068
FXUS63 KGLD 021709
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
1109 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 SATURDAY 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 /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1107 AM MDT Thu May 2 2024

VFR expected to prevail at both KGLD and KMCK through the TAF
period. Northwest surface winds will gust up to 25 kts through
this afternoon, diminishing tonight, then increase again Friday
morning from the southeast and gust up to 30 kts.

&&

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

&&

$$

SHORT TERM...BV
LONG TERM...CC
AVIATION...024