Shawnee, Kansas 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

557
FXUS63 KEAX 241128
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
528 AM CST Tue Dec 24 2024

...12z Aviation Update...

.KEY MESSAGES...

* Mild winter conditions through the end of the calendar year

* Dreary Christmas Day possible with drizzle and fog spreading in
  from east. Rudolph`s services will be needed.

* Rain showers Thursday night.

* Additional, but uncertain precipitation chances weekend into next
  week.

&&

.DISCUSSION...
Issued at 402 AM CST Tue Dec 24 2024

Forecast period can generally be summed up as active, but mainly low-
impact with numerous shortwaves of varying strength traversing the
region concurrent with above normal temperatures.

Currently, an upper level split flow pattern resides over the
central CONUS with general mid-upper level ridging north of the area
and a weak shortwave trough progressing into/across western Texas.
Related surface features have yielded a stalled surface cold front
across central Missouri. As aforementioned Texas shortwave trough
pushes eastward, southerly flow south of the surface front will
continue to advect moist Gulf airmass northward and increase light
rain/precipitation chances over central/southern Missouri today and
tonight. By tonight into Christmas Day, as the shortwave trough and
surface reflection slide eastward, low-mid level southerly flow and
isentropic lift will increase over/north of the surface front.
Guidance has remained consistent in this and model soundings too
continue to depict sufficient depth (>1-1.5km) for drizzle to begin
to overspread the CWA. Fog will be likely as well with concurrent
weak/light surface flow. Expect highs today and Christmas in the
upper 30s to 40s and Christmas lows around/couple degrees below
freezing. By the time drizzle and fog potential increases Christmas
day, temperatures are expected to reside and remain above freezing,
helping limit hazardous travel conditions. All in all, a grey and
dreary Christmas for large portions the area as these conditions
spread N/NW.

A second shortwave trough on a bit more northerly trajectory will be
hot on the heels of the exiting initial wave, keeping southerly flow
going and overall conditions overcast, moist, and above freezing
Thursday into Friday. This too will be the best opportunity (40%-
60%+) for accumulating precipitation for the CWA, Thursday night
into Friday, with shortwave passage and best lift more squarely over
the state. Weakly convective showers and a rumble or two of thunder
will be possible and most likely over southern portions of the CWA
with MUCAPE depictions of around 100 J/kg. Expect quarter to half
inch rainfall amounts to be most common in southern areas with weak
instability, tapering off to a tenth of an inch or less as you move
NW. Highs too will push warmer, into the upper 40s to 50s.

The mid-upper level wave train continues Friday night and through
the weekend with potentially a trio moving through the region. Given
prior activity/pair of shortwaves and quick succession of waves in
general, synoptic guidance does show some struggle/variance in
resolving track and strength of activity this weekend. None of the
waves appears to carry much consequence other than light rain
opportunities. Regardless of precipitation, temperatures will remain
mild with highs predominantly in the 50s and lows above freezing.

A more substantial shortwave and subsequent Lee Cyclogenesis is
depicted early next week within the GFS/Euro suites. While path and,
by virtue, precipitation opportunity are uncertain, there is good
confidence in temperatures easing back towards normal early next
week.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 523 AM CST Tue Dec 24 2024

Initially VFR conditions, aside from KSTJ IFR from the get go,
are expected to quickly erode as a stratus deck from the north
continues to slide southward. Timing such that KMCI/KMKC/KIXD
will all go IFR shortly after the initial 12z issuance. Roughly
1230z, 1300z, 1400z respectively for the trio of sites. While
some guidance tries to push back to VFR, those solutions have
not handled reality well overnight. HRRR/RAP solutions have been
more realistic/in line with reality, so have heavily leaned
that direction for the remainder of the TAF period. Meaning,
more pessimistic with regards to improvements. Do have MVFR
returning in the afternoon with some diurnal
improvements/lifting, then returning IFR after 00z. Potential
for ceilings to approach 500ft or less after 06z, but have
withheld those mentions at this point in time. Winds will remain
mostly unidirectional out of the NE/ENE under 10kts.


&&

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

&&

$$

DISCUSSION...Curtis
AVIATION...Curtis