794
FXUS63 KLBF 300810
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
310 AM CDT Thu May 30 2024

.KEY MESSAGES...

- Strong to severe thunderstorms are possible late this afternoon
into the evening hours from southwestern into central and portions
of northeastern Nebraska.

- Strong to severe thunderstorms will be possible Saturday night and
Sunday night.

- Warmer temperatures are expected beyond Friday with highs in
  the 80s this weekend into early next week. Some readings may
  approach 90 Sunday and Tuesday.

&&

.SYNOPSIS...
Issued at 310 AM CDT Thu May 30 2024

H5 analysis from earlier this evening had a ridge of high
pressure which extended from eastern Nebraska, north into northern
portions of Manitoba Canada. West of this ridge, a strong shortwave
trough of low pressure extended from northern Alberta, south into
central Idaho. Immediately downstream of this feature, a lead
shortwave was positioned from the Black Hills, south into
northeastern Colorado. Other features of note this evening across
the CONUS, included a shortwave trough over the Arkansas Ozarks and
a deeper, more broad trough of low pressure, which extended from
Quebec, south into Virginia and the Carolinas. At the surface, high
pressure was anchored over northeastern Wisconsin. A stationary
frontal boundary extended from northwestern South Dakota into
northern Arkansas and northern portions of Mississippi and Alabama.
A surface trough of low pressure extended south from low pressure
located over western North Dakota. Immediately west of the surface
trough, a cold front extended from northeastern Wyoming into
northwestern Colorado and southwestern Utah. Showers and
thunderstorms, in association with an upper level disturbance were
exiting northeastern portions of the forecast area. Further west,
isolated showers were present from the northern Nebraska Panhandle
into northwestern portions of the forecast area. Skies were partly
to mostly cloudy overnight and 3 AM CT temperatures ranged from 59
degrees at Gordon to 67 degrees at O`Neill.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 310 AM CDT Thu May 30 2024

A rather complex precipitation scenario setting up for today
across the forecast area. Ongoing showers and thunderstorms
should exit the area by daybreak. Later this morning into the
afternoon hours, the before mentioned surface trough, will be
forced east by a northern stream trough of low pressure aloft.
By 21z this afternoon this boundary is expected to reside from
northeastern Nebraska to southwestern Nebraska. With surface
heating this afternoon, modest SB CAPES of 1500 to 2000 J/KG
will develop INVOF the boundary per the latest NAM12 soln. By
21z, this same model has little to no CIN present from central
into northeastern Nebraska, which will lead to thunderstorm
development late this afternoon. Further southwest into
southwestern Nebraska and northeastern Colorado, the cap will
hold on until this evening. That being said, precipitation
chances will begin this afternoon in the east, transitioning to
the southwest then west into the evening hours. As for the
severe threat, deep layer shear is on the order of 20 to 25 KTS
in the central and northeastern forecast area and lapse rates in
the H7-H5 layer would indicate only a meager threat for severe
storms this afternoon and evening. Believe the greater threat
for isolated severe storms will reside over southwestern
Nebraska, as mid level lapse rates are steeper and deep layer
shear stronger. However, given the degree of convective
inhibition this afternoon, storms should hold off in SW Nebraska
until the evening hours. As for highs today, they will range
from the lower 70s INVOF the surface trough (ie. more abundant
cloud cover) to the middle 70s elsewhere. On Friday, the front
will be forced south and southwest of the area into Kansas and
northeastern Colorado. Though the main threat for thunderstorms
will reside south and west of the forecast area, couldn`t rule
out a stray shower or thunderstorm Friday, thanks to easterly
winds and the presence of mid level warm air advection.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 310 AM CDT Thu May 30 2024

Thunderstorms are expected to be ongoing across northeastern
Colorado Friday evening. This activity may eventually make it
east into southwestern Nebraska overnight before dissipating.
Better chances for thunderstorms will arrive late Saturday into
Saturday night across the area. The mid level pattern will
become more zonal, leading to stronger mid and upper level winds
across the area. By Saturday afternoon, a nice theta-e ridge
will build north from northeastern Colorado into the Nebraska
Panhandle. With surface heating ie. temps in the lower to middle
80s, SB capes will reach 2000-2500 J/KG in the panhandle and
western Nebraska Saturday afternoon. Deep layer shear of 30+ KTS
and steep mid level lapse rates will support large hail and a
damaging wind threat, mainly over the western half of the
forecast area. A similar setup will commence on Sunday
afternoon, albeit, slightly farther east per the latest GFS
soln. With highs in the mid to upper 80s Sunday, and forecast
dew points in the lower to middle 50s west of highway 83 and 60+
dew points east of this route, CAPES may approach 3000+J/KG
Sunday afternoon. The latest GFS indicates deep layer shear of
30 to 40 KTS Sunday afternoon which should favor severe
thunderstorms. Beyond Sunday night, the threat for precipitation
will decrease across the area as stronger mid and upper level
winds, shift north into the northern Rockies and northern
plains. By midweek next week, the models are trending toward a
broad ridge of high pressure aloft building into the central and
southern Rockies.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1201 AM CDT Thu May 30 2024

Scattered -TSRA across southwest and north central Nebraska
will continue to move east overnight with no impacts to KLBF and
KVTN.

Otherwise, VFR conditions are expected at both KLBF and KVTN
until at least 12Z. Thereafter, ceilings will lower with MVFR
conditions expected at both sites through the early afternoon
with a return to low-end VFR conditions for remainder of the
period. Southerly winds will veer towards the north/northeast by
this afternoon.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SYNOPSIS...Buttler
SHORT TERM...Buttler
LONG TERM...Buttler
AVIATION...Viken