276
FXUS63 KGLD 040925
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
325 AM MDT Sat May 4 2024

.KEY MESSAGES...

- Monday has a chance for high winds (mainly gusts above 60+
  mph), blowing dust, and severe storms. However, there is still
  a fair amount of uncertainty with the placement/timing of the
  system so all listed hazards currently have less than a 50%
  chance of occurrence.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 320 AM MDT Sat May 4 2024

Overview: A potent upper level low moving ashore the Pacific
Coast today will progress eastward across the Intermountain
West (tonight-Sunday) and 4-Corners (Sunday night).

Today-Tonight: Expect a continued clearing trend with sunny
skies by late morning and early afternoon -- in assoc/w
synoptic subsidence and surface pressure rises in the wake of
shortwave energy lifting northeastward through the Dakotas --
along with light winds and slightly below average temperatures.
Near average overnight lows will follow, tonight.

Sun-Sun night: A southerly return flow regime will ensue, on
Sunday, as the MSLP-H85 height gradient reorients and tightens
in response to renewed surface pressure falls in the lee of the
central Rockies -- via height falls /increasingly cyclonic flow
aloft/ attendant the aforementioned upper level low approaching
from the west. Expect strengthening (25-40 mph) southerly winds
and a warming trend.. with highs ranging from the upper 60s to
mid 70s, warmest in eastern Colorado. Low-level flow will back
to the SSE and further strengthen Sunday evening -- on the
eastern periphery of an intensifying lee cyclone in Colorado.
Forecast soundings indicate 40-50 knot SSE flow `off-the-deck`
within a shallow mixed layer in eastern CO and adjacent KS
border areas Sunday evening into Sunday night -- after sunset,
~02-03Z -- suggesting a potential for strong winds (30-45 mph G
55 mph), though.. confidence is low with regard to whether or
not mixing will be sufficient to transport said flow to the
surface / penetrate a near-surface nocturnal inversion.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 238 AM MDT Sat May 4 2024

For Monday, there are still a lot of potential hazards that are
unclear if they`ll happen as there is still a sizable spread in
500mb low track and surface low setups. Compared to prior
forecasts, there is more consensus on the upper trough swinging
more into the Northern Rockies and Plains. In this scenario, the
deeper part of the low pressure would be well north into the
Dakotas, Montana, or even Southern Canada. With it, the rest of
the lower pressure and potential front would swing through the
area during the day Monday and bring dry air across most of the
area. With this, the severe weather threat would be limited to
Highway 83 and east or maybe even completely out of the area.
The main hazard would be the potential for high winds (namely
gusts to 60mph+) as long as the upper low swings near the area.
Blowing dust across the area and critical fire weather
conditions south of I-70 would also be possible with the strong
winds and dry conditions (though the dust could be hampered by
recent moisture).

There are still some scenarios that keep the low closer to the
area with dryline closer to the Colorado border (instead of
Central KS/NE). While scenarios like this now have a 25% chance,
it is worth mentioning that this scenario would bring the same
threat for high winds, but the severe threat would be much
greater with all hazards possible. Critical fire weather would
be more limited to parts of Eastern Colorado and the dust threat
would likely decrease as we would have stratus which would
weaken low level lapse rates.

Tuesday, the upper trough is forecasted to spin over the
Northern Rockies and Plains which will keep the area in roughly
westerly flow aloft and relatively low pressure at the surface.
The main thing to watch will be for a potential smaller wave to
move around the larger low and generate lower pressure near the
area. That could strengthen the winds a bit and maybe wrap some
more precipitation into the area, though severe weather looks to
be unlikely at this time. A small disturbance could also
weaken/disrupt the height gradients which would lower the chance
for strong/high winds. Temperatures would likely be similar to
Monday in the 70`s. Critical fire weather conditions would be
possible again along and south of I-70 depending on how dry the
air gets during the afternoon.

The rest of the week looks to have troughing or laminar flow
above the area as a cut-off low is forecast to try and split off
from the main flow and shift off to the west coast. This would
likely give us average temperatures in the 60`s and 70`s with
daily chances for precipitation if smaller disturbances move
through the flow and across the area. Hazardous weather looks to
be unlikely for this time period except for the possibility of
lows dropping into the mid to low 30`s if enough cold air
advects into the area and little to no moisture returns.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 320 AM MDT Sat May 4 2024

VFR conditions will rule through the TAF period at both
terminals. NNW winds at 10-15 knots will weaken and become
variable early this afternoon.. as surface high pressure in
Nebraska extends southward over northwest Kansas. Winds will
shift to the SSE-SE and increase to 10-15 knots this evening
(GLD) and Sunday morning (MCK).. as high pressure shifts east of
the region and a surface trough develops in the lee of the
Rockies.

&&

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

&&

$$

SHORT TERM...Vincent
LONG TERM...KAK
AVIATION...Vincent