278
FXUS63 KGLD 131838
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1238 PM MDT Thu Aug 13 2026

.KEY MESSAGES...

- Strong to severe storms are again forecast this evening with
  damaging winds up to 75 mph possible. Blowing dust may be
  possible as well during the evening limiting visibility to a
  mile or less. Heavy rainfall may continue through the night
  leading to nuisance flooding concerns.

- Storm chances continue through the weekend. Some may be severe
  and perhaps an increasing flooding concern.

- More seasonable temperatures through the weekend.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 1237 PM MDT Thu Aug 13 2026

A surface low is situated across the south east portion of the CWA
this morning as a cold front moves follows in its wake this will
help keep temperatures across northwestern portions of the area
in the low to upper 80s for the day whereas ahead of the front
mid to upper 90s is most likely. On the deformation zone of the
low, mainly showers and weak storms are already developing this
morning across eastern Colorado. This activity is forecast to
push off to the northeast through the morning and early
afternoon but don`t believe it will have any impact on the
afternoon and evening rainfall potential.

Our main show for showers and storms isn`t forecast to begin until
23Z at the earliest. There looks to be two zones that will be the
focus for storms this afternoon. The first will be from the west and
tied to a shortwave from the higher elevations and is forecast to
move WSW to NNE. Wind gusts up to 65 mph and hail around quarter
size looks to be the primary impacts with this. The second is tied
to our cold front this morning stalling out as a stationary front. A
700mb jet is forecast to develop as well and will aid in storm
development. Guidance suggests that some cold pooling may evolve
with these cells and if so wind gusts of 60-70 and perhaps as high
as 75 mph would be on the table as this will be in the area of the
highest microburst composite. Blowing dust still remains a concern
as well especially with any cold pools. Visibility issues under
one mile will be possible with the cold pools as our mixing
heights are forecast to remain around 4000` AGL along with 0-2km
lapse rates being around 8.5-9.0 C/KM and 2-2.5km lapse rates
around 6.0c/km through around 03Z. If a cell can remain isolated
for long enough some large hail threat could develop as well
with hail up to ping pong balls possible as wind shear is
forecast to be around 30 knots. NAMNEST still has a solution
where the southern zone struggle to form. This currently seems
to be an outlier based on what is being seen in 12Z HREF and
REFS paintball but is something that still has to be taken into
account and is the reason for not going higher on rainfall
percentages as well.

Confidence is increasing in both of these areas of convection
merging (should the southern one form) across Sherman/Thomas
counties this evening. This is forecast to lead to some flooding
concerns as well with PWATS of 1.5-1.8 across the area which
anomalously high for the area at this point of August. Corfidi
vectors are forecast to be around 10-20 knots which with the PWATS
in place some areas could see 1 to locally 2 inch per hour rainfall
rates. I did consider a Flood Watch for portions of the area but a
few things are keeping my confidence down to around 30% in flooding
however. The first is kinda obvious but we have been very dry for
several weeks now so we should be able to soak up the water. The
second is that the CAPE looks to generally remain below 500 j/kg
during the time where any flooding will be a concern which brings my
confidence significantly down that the rainfall rates would be
there for . Everything else is there for flooding concerns
however with slow storm motions, long skinny CAPE profiles and
ample mid and low level RH.

Rainfall is forecast to continue through the night but losing
intensity as CAPE continues to wane. Due to overall consensus
with mid level moisture remaining and with the 700mb jet still
in the area will continue rain chances through at least mid
morning Friday. A very similar pattern to this evening is
forecast to remain in place across the area. High temperatures
are again forecast to be in the 80s to low 90s but if clouds can
remain in the area longer then a few degrees may be able to get
knocked off. With the mid level moisture remaining in place
would not be overly shocked if spotty showers could remain
through the day but confidence is not high enough to keep rain
chances going. Similar to today another shortwave is forecast to
move from the southwest across the area. Guidance has shifted
this wave a little further east than what I was seeing yesterday
so confidence in rainfall has increased. Our low level jet
however isn`t as focused on the area so while widespread
rainfall is still on the table it may be a bit more broken up
than what is expected to occur Thursday night. Severe weather
does still look to be a concern with wind gusts up to 65 mph the
most likely hazard. Some guidance does try to convect some
discrete cells with slightly less wind shear in place than today
but higher CAPE values which could lead to a conditional threat
for large hail. Heavy rainfall is again forecast to be a
concern but storm motions are forecast to be quicker than
tonight, but CAPE values are forecast to be higher which could
lead to better rainfall rates. Depending on how tonight pans
out another flooding risk could be in place for those that see
the most rainfall tonight. The event Friday night and perhaps
the severe potential could be a bit longer than tonight perhaps
going past midnight mountain time.

