836
FXUS63 KGLD 140747
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
147 AM 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.

&&

.SHORT TERM /THROUGH SUNDAY 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 /MONDAY THROUGH THURSDAY/...
Issued at 1221 PM MDT Thu Jun 13 2024

Saturday we will see the leftovers over the upper-level low move
through and out of the area. This could sparks up some showers and
lower end storms. The greatest potential hazard would be if this
precipitation moved over areas that had been rained on the previous
couple of day, creating a flooding risk.

Sunday, the low will clear the area and we will be under weak
southwesterly flow aloft. This will give us about a 15-20% daily
chance of precipitation due to shortwaves in the evenings, but
nothing highly organized is expected until the weak flow is
disrupted, likely Tuesday afternoon. Around this time, the pressure
gradient tightens up as the low over the NW CONUS pushes farther
inland. This would work to amplify any disturbances and increase
chances for PoPs. By mid-next week, we could see the low moving into
the Great Plains and sending a cold front through the region. This
would spark up some storms and start cooling temperatures down some.

High temperatures until mid-next week look to be in the low 90s to
low 100s. After the cold front moves through, after Tuesday, we will
likely only warm into the 80s and low 90s. Overnight temperatures
will follow a similar pattern and drop into the 60s to low 70s each
night, save for Sunday night. Sunday night, additional cloud cover
and fairly strong winds from the south are expected to keep
temperatures in the mid 60s to mid 70s. Gusts overnight could get up
to 30 kts. Behind the cold front, lows will cool down into the mid
50s to low 60s.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1050 PM MDT Thu Jun 13 2024

GLD: Aside from a potential for MVFR-IFR ceilings a few hours
on either side of sunrise Friday morning.. and a potential for
thunderstorms Friday evening (00-06Z Sat).. VFR conditions will
otherwise prevail. NE winds at 10-17 knots this evening will
veer to the E (overnight) and SE (Friday).

MCK: Aside from a potential for thunderstorms Friday evening
(00-06Z Sat).. VFR conditions will prevail. NE winds at 10-17
knots this evening will veer to the E (overnight) and SE
(Friday).

&&

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

&&

$$

SHORT TERM...024
LONG TERM...CA
AVIATION...BV