161
FXUS63 KEAX 231734
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
1134 AM CST Mon Dec 23 2024

.KEY MESSAGES...

- Above normal temperatures continue.

- Drizzle and rain expected Tuesday morning; although, the potential
has moved slightly further south and east.

- Rain with isolated thunderstorms possible starting late
  Thursday night into Friday.

- Final days of 2024 look less active.

&&

.DISCUSSION...
Issued at 358 AM CST Mon Dec 23 2024

Low stratus envelopes the area early this morning as moisture
transport flows into the region. Southwesterly flow ahead of a cold
front to the northwest is keeping low temperatures tonight near our
normal highs for this time of year. An upper level shortwave
traverses across NE NM this afternoon deepening a loosely organized
surface lee trough in western OK. This accelerates cyclogenesis
while also diverging low level winds across the MO/KS state line
washing out the cold front as it approaches negating
precipitation potential today.

The northern wave continues off to the east tilting the southerly
flow of warm air and moisture more southwesterly through the
evening. This could play a critical role in the placement and
progression of precipitation which is still expected for at
least Christmas Eve morning. Frontogenesis happens fairly
rapidly this evening into Tuesday developing areas of stratiform
precipitation along the I-44 corridor. Continued upper level CVA
combined with low layer isentropic ascent broadens rain across
southern MO. While lift with the warm front is concentrated
southward along I-44; isentropic ascent extends toward the I-70
corridor. This looks to bring drizzle along and south of I-70
Tuesday morning. A weak surface high limits this drizzle from
progressing further northward. This is likely to result in poor
visibility along and south of I-70 so please be cautious if
traveling.

Most of the precipitation will move out of the area by evening.
Christmas Day remains dry, but gray as a backside ridge moves
through the region. Temperatures settle in the mid to upper 40s
for many. Meanwhile, another upper level trough traverses the
western CONUS entering the Central Plains Thursday. This more
substantial wave looks to tap fully into the Gulf vaulting warm
air and moisture into the region. High temperatures Thursday
elevate to around 50F for most with areas near Butler and
Clinton approaching 60F. Dew point temperatures are likely to
exceed our normal high temperatures. As Thursday evening
approaches, a large scale storm system develops across TX, OK,
and SE KS. Rain moves into the area from he southwest overnight
Thursday into Friday with a few rumbles of thunder possible
early Friday morning. Swift and broad southerly flow keep
advecting Gulf air and moisture northward sustaining showers
and isolated thunderstorms through much of the daylight hours.
PWAT values exceeding 0.8 to 1 inch bring the potential for
heavy rainfall. Weak, but sufficient instability exists for
some these storms to produce sub-severe hail as, being winter,
the freezing level is much lower. This means storms do not have
far to build upward to realize small hail potential.

Complimentary ridging behind this substantial trough calms skies
down as the end of 2024 approaches. Previous model runs kept the
final week of the year fairly active. This was mainly due to model
suggesting several small embedded shortwaves moving across the CONUS
versus the more consolidated higher amplitude longwaves which we
have been observing in practice. Looking at the extended
forecast, models hint that the beginning of 2025 could be a bit
colder as the polar jet looks to settle south of the area for a
period of time; however, continued fluctuations along the
primary jet stream flow axis continue to oscillate temperatures
above and below normal for the foreseeable future.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1128 AM CST Mon Dec 23 2024

VFR conditions building south across the areas as surface
boundary is a bit stronger than previously anticipated. Low
clouds and fog are expected to be contained closer to the I44
coridor, with light northwest-northeast winds through the
period.

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...None.
KS...None.

&&

$$

DISCUSSION...Pesel
AVIATION...BT