Saturday, high pressure sets up across the eastern southern Plains
which sets up for a nice surge of monsoonal moisture for the area.
Focus is on another shortwave within the mid level flow which will
again be the source for shower and storms development starting
across Colorado. Similar to today a stationary boundary is
forecast to set up which is forecast to also serve as another
forcing mechanism for showers and storms. Watching the
potential for bit better coverage as well during the evening
hours of storms. The 12Z NAM shows a very wet scenario for the
area with PWATS around 2 inches and slow storm motions. Some
severe threat may be possible with winds up to 60 mph and
perhaps hail up to half dollar size but think flooding may be
more of the concern especially if enough rainfall pans out
tonight and Friday night.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 213 PM MDT Wed Aug 12 2026

The long term period begins with approximately southwesterly flow
overhead at 500-mb Saturday morning. A shortwave trough embedded in
this flow looks to support a surface low pressure traversing the
forecast region during the afternoon and evening hours.
Thunderstorms are possible along a cold front behind the low. NBM 24
hr precipitation guidance suggests a 60-80% chance for greater than
0.1 inches of precipitation Saturday across nearly the entire area.
Currently, thunderstorms are not expected to become severe, as GFS
and EC model soundings show less than 30 kts of sfc-500mb vertical
wind shear across the forecast area. LREF guidance is in support of
this solution, suggesting a 1 in 3 chance or less that vertical wind
shear exceeds 30 kts. If severe thunderstorms were able to occur,
they would be most likely across Red Willow County in Nebraska and
Norton County in Kansas, particularly if a 500-mb jet streak to the
north can move into this region. However, confidence remains low
(around 5%) that severe thunderstorms will occur Saturday. Highs are
currently forecast in the 80s and lower 90s, save for eastern parts
of Graham and Gove Counties in Kansas where highs may reach into the
mid 90s.

GEFS and EC ensembles are in support of a ridge building in
throughout the day Saturday from the South-Central Plains all the
way to the Pacific Northwest. This ridge looks to be fully developed
by Sunday morning, and is expected to be in place through at least
Monday night. The ridge axis would initially be just west of the
forecast area, with a surface high downstream in the Dakotas and
Midwest. Northerly/northeasterly winds on Sunday associated with
this surface high may allow high temperatures to drop into the upper
70s to mid 80s across the forecast area Sunday and Monday.
Thunderstorms may continue during this period as well. A surface low
across the Four-Corners Region would support southerly flow across
the Southern Plains, meeting the northerly flow in Kansas to create
a convergence zone. NBM 24 hr precipitation guidance continues to
show a 60-80% chance for greater than 0.1 inches of rain Sunday, but
drops to a 30-50% chance on Monday when the surface high to the
north moves into the Midwest and allows southerly flow to dominate
in Kansas. Even so, LREF guidance continues to show a 25% chance or
less that vertical wind shear will exceed 30 kts across the forecast
region, limiting the severe risk. Confidence in severe weather
occurring either Sunday or Monday is less than 5%.

Forecast uncertainty begins to increase by Tuesday. Ensemble
guidance is in support of the ridge fully moving overhead and
remaining in place for the remainder of the long term period, with
troughing remaining offshore to the west. However, GFS and EC
deterministic suggest that the trough may move in faster,
moving into the Rockies/Northern High Plains Region by Tuesday
night. This is represented in the 500-mb height spread guidance
which shows a large amount of spread developing over this region
going into Tuesday. If this trough can move in, a surface low
could develop in the North-Central Plains, establishing
southwesterly flow across the forecast area. It would then move
southeastward with time, crossing the forecast area Wednesday.
If the ridge is able to remain in place during this period,
highs in the upper 80s to lower 90s could be expected Tuesday
and Wednesday. However, if the trough can move inland Tuesday
and develop a surface low, conditions on Tuesday could be
hotter, with drier conditions as well. A cold front would then
be possible on Wednesday as the low crosses the area. LREF
guidance is about 75-80% in favor of the ridge remaining in
place during this period, which would suggest conditions simply
remaining warm.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1100 AM MDT Thu Aug 13 2026

Overall VFR conditions are forecast through the afternoon. A
localized area of stratus associated with very light rain is
moving through KITR currently and will be very close to
impacting the GLD terminal so did include a tempo in for a brief
period of MVFR ceilings. Wind gust potential is forecast to wane
by the 19-20Z time frame as well. Focus is then on shower and
storm potential this evening and overnight for both terminals.
This is forecast to begin impacting GLD around 01Z and MCK
around 03Z. Should a storm initially impact a terminal then
strong to even damaging winds would be possible along with heavy
rainfall lowering visibilities briefly down to around 1SM. A
more concentrated area of rainfall is forecast after this and
remaining through the night with periods where visibility could
fall to around 2SM. Increasing signal as well for IFR ceilings
for MCK; GLD is a bit more questionable at this time.

&&

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

&&

$$

SHORT TERM...Trigg
LONG TERM...Davis
AVIATION...Trigg