Colby, Kansas Weather Forecast Discussion

822
FXUS63 KGLD 292240
AFDGLD
Area Forecast Discussion
National Weather Service Goodland KS
440 PM MDT Mon Sep 29 2025
.KEY MESSAGES...
- Unorganized showers and storms (20% coverage) will develop
  over eastern Colorado late this afternoon and early this
  evening. Severe weather is not expected. Activity will weaken
  and dissipate within a few hours after sunset this evening.
&&
.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 1243 PM MDT Mon Sep 29 2025
Surface observations revealed temperatures in the upper 70s to
low 80s and winds gusting 25-35 mph from the south early Monday
afternoon across the tri-state area. Day Cloud Phase Satellite
shows fair weather cumulus development across eastern Colorado
where RAP mesoanalysis suggests a couple hundred J/kg SBCAPE has
materialized thanks to surface heating. Various CAMs suggest
that as 500mb temps cool with a shortwave trough the strongest
updrafts may evolve into a couple isolated thunderstorms by
3-4pm, though fortunately the limited instability and lack of
wind shear suggests nothing organized or severe is probable
(less than 5% chance). Nonetheless, a few instances of gusty
winds (45-55 mph, per HREF ens max) generated via evaporational
cooling beneath cloud bases in a deep inverted V thermodynamic
profile may spawn some blowing dust and hence localized
visibility reductions, though the overall probability is (and
areal extent would be) low.
The gradual loss of diurnally driven instability will cause
storms to abate late this evening, but we`ll keep some clouds
around through most of the night, particularly across Kansas
where the warm conveyor east of the trough axis will maintain
broad isentropic upglide. Together with continued southerly
winds around 10mph, this will inhibit radiational cooling and
should hold low temperatures mainly in the 50s.
The upper level jet stream will split over the Great Basin and
High Plains tomorrow into tomorrow night, and the shortwave
trough responsible for the precip chances in eastern Colorado
this evening will get hung up across the Central/Eastern Plains
- blocked by a ridge anchored across the Midwest. This should
leave us in an area of subsidence which will maintain dry and
mostly sunny conditions during the day tomorrow. Tomorrow night
into Wednesday morning, however, one cannot rule out a stay
shower as a weak piece of energy at 500mb passes overhead and a
40-45 kt 850mb LLJ parks itself over the tri-state region; the
highest chances (~10%) would be east of an Imperial to Tribune
line where the 29.12z HRRR, NAMNest, and RAP13 spit out a few
light reflectivities.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 1243 PM MDT Mon Sep 29 2025
As with Tuesday, the shortwave energy responsible for any
shower development Tuesday night into Wednesday morning should
get held up across the Central or Eastern Plains by the ridge
over the Midwest/Great Lakes - once again leaving the High
Plains in an area of subsidence and favoring sunny, dry, and
seasonably warm (low 80s) conditions on Wednesday. Global
deterministic and ensemble guidance seems to be slowly coming
into better agreement that by Thursday an upper level ridge will
build northeastward out of the Desert Southwest and into the
Plains. The increasing heights and limited clouds should favor
even warmer temperatures with forecast highs now in the mid to
upper 80s both Thursday and Friday, though offsetting the warmth
of "feels like" temperatures will be gusty southerly winds.
Confidence in speeds is naturally only low-medium at that time
range, but deterministic models (especially the GFS) continue to
suggest tight surface gradients and NBM is advertising around a
50-60% chance gusts surpass 40 mph by Friday.
This weekend into early next week, global deterministic models
and their respective ensembles diverge in how they resolve the
upper level pattern. Empirical Orthogonal Functions (EOFs)
suggest the primary source of variance (given by PC1) is in how
fast the ridge shifts east and an upper level trough digs into
the Intermountain West/Great Basin. Some solutions have a
frontal system arriving in the High Plains as early as Friday
night/Saturday, while others suggest it may not be until early
next work week (of 10/6). Whenever that system arrives, we can
expect a temperature drop, breezy conditions, and at least
slight (20%) precipitation chances, but the risk for any
hazardous weather remains unclear at this time. Stay tuned to
the forecast for updates.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 430 PM MDT Mon Sep 29 2025
GLD: VFR conditions will rule through the TAF period, with
ceilings largely confined to cirrus at-or-above 15,000 ft AGL.
Breezy (20-30 knot) south winds will decrease to 10-15 knots
around or shortly before sunset this evening, as vertical mixing
abruptly terminates/shallows in response to loss of insolation
and the onset of the nocturnal inversion. 10-15 knot south
winds will persist overnight. South winds will increase to 15-25
knots late Tuesday morning (~15-18Z) and persist through the
afternoon.. when gusts up to ~30 knots are possible (similar to
today).
MCK: VFR conditions will rule through the TAF period, with
ceilings largely confined to cirrus at-or-above 15,000 ft AGL.
10-15 knot SSE winds will prevail this evening and overnight.
South winds will increase to 15-25 knots during the late morning
and early afternoon (~16-19Z) and persist through the remainder
of the afternoon (similar to today).
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...None.
CO...None.
NE...None.
&&
$$
SHORT TERM...Bumgardner
LONG TERM...Bumgardner
AVIATION...Vincent

NWS GLD Office Area Forecast Discussion