394
FXUS63 KGLD 200733
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
133 AM MDT Mon May 20 2024

.KEY MESSAGES...

- Strong to severe storms remain forecasted for today/tonight
  with hail around two inches in diameter and wind gusts around
  70 mph possible. A severe thunderstorm watch is in effect for
  far SE/E counties.

- Storms; some severe north of Interstate 70 are forecast
  Monday. Main hazards are large hail, damaging winds and
  torrential rainfall.

- Cooler with frost concerns mid week.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 240 PM MDT Sun May 19 2024

Across the region this afternoon, skies are a mixed sunny down to
partly sunny. Not much remains from the morning veil of low cloud,
as storms are starting to develop around the outskirts of the CWA.
Temperatures as of 200 PM MDT are ranging in the 60s and 70s. The
cooler temperatures are those locales still being affected by
clouds. Winds are southerly with gusts into the 20-30 mph range at
times.

The main wx threats in the short term period continue to be focused
on strong to severe thunderstorms potential this afternoon/evening,
as well as Monday/Monday evening and possibly on Tuesday.

For this afternoon/evening, the storm threat will focus on the
environment east of a dryline around the Palmer Divide. Morning
rainfall east may have helped to stabilize portions of the region,
but with storms popping up around the outskirts of the CWA, any CIN
from this morning is quickly eroding. In the south and west, SBCape
has already jumped to 3000-4500j/kg, DCape in the 1000-1300j/kg
range and with high dewpts still over the CWA, the airmass is primed
for storms. SPC has a Severe Thunderstorm Watch out for KS counties
from Graham southwest to Greeley. The main activity should stay east
of these counties. It will be the storms that are forming along
dryline/front which is slowly pushing towards the CO/KS/NE border.
Hail/wind still main threats, but can`t rule out an isolated tornado
or land spout. Heavy rainfall continues to accompany any storms that
have occurred, so flooding still occur.

Storm activity tapers by 06z tonight, allowing for clouds/precip to
clear from west to east. Guidance is hinting at some fog potential
east, so have a mention in around 12z Monday.

As with past model runs, the Mon-Tue timeframe will continue to
focus rw/trw activity mainly north of I-70, especially north of
Highway 36. the aforementioned front/dryline does develop a low on
its southern edge, settling south of the CWA Monday. A couple
shortwaves will move eastward along the northern tier late Monday
and again late Tuesday. The currently track will focus the highest
pops(80-90%) from Highway 36 north. Ample low level moisture on
Monday along the surface feature will interact with the passing
shortwave to trigger convection. There are Slight/Marginal risk
areas, divided by I-70. Wind/hail threats look most impactful.
Isolated tornadoes can`t be ruled out either. Tuesday will see
similar conditions, ending with a cold frontal passage during the
day.

Accompanying the storm threats, will be the potential for torrential
rainfall. The pace of these storms through the CWA this morning has
been mixed and did allow for 1-3" of rain in northeast zones. WPC
does have a Marginal Risk for Excessive Rainfall mainly east today
and for Monday, Highway 36 north. The shift to the Mon-Tue rain
setup will put most areas in flooding potential, especially those
seeing ample QPF today and tonight.

For temps, looking for daytime highs on Monday to range from the mid
70s north into the lower and mid 80s south especially along/south of
Highway 40. With the slow passage of the cold front, Tuesday will be
much cooler with highs ranging from 60F in the northwest to the mid
70s in the south and far eastern zones. Central portions of the CWA
will see a mix of 60s.

Overnight lows tonight and for Monday night will have a range from
the mid 40s west into the mid and upper 50s east. Tuesday night
however, with a cooler airmass still in place, upper 30s to the mid
40s are expected west of Highway 25. East of there, mid to upper
40s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Issued at 133 AM MDT Mon May 20 2024

An active weather pattern continues into the long term period as a
series of shortwaves move through the region, providing additional
chances (generally around 20-30%) for showers and storms.

At the start of the long term period, an approaching shortwave
trough is lending to southwesterly flow aloft as an upper low is
centered near the borders of ID/WY/MT. A surface low is forecast in
the lee of the Rockies by Thursday afternoon-evening with model
guidance suggesting convection developing out ahead of it. Friday
will again see chances for showers and storms as another shortwave
progresses through the flow during the afternoon-evening. Lesser
confidence as we head into the weekend; however, guidance keeps
shower/storm chances with a wave moving through in the Saturday-
Sunday timeframe. As mentioned previously, better moisture and
instability is forecast to reside across eastern portions of the
area during much of the period.

Regarding temperatures, highs are forecast in the low to middle 80s
for Thursday, cooler in the 70s for Friday, followed by a mix of
middle 70s to low-middle 80s through the remainder of the long term.
For low temperatures, expecting generally middle 40s to low-middle
50s.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 1041 PM MDT Sun May 19 2024

Due to the light winds and recent precipitation that has
increased dew points, patchy to locally dense fog many form
tonight and impact both KGLD and KMCK around 8-13Z. Dropping
into IMC cannot be ruled out, but currently fog more dense than
3 mile visibility looks to be fairly uncommon due to a slight
breeze. Around 13Z, the fog will be lifting and become a stratus
deck, lasting until around 18Z. IFR ceilings are looking very
possible early in the morning that will slowly lift to MVFR and
then VFR by about mid-day. In the afternoon hours, starting
around 20Z, showers and storms will move into the region from
the northwest. These showers and storms currently look to linger
until the end of the TAF period.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...Flood Watch from this evening through Tuesday morning for
     NEZ080-081.

&&

$$

SHORT TERM...JN
LONG TERM...CC
AVIATION...CA