574
FXUS63 KGLD 301003
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
403 AM MDT Tue Apr 30 2024

.KEY MESSAGES...

- A marginal to enhanced risk for severe thunderstorms continues
  for the region mainly Wednesday afternoon and evening. Best
  chances for severe will occur east of Highway 25. However,
  confidence is low at this time due to uncertainty on the
  location of a warm front which will determine where storms
  will develop.

- Elevated to Near critical fire weather conditions are possible
  this afternoon area-wide.

- Elevated to Near critical fire weather conditions are possible
  Thursday afternoon for locations along/west of Highway 27.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 240 AM MDT Tue Apr 30 2024

Across the region this morning, skies are mainly clear with a few
spots seeing some passing scattered clouds. With high pressure to
the east of the CWA, winds are southeasterly with gusts up to 20-30
mph at times.

The latest RAP40 500mb analysis and mid level water vapor imagery
are showing west-southwest flow aloft ahead of a shortwave currently
over the central Rockies.

The main wx concerns in the short term period will focus on fire wx
conditions this afternoon and Thursday afternoon. The biggest
concern for the CWA will be the threat for strong to severe
thunderstorms in the Wednesday/Wednesday night timeframe.

For today/tonight, high pressure east and a developing lee-side
trough over the Front Range will keep a southerly gradient over the
area through the day. Gusts up to 25-35 mph are possible area-wide.
Above normal temps with dry conditions will ensue. Please refer to
the Fire Wx section below for more information on fire danger. This
evening/tonight will have the lee-side trough shift eastward in
tandem with the aforementioned shortwave to potential trigger a few
isolated rw/trw(20% chance)in the northern tier zones, especially
Yuma county and areas along/east of Highway 83. Latest CAMs are
showing isolated coverage.

Going into Wednesday, the setup for expected precipitation is
similar to the last couple events. A surface low will develop along
the tail-end of the lee-side trough/front that moves off the Front
Range. The low shifts to the SE Colorado/SW Kansas area, setting up
a southeast flow into the region.

There will be a dryline/warm front that will push into the region,
that will impact area low level moisture initially. 700mb shortwave
moving into the CWA by late afternoon/evening hours will help to
trigger rw/trw. The latest GFS/NAM does have the low lifting slowly
northeast overnight. This will put the southerly fetch to a switch
over to northerly. This could help to stabilize the airmass(low
cloud cover)in northern/western zones, limiting the chance for
strong to severe storms.

Nonetheless, SPC has increased the Marginal Risk area for storms for
areas along/west of Highway 25, Slight Risk remains for areas east,
with a sliver of Enhanced Risk for far eastern locales in Graham/
Norton counties. The latest NamNest has best chances from 05z
Thursday onward for storms. Hail, wind and tornado threats are
possible. Some localized heavy rainfall is possible. Please refer to
the latest Hydro section for further information.

For Thursday and Thursday night, wrap-around moisture from the
exiting system will bring about chances(20-40%) for additional
showers and maybe an isolated thunderstorm, especially during the
daytime hrs. Lower confidence for bigger area coverage as models
have different timing as to the exit of the overall clouds/precip
potential, but can`t rule out at least daytime potential.

For temps, daytime highs today will range from the lower to mid 70s
in the northwest, into the upper 70s to around 80F for areas in the
south-southeast. Going into Wednesday, lower to mid 70s north of the
Interstate, increasing to the lower 80s by Highway 40 and south.
These numbers on Wednesday will be highly dependent on how fast
cloud cover increases/persists with the anticipation of rain. On
Thursday, lower to mid 60s west, into the upper 60s to lower 70s
east.

Overnight lows tonight will range in the 40s, warmest east of
Highway 25. A few spots in the western portions of our northeast
Colorado counties could see the upper 30s, from the Flagler area up
north to the Joes/Kirk area. For Wednesday night, similar to tonight
with more upper 30s expected in western portions of Yuma/Kit Carson
counties. Thursday night, colder with mid 30s west increasing
eastward to around 40F. Some wind chill readings during this time in
Colorado could read in the mid to upper 20s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Issued at 154 AM MDT Tue Apr 30 2024

Upper level ridging over the area with low pressure centered in
vicinity of ID/WY/UT Friday morning will have the area under
southwesterly flow aloft. As the low pressure system progresses
eastward, a front will sweep through the area in the Friday evening-
Friday night timeframe, giving around a 30-50% chance for showers/
thunderstorms. Heading into the weekend, upper level ridging will
build back in with flow becoming increasingly zonal while the next
system comes into view off the west coast. Low pressure will skirt
south of the area, then east on Sunday, and with the low level
easterly upslope flow allowing for increased moisture into the area,
at least expect to see some increased cloud cover but also potential
for increased chances (up to around 20-25%) of showers/thunderstorms.

As mentioned in prior discussion, there continues to be significant
differences in guidance with regards to timing/placement of the
early week low pressure system. Taking a look at ensemble members
for 12Z Monday, placement of the upper low center ranges anywhere
from still off the west coast to over the Desert Southwest to
already encroaching on our area, with the jet streak working
into our CWA. If the low is situated across the Desert
Southwest/Four Corners region during the first half of the day
Monday as currently suggested by majority of the GEFS ensemble
members, could be looking at impactful weather day(s) for the
start of the work week with possible hazards of gusty southerly
to southwesterly winds, fire weather conditions, possible
blowing dust concerns, thunderstorm potential followed by a
frontal passage and wind shift to out of the north. Very low
confidence at present in the potential for an early week multi-
hazard event, so will continue to monitor for better consistency
in guidance as this timeframe comes into closer range.

For temperatures, looking at highs in the middle 60s to lower-
middle 70s Friday and Saturday before warming into the 70s
Sunday, and middle 70s to middle 80s Monday. For low
temperatures, the forecast calls for middle 30s to upper 40s
Saturday morning, low-mid 40s Sunday morning, middle 40s to
middle 50s Monday morning, and low 40s to low 50s Tuesday
morning.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 349 AM MDT Tue Apr 30 2024

For KGLD, VFR conditions expected through the forecast period.
Winds, south around 10kts veering west by 14z. By 15z-16z,
northwest around 20-30kts, becoming north-northeast 10kts by
23z. From 08z Wednesday onward, southeast around 10kts. LLWS
12z-14z 180@50kts.

For KMCK, VFR conditions expected through the forecast period.
Winds, southeast around 10kts through 14z-15z, then veering
west. By 16z, becoming northwest around 20-30kts. By 01z
Wednesday, north around 10kts becoming northeast from 06z
onward. LLWS 12z-15z 200@45kts.

&&

.FIRE WEATHER...
Issued at 241 AM MDT Tue Apr 30 2024

Tuesday afternoon, Elevated to Near Critical fire wx conditions are
possible area-wide. Humidity values will drop into the 17-22% range,
with wind gusts through the day from the northwest around 25-35 mph.
Some localized 40 mph gusts are possible. Rainfall received over the
past week will help to mitigate area fuel moisture concerns.

Thursday afternoon, some Elevated to Near Critical fire wx
conditions are possible for areas along/west of Highway 27. Humidity
could drop into the upper teens, with gusts into the 30-40 mph from
the northwest. Lower confidence for these conditions than for this
afternoon as the amount/extent of rainfall received on Wednesday
will be a key ingredient to benefit/not benefit area fuels.

&&

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

&&

$$

SHORT TERM...JN
LONG TERM...CC
AVIATION...JN
FIRE WEATHER...JN