124
FXUS63 KGLD 141900
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
100 PM MDT Fri Jun 14 2024

.KEY MESSAGES...

- Thunderstorms will develop in northeast Colorado by mid
  afternoon, reaching the Colorado and Kansas border area by 6
 PM MT, and sweeping across the rest of the area this evening.
  The primary hazard will be destructive winds in excess of 60
  mph and locally up to 90 mph. Some large hail may accompany
  initial storm development in the afternoon and early evening,
  as well as a tornado or two, before merging into clusters.
  Locally heavy rainfall will also be possible as well as flash
  flooding.

- There is a marginal risk for a severe storm or two Saturday
  afternoon and early evening in northwest Kansas east of a
  Norton to Leoti line. Stronger storms will be capable of hail
  up to quarter size and wind gusts in excess of 60 mph.

- Return of triple digit heat expected on Sunday.

- Cooler temperatures expected mid-next week.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 145 AM MDT Fri Jun 14 2024

Overnight showers and isolated thunderstorms appear to be the
result of a weak shortwave trough topping the ridge axis. This
activity will continue through this morning as the wave moves
east. May see a break in the precipitation from late morning
through mid afternoon, then convection develops in Colorado
21-22z with the next, and much stronger, shortwave moving out
of the Rockies. Storms reach the Colorado-Kansas border area
around 00z and then sweep through the forecast area Friday
evening. The environment will be moderately unstable, ensemble
mean values running around 2000-2500 j/kg with some pockets in
excess of 3000 j/kg, and deep layer shear of 30-40 kts. CAMs
suggest two possible clusters developing, one in northeast
Colorado that moves northeast into Nebraska, and more of a
linear cluster that moves across northwest Kansas this evening.
Either cluster will be capable of producing wind gusts in excess
of 60 mph, with some of the model output showing gusts of up to
90 mph possible. The potential for destructive winds will be the
main hazard. In addition, large hail may accompany initial
discrete supercells that form before merging into a cluster, as
well as a tornado or two. Finally, heavy rainfall and flash
flooding will become a concern into the evening hours, with 90th
percentile QPF of 2-3 inches from Yuma County, Colorado,
eastward into the Kansas and Nebraska border area. Higher
percentile QPF amounts further south are generally around 1 inch
with the faster moving linear cluster, except in the Greeley and
Wichita county areas where it is around 2 inches. The severe
threat should end by 06z and precipitation ending by around 09z.
High temperatures will be in the upper 80s and lows tonight in
the 60s.

The upper trough axis slowly moves through the area on Saturday,
ending up near the eastern zones Saturday afternoon, with a weak
reflection at the surface. Scattered afternoon thunderstorms
will develop with best chances east of a Norton to Leoti line in
northwest Kansas with weak convergence along the surface trough.
The environment will only be marginally conducive to severe
storms, with instability topping off at around 1500 j/kg and
deep layer shear of around 20-25 kts. Cannot completely rule out
an isolated low-end severe storm or two, but overall severe
threat is low. Storms should move out relatively early Saturday
evening as the trough pushes east. High temperatures will be in
the lower 90s and lows Saturday night in the 60s.

On Sunday, will have a weak southwesterly flow aloft and a warm
front surging northward at the surface. The front will herald
the return of extreme heat, with highs back into the upper 90s
and lower 100s. Assuming the surface front stays north of the
area as the models indicate, in central Nebraska, will only see
slight chances for showers and thunderstorms Sunday night with a
weak shortwave moving through the flow. However, if the front is
further south, precipitation chances may be higher, particularly
in southwest Nebraska. Low temperatures Sunday night will be
in the 60s and 70s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 1259 PM MDT Fri Jun 14 2024

Sunday, the low will clear the area and we will be under weak
southwesterly flow aloft. This will give us about a 15-20% chance of
precipitation Sunday and Monday evenings. Nothing highly organized
is expected until the weak flow is disrupted, likely Tuesday
afternoon. Around that time, the pressure gradient tightens up as
the low over the NW CONUS pushes farther inland, moving the jet
stream fairly close, if not over, the High Plains. This would work
to amplify any disturbances and increase chances for PoPs.
furthermore, at 850mb, the high pressure system over Texas today
looks to stall out over the Mid-Atlantic Seaboard and will funnel
moisture into the region Tuesday through Saturday.

High temperatures Sunday and Monday look to be in the mid 90s to low
100s. Tuesday will start a cooling trend (highs in the upper 80s and
90s), but Wednesday and beyond will likely only warm into the 80s
and low 90s. Overnight temperatures will follow a similar pattern
and drop into the 60s to mid 70s Sunday and Monday nights, and then
cool into the mid 50s to mid 60s Tuesday night and beyond. Gusts
Sunday night through Tuesday morning could get up to 30-35 kts. It`s
also worth noting that while the cooler temperatures look nice on
the thermometer, the additional moisture will make the region feel
more muggy and soupy than normal.

Monday could see some localized critical fire weather conditions in
the extreme southwestern CWA. Winds look to gust near 25-30 kts
while RH values get into the upper teens. This is really the best
chance for critical fire weather conditions as the additional
moisture will keep min RH values above 30%.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1015 AM MDT Fri Jun 14 2024

For KGLD, VFR conditions through 00z Saturday, then a MVFR/VFR
mix through 06z as rw/trw are expected. 4-6sm visibility
reduction in rain, with ceilings down to OVC025 at times. VFR
after 06z Saturday. Winds, mainly south-southeast 10-15kts.
Gusts to 25kts through 00z. Winds briefly go to southwest
15-25kts from 00z-03z. LLWS 03z-06z Saturday 200@40kts.

For KMCK, mainly VFR conditions at this time. The threat for
storms after 00z Saturday could bring in MVFR conditions from
03z-06z. VCTS possible through at least 02z-06z. Winds, south-
southeast 10-15kts. Gusts to 25kts through 02z Saturday. LLWS
02z-06z Saturday 210@60kts.

&&

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

&&

$$

SHORT TERM...024
LONG TERM...CA
AVIATION...JN