snow are 20-40% for areas along and
north of a Concordia to Marysville line. Of note is the continued
strong winds (gusts of 35-40mph) which could lead to some lower
visibility in areas of falling snow. Temperatures cool as another
cold front moves through Monday with lows Tuesday and Wednesday
mornings supportive of a hard freeze. Highs moderate into the middle
of the week reaching back into the 60s by Thursday.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1223 AM CDT Sat Mar 23 2024

MVFR ceilings have persisted longer than guidance has thus far
shown, and observations show little signs of clearing out in the
next few hours. Seems most likely MVFR ceilings will clear sometime
mid to late morning, with VFR conditions persisting afterwards.
Winds gradually veer from northeast to southeast throughout the
period at around 10 kts.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Flanagan
AVIATION...Reese


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