508
FXUS63 KGLD 231046
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
446 AM MDT Thu May 23 2024

.KEY MESSAGES...

- A Red Flag Warning is in effect for Kit Carson, Cheyenne [CO],
  Sherman, Wallace, and Greeley counties.

- Severe thunderstorms may develop generally along and east of
  Highway 27 both this afternoon and evening. 2 rounds of storms
  are possible and all hazards are possible. There is a 35%
  chance of no storms occurring if the air remains too dry.

- A cold front moves through this evening and into tonight
  generally producing wind gusts around 30 to 50 mph. Gusts up
  to 65 mph are possible, but look to be sporadic if they do
  occur.

- Saturday also looks like another day with critical fire
  weather conditions and severe weather possible.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 437 AM MDT Thu May 23 2024

A fairly active day is possible for the Tri-State area today as an
upper low swings through the Northern Rockies with a deepening
surface low pressure system moving off the Front Range. Guidance is
in fairly good agreement that the center of the low should reach the
KS/CO border by the mid to late afternoon hours with the dryline
extending into the first row of KS counties. With sunny skies and
warm air advection from  the southwest warming temperatures into the
80`s and low 90`s, relative humidity behind the dryline should lower
into the lower teens (if not single digits). With winds gusting
around 20 to 30 mph, critical fire weather conditions are forecast
to be met for most counties along the Colorado border. However, the
advancing surface low from the northwest could weaken the flow for
counties along and north of Highway 36 and limit them to only an
hour of critical fire conditions. As such, the Red Flag Warning
remains for counties south of Interstate 70 and west of Highway 27.
However, if observations later this morning show the surface low
progressing slower, the remaining counties along the Colorado border
may need to be added.

In regards to severe weather, the threat area looks to largely be
determined by the position of the dryline. For areas near and east
of the dryline, severe storms will be possible with no inhibition
and the dryline as a genesis point. Towering cu could develop
through the afternoon, but may not initially be able to become
storms as most guidance suggest a fairly dry profile, at least
initially. Dry air entrainment may completely prevent any storm from
forming, especially if low level moisture advection is weak and
confined mostly to near the surface. However, if there is decent low
level moisture advection ahead of the dryline and able to saturate
the lowest km (as suggested by the NAM 3k), the severe weather
threat would increase and would feature very large hail with
damaging wind gusts and potentially a tornado or two. This would be
similar to previous dryline events this year where large hail would
be the main initial threat. Later in the evening, the cold front
would move through and potentially generate additional storms in an
environment that is much more supportive of tornadoes (probably
QLCS) and straight line winds. For tornadoes, SRH would increase to
200-400 m2/s2 and 0-3km shear around 30-40kts, though it may be
parallel instead of normal to the boundary which would keep chances
low. For winds, DCAPE greater than 1250 J/KG, corfidi downshear
around 50-60 kts, and a linear storm motion would allow gusts up to
70 mph. This second line of storms also looks like it would favor
areas from Trenton, NE to Gove, KS and east.

In short all modes of severe weather are possible today, but there
is around a 35% that no storms form in the area if there is enough
dry air entrainment.

For the remainder of the night, cloud cover is forecast to increase
as the cold front moves through the area. The bigger issue tonight
is the potential for wind gusts up to 65 mph in the wake of the
front. Guidance continue to suggest around 8mb or greater pressure
rise this evening and into the early overnight hours as the system
moves out of the area. Most of the wind gusts are currently forecast
to be around 30-50mph, but will have to keep an eye on how the
system leaves and how much the pressure initially drops. Winds will
then lower slowly going into sunrise tomorrow.

Tomorrow, a milder day is forecast with winds continuing to weaken
behind the system and mostly sunny skies. With the cold front`s
passage, temperatures are forecast to warm into the 60`s and 70`s.
Going into tomorrow evening/night, a few showers are possible in
Eastern Colorado as an upper shortwave moves through and low
pressure begins to develop along the Front Range again. Nothing
hazardous is expected at this time. Lows are forecast to drop into
the 40`s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 419 AM MDT Thu May 23 2024

Storms, potentially severe, are forecast for the holiday weekend.
Heading into the next work week, a drying/warming trend is
anticipated as a ridge of high pressure builds overhead.

