391
FXUS63 KGLD 021141
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
541 AM MDT Thu May 2 2024

.KEY MESSAGES...

- Scattered thunderstorms are anticipated to develop over
  portions of northeast CO and northwest KS Friday afternoon.
  Severe storms capable of producing damaging winds are
  possible, mainly late Fri aft/eve, when storms may organize
  into a squall line that tracks SE toward southwestern and
  south-central KS. Dangerous travel conditions associated with
  widespread strong to severe wind and significant reductions
  in visibility associated with blowing dust are possible along
  the I-70 corridor in eastern CO and western KS Friday
  afternoon and evening.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 415 AM MDT Thu May 2 2024

Overview: An upper level low centered invof the US/Canada
border (southern Saskatchewan, northern MT/ND) this morning will
slowly progress eastward into Manitoba (tonight).. then
northeastward into Ontario (Fri-Fri night).

Today-Tonight: Potent shortwave energy (rounding the base of
the aforementioned upper low) in WY at 08Z this morning will
lift ENE-NE into South Dakota (this afternoon) and Minnesota
(tonight). Modest synoptic subsidence and surface pressure rises
in the wake of the upper wave (manifesting as a ~1010-1015 mb
surface high building southward from Nebraska into northwest and
north-central KS) will yield a clearing trend and decreasing
wind.. with near average highs in the 60s.

Fri-Fri night: Shortwave energy presently moving ashore the PAC
NW will dig southeastward into southern Idaho (tonight) and
track eastward across southern Wyoming (Fri).. rounding the base
of the aforementioned upper low and broad upper trough over the
northern Rockies.. then lift northeastward across South Dakota
and Minnesota (Fri night). A low-level southerly return flow
regime will be re-established in the lee of the Colorado Front
Range during the day on Fri.. as the MSLP-H85 height gradient
re-orients and tightens in response to the development and
intensification of a lee cyclone in Colorado (aided by the
aforesaid shortwave energy /DPVA/ approaching from the west).
Guidance indicates that strengthening southerly flow will advect
seasonably rich moisture (4-9C 850 mb dewpoints) into northwest
Kansas -- beneath a pronounced/pristine elevated mixed layer
(8-9 C/km 700-500 mb lapse rates) -- yielding ~1500 J/kg
mlcape/mucape at peak heating. Guidance suggests that an
evaporatively-cooled airmass.. emanating from fairly widespread
precipitation assoc/w the upper wave in Wyoming and the NE
Panhandle.. will surge southeastward into northeast Colorado
(manifesting as an abruptly northerly wind shift and effective
cold frontal passage) during the mid-afternoon (~21Z). Simulated
reflectivity forecasts via recent runs of the HRRR and NAM NEST
indicate that convection will [1] rapidly develop along the
effective cold front in northeast CO and [2] evolve into a
forward propagating MCS that progresses E-SE through northwest
KS during the late afternoon and early evening. With the above
in mind, expect a potential for widespread damaging winds and,
quite possibly.. a progressive dust storm.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Issued at 217 AM MDT Thu May 2 2024

Saturday morning the area is under west-southwesterly flow aloft
with upper level ridging now centered over the Intermountain West
and the next low pressure system off the coast of the Pacific
Northwest. After a mostly dry day Saturday with high pressure moving
across, weak waves will then move through the flow in the Saturday
evening-Sunday timeframe and may trigger a few showers and
thunderstorms (~20-30% chance). Sunday afternoon-evening the upper
low progresses across the Great Basin. Breezy to windy conditions
are expected Sunday into Monday due to the tightening gradient
between high pressure moving off to the east and a developing low in
the lee of the Rockies. Current forecast calls for gusts to around
30-40 mph. Into the first part of the work week, winds of this
magnitude may create critical fire weather conditions, mainly
focused across west and southwest portions of the area where
relative humidity is forecast to drop into the 10-20% range. Also
expecting showers and thunderstorms for parts of the area on Monday.
Some uncertainty remains in position of the surface low which would
influence severe potential. If any part of the CWA would be favored
to see strong to severe storm potential, expecting it`d be
across the eastern 1/3 to 1/2 of the area where CAPE values to
around 1000-2000 J/kg coincide with better moisture and ample
shear. Current confidence is low as the latest guidance has
trended the surface low farther east, and the severe potential
for our CWA hinges on its timing/ placement. Will continue to
monitor as guidance comes in better alignment. SPC`s current Day
6 (Monday) 15% risk is east of the area, from southwest
NE/eastern half of KS/central OK.

Tuesday-Wednesday may again have potential for portions of the area
(mainly west and southwest) reaching near-critical to critical fire
weather conditions with RH forecast in the teens and winds gusting
25-35 Tuesday and to around 25 mph Wednesday.

For temperatures, highs are forecast generally in the 60s for
Saturday before undergoing a warming trend into the 70s to low 80s
by the start of the work week, ever so slightly cooler Wednesday-
Thursday. For low temperatures, expecting low-mid 40s Sunday
morning, into the upper 40s to middle 50s Monday morning, and
upper 30s to mid-upper 40s Tuesday, Wednesday, Thursday
mornings.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 530 AM MDT Thu May 2 2024

GLD: VFR conditions will rule through the TAF period. Scattered
to broken mid-level ceilings (~12,000 ft AGL) will give way to
clear skies by mid to late morning. NW winds at 12-17 knots will
increase to 20-30 knots within a few hours after sunrise.. at
the onset of diurnal heating/mixing.. decreasing to 15-20 knots
during the early afternoon. Winds will become light and
variable at/around sunset this evening and persist overnight..
shifting to the S at 12-17 knots around sunrise Fri morning, at
the end of the TAF period.

MCK: Lingering MVFR ceilings (~1,000 ft AGL) at 11Z are
anticipated to rapidly lift/scatter within an hour or two after
sunrise, by ~14Z. VFR conditions will rule through the remainder
of the TAF period. NW winds at 10-15 knots will increase to
20-30 knots within a few hours after sunrise.. at the onset of
diurnal heating/mixing.. and persist through early afternoon,
decreasing to 15-20 knots during the mid-late afternoon. Winds
will become light and variable at/around sunset this evening (as
high pressure in Nebraska builds southward over Kansas) and
persist overnight, shifting to the S at 10-15 knots at the end
of the TAF period.. around or shortly after sunrise Fri morning.

&&

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

&&

$$

SHORT TERM...Vincent
LONG TERM...CC
AVIATION...Vincent