880
FXUS63 KGLD 171804
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1204 PM MDT Mon Aug 17 2026

.KEY MESSAGES...

- Isolated to widely scattered storm chances through mid week. A
  few severe storms will be possible in the afternoon and early
  evening with large hail and damaging winds.

- Near to slightly above normal temperatures today and tomorrow,
  then near to slightly below normal Wednesday and Thursday.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 1200 PM MDT Mon Aug 17 2026

A broad upper ridge stretching from the Four Corners to Texas
will move little today and tomorrow. It will consolidate over
the Four Corners Wednesday and Thursday and begin to amplify.
The central plains will remain on the periphery of the ridge
with a zonal flow tending to become more northwesterly as the
ridge amplifies later in the period. Embedded disturbances will
result in at least some chances for showers and thunderstorms
each day. Additional storms may move off the higher terrain to
the west.

For today, latest CAMs are not showing much convection in the
area. An isolated storm or two may develop along the lee trough
in northeast Colorado this afternoon, but fade by sunset. Most
of the activity will be well to the north in Nebraska and the
Dakotas tonight.

On Tuesday, a weak surface trough or front will move through in
the morning with winds shifting to the north. It will have
minimal impacts on temperatures, but may be the focus for
isolated convection in southern parts of the area in the
afternoon where it will stall out. The environment will be
moderately unstable with 2000-2500 j/kg of SBCAPE and 30-40 kts
of deep layer shear. While overall forcing is rather weak and
coverage on the low side, any thunderstorm that develops in this
environment will have the potential of producing large hail and
damaging winds. Appears to be somewhat better chances tomorrow
night for scattered storms moving across the area out of
Colorado. There is some weak isentropic lift/low level warm air
advection after 06z which may keep the storms going through the
overnight. CAMs have varying solutions on how strong the storms
will be, with a fairly weak low level jet at less than 20 kts
but lingering MUCAPE of around 1500 j/kg. While an isolated
marginally severe storm cannot be completely ruled out tomorrow
night, the overall severe threat appears to be low.

As noted above, Wednesday and Thursday will be more of a
northwest flow regime, with a weak to moderately unstable
environment each afternoon along with around 40 kts of deep
layer shear. Forcing somewhat nebulous once again, but in
addition to any embedded wave in the northwest flow, appears to
be a surface boundary in the area on Wednesday which could be a
focus for initiation. CAMs show an isolated storm or two after
about 22z which may pose a large hail and damaging wind threat
given the environmental parameters. Additional storms may move
in from Colorado Wednesday evening, mainly south of Interstate
70. On Thursday, CAMs suggesting storms may be more isolated
with the strengthening ridge. Mean storm motions also become
more northerly which may take Front Range convection more
southward rather then eastward across the plains. Environmental
parameters remain favorable for severe storms should they
develop, but confidence is low at this time.

Temperatures will be near to slightly above normal today and
Tuesday, followed by a slight cool down on Wednesday with highs
in the mid 80s, before returning to near normal on Thursday with
highs around 90.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
Issued at 219 PM MDT Sun Aug 16 2026

Northwesterly flow is favored overhead at 500-mb Wednesday morning
according to GEFS and EC ensembles. A shortwave trough embedded in
the northwesterly flow is forecast to move through the area
throughout the day. GEFS and EC members are in support of a surface
low at the leading edge of this shortwave already past the forecast
area by morning, which would favor a northerly component to the
surface winds. High temperatures are favored to be cooler than
Tuesday, in the low to mid 80s. In addition, thunderstorms are
possible Wednesday ahead of a secondary cold front. NBM 24 hr
precipitation guidance shows the best chances for greater than
0.1 inches of rain across Eastern Colorado and Southwestern
Nebraska, with some areas at a 50-60% chance. These
thunderstorms would be supported by a modest 40-50 kt jet streak
at 500-mb, particularly across northern portions of the
forecast area. LREF guidance is in support of this solution,
showing a two in three chance that sfc-500mb wind shear will
exceed 30 kts for areas along and north of I-70, and as high as
an 80-90% chance across Northeast Colorado and Southwest
Nebraska. As such, severe thunderstorms, particularly across
this zone where wind shear would be highest, are possible. The
favored mode for these storms are currently clusters and/or line
segments, as supported by vertical wind shear parallel to the
incoming cold front alongside recent RRFS data showing a cluster
and/or line segment coming through the area during the
evening/overnight hours. The primary hazard with these storms
would be strong winds, with a secondary hazard of large hail.
Confidence in severe weather occurring is highest north of I-70,
around 10%.

Northwesterly flow is forecast to persist into Thursday, as ridging
continues to build off to the west. While surface winds may still be
out of the northeast during the day, they are forecast to mainly
stay below 20 mph. This would allow sufficient warming to take place
Thursday afternoon as long as clouds clear out. Otherwise,
temperatures would be able to remain cooler Thursday. Forecast highs
are in the mid to upper 80s, though could reach into the 90s if
sufficient heating can take place. Showers may develop during the
evening hours, though NBM 24 hr precipitation guidance suggests less
than a 20% chance for greater than 0.1 inches of rain across nearly
the entire forecast area. LREF guidance continues to show a two in
three chance that vertical wind shear will be above 30 kts along and
north of I-70 Thursday, which may allow some storms to become
severe. However, given the anticipated low coverage of storms
Thursday, confidence in severe weather occurring is 5% or less.

The remainder of the forecast period looks to be dominated by warmer
temperatures as ridging from the west moves in overhead. Highs
Friday through Sunday are forecast in the 90s. Conditions are also
forecast to be drier, as NBM 24 hr precipitation guidance continues
to show a 20% chance or less for greater than 0.1 inches of rain
across the forecast area. Additionally, relative humidities (RH) may
drop a little bit with the increase in temperatures, but are not
forecast to drop below 20%. We may see RH values drop further into
the teens if southwesterly surface flow can develop across the area.
This would be possible given the persisting northwesterly upper-
level flow to the north and east of the forecast region, which would
allow surface lows to track across this area. Even so, fire weather
conditions are not expected, as wind gusts are forecast to remain
below 25 mph all three days. However, if RH values can drop into the
teens and a few thundershowers could develop, there would be a risk
for dry lightning to start fires.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1104 PM MDT Sun Aug 16 2026

VFR expected to prevail at both KGLD and KMCK through the TAF
period with light winds and occasional high clouds.

&&

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

&&

$$

SHORT TERM...024
LONG TERM...Davis
AVIATION...024