For Saturday, a somewhat similar setup to Thursday is forecast where
southwest portions of the area will experience fire weather
conditions west of the dryline while elsewhere could see the
potential for development of severe thunderstorms. Storms could
potentially form and progress eastward off the dryline in the
afternoon-evening favoring locations along/east of Hwy 83, but also
will want to monitor the potential for storms developing later in
the evening as some forcing could be provided by the 700-850 mb wave
swinging through possibly impacting more of the area. SPC has placed
areas generally along/east of Hwy 83 in a marginal (hazard level
1/5) risk for severe weather while along/east of Hwy 283 are in a
slight (hazard level 2/5) risk.

The main system remains forecast to move through in the Sunday-
Monday timeframe, providing 30-50% PoPs Sunday. Cooler temperatures
expected before a drying/warming trend at the start of the work week
with ridging building in. More storm chances return Tuesday-
Wednesday as embedded waves traverse through the flow.

For temperatures, middle 70s to upper 80s expected for highs on
Saturday, slightly cooler in the 70s Sunday, then warming again
Monday onward, with 80s for most of the area by Tuesday. Low
temperatures are forecast to be in the middle 40s to low-mid
50s.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 950 PM MDT Wed May 22 2024

KGLD...VFR conditions are expected through the period.
South-southeast winds of 12-15kts with some higher gusts are
anticipated from taf issuance through sunrise. From 12z-00z,
southerly winds will slowly veer to the southwest, gusting up to
30kts. After 01z, winds are currently forecast to quickly shift
to the northwest with gusts up to 35kts as a cold front moves
through. Presently, no precipitation is anticipated.

KMCK...VFR conditions are expected through the period. A
southeast wind up to 10kts is forecast from taf issuance through
13z. From 14z-00z, southerly winds gusting up to 30kts are
forecast. After 01z, winds are currently forecast to quickly
shift to the northwest with gusts up to 30kts as a cold front
moves through. At this time, confidence is too low to pinpoint
when/if the terminal would see showers/thunderstorms in the
vicinity or over the terminal. Presently, it appears the 23z-03z
timeframe would have the best chance based on the latest data.

&&

.FIRE WEATHER...
Issued at 850 PM MDT Wed May 22 2024

Recent coordination with our fire weather partners suggest the
continuance of Fire Weather Watches/Red Flag Warnings until
further notice.

On Thursday, the combination of dry fuels, southwest winds
gusting 20 to 30 mph and relative humidity values as low as 10
percent will create critical fire weather conditions. Therefore,
a Red Flag Warning is in effect for Cheyenne and Kit Carson
counties in Colorado as well as Sherman, Wallace, Greeley
counties in Kansas from 17z-03z.

A strong cold front will move through the warning area Thursday
evening, abruptly shifting winds to the north to northwest with gusts
generally up to 50 mph, possibly as high as 65 mph. This will
create unpredictable fire behavior for any fires ongoing. First
responders stay up to date on the position and timing of the
cold frontal passage should any fires occur.

Despite possible critical fire conditions, we`ll be leaving
Yuma county and Cheyenne county Kansas out of the Red Flag
Warning. These area have been hit hard by high rainfall amounts
in Yuma county a few feet of accumulating hail in spots. NASA
Sport 0-10km soil moisture remains rather high and would likely
not support explosive fire growth at this time. Winds are also
in question this afternoon and may not reach 25 mph.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...Red Flag Warning from 11 AM this morning to 9 PM MDT this
     evening for KSZ013-027-041.
CO...Red Flag Warning from 11 AM this morning to 9 PM MDT this
     evening for COZ253-254.
NE...None.

&&

$$

SHORT TERM...KAK
LONG TERM...CC
AVIATION...99
FIRE WEATHER...99/KAK