347
FXUS63 KGLD 241117
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
417 AM MST Tue Dec 24 2024

.KEY MESSAGES...

- Moderate confidence in fog developing Christmas Eve night
  through Christmas morning in Northwest Kansas and Southwest
  Nebraska. The fog could be dense with visibility to a quarter
  of a mile or less at times.

- Continued 20%-30% chance for light rain showers Christmas
  night through Friday for various parts of the area. Fog may
  also develop during this time period.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 213 AM MST Tue Dec 24 2024

Observations overnight have shown cloud cover across the area
with relatively light winds. The winds are forecast to remain
light through the day with a weak pressure gradient, but the
cloud cover should clear from west to east during the day as a
shortwave ridge moves east near the area. With the cloud cover
clearing and 850mb temperatures forecast to be around 7-9 C, the
forecast currently as high temperatures reaching the mid to
upper 50`s west of Highway 83. East of Highway 83, the cloud
cover could linger long enough to prevent full daytime heating
and keep temperatures more in the 40`s and low 50`s.

Tonight, the upper ridge is forecast to get pushed out of the
area to the east ahead of an upper trough. With the trough
approaching, a surface low is forecast to develop along the
Front Range and increase the surface flow from the south. For
the evening and beginning of the night, the ridge moving over
should keep skies clear. However, as the upper trough brings mid
to high level moisture and the southerly winds bring in near
surface moisture, cloud cover is forecast to increase across the
area with the potential for fog to also develop. The fog is
forecast to mainly develop in Northwest Kansas and Southwest
Nebraska as moisture gets pulled slightly higher in elevation
from the south/southeast. The fog may be dense, though the
higher level cloud cover and winds around 8-15 mph complicate
things a bit. Low temperatures will likely occur near or before
midnight while the skies are clear with temperatures in the 20`s
and low 30`s.

Christmas Day, the upper trough is forecast to move through the
Four Corners region and then towards the Panhandles Region,
along with the surface low. For the Tri-State area, this is
forecast to allow the area to continue to have low level
moisture advection which should allow for fog and/or low cloud
cover through most of the day. As for precipitation chances,
rain is not likely during the day with the moisture forecast to
be confined to the near surface. Even with the low advancing,
anything more than fog or drizzle doesn`t look like it`ll happen
during the day. Ensemble 500mb spread charts still also favor
the trough digging a little further south which could pull the
low farther away from the area. If this occurs, parts of the
area may see high temperatures on Christmas reach the 50`s.
Otherwise, the combination of cloud cover and fog will keep
temperatures in the 40`s. Winds are forecast to be a bit breezy
on the eastern edge of the surface low with gusts between 25 and
40 mph from the south are possible through the late morning and
evening hours. The stronger winds favor Northwest Kansas and
Southwest Nebraska with the center of the surface low forecast
to be near or over Eastern Colorado.

Christmas Night and into Thursday, the upper trough and surface
low are forecast to continue pushing east/southeast. As they
do, the Tri- state area is forecast to briefly be on the wrap
around side of the surface low where we may get some brief rain.
The main issues is that the surface low and upper trough are
forecast to diffuses out and become less deep as time goes on
and the moisture may remain fairly shallow. There is a chance
for some mid-level moisture and maybe some seeder-feeder
depending on how far south the upper low digs. With this, most
of the area is expected to see cloud cover and/or fog through
the day on Thursday, keeping temperatures cool in the 40`s with
maybe a few 30`s.

Late Thursday, there`s some uncertainty with how fast the next
upper trough will move through. If it doesn`t move through until
Friday, Thursday should see clearing skies and calm conditions,
allowing lows to drop into the 20`s and 30`s. Some fog could
still persist along and east of Highway 83 with the surface
moisture being slowly pushed out. If the trough moves through
faster, than there could be some light rain/snow showers with
the next wave moving through.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Issued at 300 AM MST Tue Dec 24 2024

Friday-Sunday: Long range guidance indicates that cyclonic flow
aloft (over the central CONUS) will transition to NW-WNW flow
aloft this weekend.. on the eastern periphery of an amplifying
ridge over the Intermountain West and central-northern Rockies.
Expect a warming trend and above average to well-above average
temperatures.. with highs increasing from ~50F (Friday) to the
mid-upper 50`s (Saturday) and upper 50`s to lower 60`s (Sunday).
For reference/comparison, average high temperatures in late
December are in the lower 40`s (~40-43F). While periodic waves
in NW-WNW flow aloft may yield bouts of mid-upper level cloud
cover and virga.. measurable precipitation is presently not
anticipated.

Monday-Tuesday: Long range guidance indicates a transition to a
more seasonal (winter) synoptic pattern over North America
early next week, a pattern characterized by the presence of a
large, modestly deep (500 mb heights ~525-530 decameters) upper
level low over central-eastern Canada and a powerful (125-150
knot) westerly upper level jet over the central-southern
CONUS.. a jet extending from the Pacific Coast to the Eastern
Seaboard. This type of pattern often results in dynamic/volatile
weather over the central or eastern CONUS. In the immediate lee
of the Rockies (Goodland CWA), one would expect an abrupt
transition to colder temperatures and breezy to strong north
winds. In this pattern, at this range (6-7 days out),
precipitation potential remains obscured.. i.e. cannot be
assessed with confidence (one way or the other).

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 413 AM MST Tue Dec 24 2024

For KGLD & KMCK... VFR conditions are expected for at least the
first 12 hours of the period. Skies are forecast to clear
through the morning with winds around 10 kts through the day
from the south/southwest. Tonight, fog is possible after about
03Z, but with a slightly better chance after 09Z. Confidence in
timing and location of the fog wasn`t high enough to include in
the 12Z TAF, but look for updates in future forecasts. LLWS also
becomes a concern for KGLD as an upper level trough begins to
push in from the west, which is forecast to increase the flow a
few hundred feet above the surface to about 35 kts.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.

&&

$$

SHORT TERM...KAK
LONG TERM...Vincent
AVIATION...KAK