131
FXUS63 KGLD 280157
AFDGLD

Area Forecast Discussion
National Weather Service Goodland KS
757 PM MDT Thu Jun 27 2024

.KEY MESSAGES...

- Scattered thunderstorms may develop over portions of the area
  late Friday afternoon and evening. A few severe storms are
  possible. At this time, brief/localized instances of damaging
  wind appear to be the primary hazard.

- Daily potential for afternoon/evening storms this weekend into
  next week.

- Heat index values in the low triple digits Monday.

&&

.UPDATE...
Issued at 735 PM MDT Thu Jun 27 2024

As of 0135 UTC (735 pm MDT).. radar/observational trends and
simulated reflectivity forecasts via the 00Z HRRR suggest
little, if any, potential for convective development through
the duration of the evening. High based convection presently
developing along/east of the I-25 corridor (mainly south of
Denver) will track east toward the CO-KS border late this
evening. While brief, localized wind gusts up to 65 mph cannot
be ruled out with any high-based showers/virga (by virtue of
moderate to strong DCAPE, ~1200-1800 J/kg).. substantial
intensification of said activity is presently not anticipated.
With the above in mind, Severe Thunderstorm Watch 475
(previously in effect until 03Z UTC) has been canceled.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 315 PM MDT Thu Jun 27 2024

Across the Tri State region this afternoon, skies are a partly
cloudy to mostly cloudy mix. Scattered showers are occurring around
the area. Breaks in the cloud cover through the day has allowed for
temps as of 200 PM MDT to range in the upper 80s to mid 90s. With a
meandering surface trough over the Highway 27 corridor, winds ahead
of this are south-southwesterly with gusts up to 30 mph at times.
Along/west of this west-northwest flow is in place.

The main wx threats for the short term period will be the chances
for strong to severe storms each day, with the focus for late
afternoon/evening development.

As mentioned, there is currently a surface low/trough that has just
moved east of the Colorado border. There is a front attached to this
that stretches south into southwest Kansas. Aloft, the RAP40 500mb
analysis is showing a shortwave over southeast Colorado that will
lift into Kansas and interact with the surface features this
afternoon and tonight. From the latest CAMs(HRRR, RAP and NamNest)
the latest HRRR is the most probable at this time showing convection
starting along the trough.

With convection already cropping up around/in the CWA, SPC has
issued a Severe Thunderstorm Watch to cover expected convection
through 03z Friday. All threats on the table with decent instability
and high PW values, especially ahead of the boundary/trough. Winds
around 60 mph, hail 1-2 inches w/ parameters suggesting a tornado or
even landspout possible along the boundary. The HRRR does show this
activity pushing east by 03z-04z Friday with scattered convection
thereafter.

Going into Friday, similar situation to today. High pressure is
slowly settling east of region through Friday night. Looking at a
N/NE flow into the area through the period. A trough moves off the
Front Range as a front, settling south of the area by 12z Saturday.
It will be this front interacting with a another shortwave to
trigger another round storms. Afternoon and evening setup for these.
SPC still favors a Slight Risk for severe storms for much of the CWA
with hail and wind threats once again. PW values do shift east
through the period, but at least 0.80" in the west, up to 1-1.20"
east, so some heavy threat is possible.

For Saturday, slightly cooler air will be present over much of the
area through the day. The focus for strong to severe storms will be
along/south of Hwy 40 closest to the previous front that remains
over southern KS through the day. SPC carries a Marginal Risk for
severe storm potential there with wind and hail threats. There will
be chances north of Hwy 40, but a better stable airmass resides
lowering the severe threat.

For temps, highs on Friday will be ranging in upper 80s into the mid
90s. Going into Saturday, a range of 80s is expected with warmest
locales along/south of I-70. Lows tonight will range mainly in the
60s, with areas east of Highway 83 around 70F. For Friday night,
upper 50s west to the upper 60s east will give way to upper 50s to
lower 60s for Saturday night.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 1223 PM MDT Thu Jun 27 2024

From the latest runs of the GFS and ECMWF, amplified 500mb ridge
will persist over the central Plains for Sunday and Monday, before
the ridge flattens to zonal flow and shifts slightly eastward from
Tuesday onward. There will be several shortwaves that traverse the
northern periphery of the ridge each day.

At the surface, the focus will be on a couple lows and their
associated fronts that move through the region. The first system
starts off a trough over the eastern slopes of the Rockies on
Sunday, with a very slow shift south and east into Monday, settling
south of the CWA for the Tue-Wed timeframe. A quicker system for the
end of the week will push through the area, aided by a digging ridge
from the north.

As a result, each day the passage of the aforementioned shortwaves
will interact the surface front/low, creating rw/trw. For Sun-Mon,
while some initiation is expected for the late afternoon hours each
day, the best chances(30-40%) will occur during the evening,
especially north of the Interstate. These areas will be closest to
the system as it slowly moves into the CWA. Better moisture feed and
instability is expected for Tue-Wed as the boundary sets up
along/south of the area, opening the area up to more of an easterly
fetch for better low level moisture/instability and thus better
storms chances(40-60%). High PW values around 1-2" are expected each
day, with high numbers in the east, combined with daytime heating,
will create as least the chances for storms producing heavy
rainfall. But strong to severe storms are possible as well.

For Thu-Fri, this will envelope the arrival of the second boundary
albeit a bit weak. There still be be chances for storms like
mentioned above, but lower chances of coverage area-wide(30-40%).

For temps, daytime highs each period will continue at above normal
levels. On Sunday, 80s area-wide. 90s will persist each day next
week except for Monday where a range from the mid 90s to lower 100s
are expected. Hottest areas will be along and east of Highway 25.
With a return to 100+ degree heat, heat indices will be around 100
in areas along/east of Highway 83. This will have to be watched for
a potential Heat Advisory. Overnight lows will range in the 60s. A
few spots east on Monday night could only drop to the 70F mark.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 530 PM MDT Thu Jun 27 2024

VFR conditions will rule through the TAF period. 10-20 knot
S-SSE winds are anticipated to become light and variable
overnight. Winds will shift to the N and increase to ~15 knots
within a few hours after sunrise (~13-14Z).. becoming light and
variable once again during the early-mid afternoon. While a
thunderstorm cannot be ruled out at either terminal this
evening (and again on Friday).. confidence in thunderstorm
development, location and coverage is low enough to preclude
explicit mention at this time.

&&

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

&&

$$

UPDATE...Vincent
SHORT TERM...JN
LONG TERM...JN
AVIATION...Vincent