049
FXUS63 KGLD 132207
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
407 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 302 PM MDT Thu Aug 13 2026

Sunday morning, ridging is favored at 500-mb just to the west of the
forecast area, with its axis running from the Pacific Northwest
through the South-Central Plains. This feature would be supporting a
surface high pressure across the Northern Plains. At the same time,
a broad surface low is forecast to be positioned across the Four-
Corners Region and portions of West Texas. The surface high to the
north and surface low across the Desert Southwest would support
southerly winds meeting northeasterly to easterly winds in Kansas
Sunday. Thunderstorms are possible under this weather pattern. NBM
24 hr precipitation guidance suggests a 25% chance or better for
greater than 0.1 inches of rain across most of the forecast area,
with the best chances across East-Central Colorado and West-Central
Kansas (60-80%). Thunderstorms are not yet expected to be severe, as
LREF guidance shows less than a 30% chance across the entire area
that sfc-500mb wind shear will exceed 30 kts. However, GFS and EC
model soundings show wind shear at or nearing 30 kts. If this is the
case, some thunderstorms may be allowed to become marginally severe.
Confidence in severe weather occurring Sunday is around 5%, though
would increase if wind shear can continue to improve. Regarding
temperatures, highs are forecast a bit cooler in the upper 70s to
mid 80s, as northeasterly to easterly winds would tend to dominate
over the southerly winds from the south.

A strengthening upper level low in Central Canada looks to enhance a
500-mb jet streak across the Northern Plains Monday. This would
allow the surface high pressure to migrate into the Midwest, and
support southerly winds across the forecast area, helping the broad
low to the south. Forecast highs are still in the low to mid 80s, as
the southerly winds look to be relatively weak, and some cloud cover
may still be in place from Sunday`s thunderstorms. Showers remain
possible Monday, but are less likely than Sunday as convergence
reduces across the region. NBM 24 hr precipitation guidance is in
support of this solution, with most areas at less than a 30% chance
to receive greater than 0.1 inches of rain (the exception being West-
Central Kansas in the 30-40% range). Confidence in severe weather
occurring is less than 5%, as LREF guidance continues to show less
than a 20% chance for greater than 30 kts of wind shear across
nearly the entire forecast area.

Deterministic GFS and EC model guidance begins to diverge by
Tuesday, specifically regarding a trough off the United States West
Coast moving inland. Looking at GEFS, EC, and LREF ensembles,
the ridge from the Pacific Northwest to the South-Central Plains
is forecast to remain in place, but flatten out a bit, as the
trough off the West Coast remains off shore through the end of
the period. However, these ensembles show high amounts of
spread in 500-mb heights under and to the east of the trough to
the west, which would suggest the trough is still capable of
moving inland between Tuesday and the end of the forecast
period. About 50-60% of LREF members are in support of the ridge
remaining in place and the trough remaining off the west coast.
If ridging is allowed to remain in place and just to the west
of the forecast area, similar conditions to Sunday and Monday
may remain, with cooler temperatures favored. However, if the
trough is allowed to move inland, temperatures may reach back
into the 90s, and possibly even the lower 100s along the US-283
Corridor. Additionally, relative humidities would have an
opportunity to drop into the 20s based on LREF 25th percentiles.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 401 PM MDT Thu Aug 13 2026

Showers and storms are forecast to increase in coverage as the
evening goes on with periods of moderate to even heavy possible.
Will maintain a PROB30 for now but will AMD with a tempo once
the cluster gets a bit closer to better nail down potential
visibility reductions. Showers and storms are forecast to last
overnight along with some low ceilings developing. MCK remains
most favorable to fall to IFR still. If showers/storms end
sooner then will need to watch for patchy fog.

&&

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

&&

$$

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