-- Discussion containing changed information from previous version are highlighted. --
202
FXUS63 KLBF 222319
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
619 PM CDT Wed May 22 2024

.KEY MESSAGES...

- A strong cool front will dive into the area Thursday and bring
  the threat for severe thunderstorms, locally heavy rain, and
  strong winds behind it late Thursday afternoon into Thursday
  night.

- Thunderstorms chances increase Saturday afternoon through
  Sunday during the Memorial Day holiday as temperatures range
  near to slightly below normal.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 322 PM CDT Wed May 22 2024

On Thursday, a positively tilted upper trough will move across
Montana and Wyoming. Surface low pressure will deepen ahead of
the upper trough to near 995mb, becoming positioned from central
South Dakota through the western Sandhills into eastern
Colorado. Increasing southerly winds ahead of this feature will
bring dewpoints into the mid 50s and SBCAPEs to 1500-2000 J/KG
as highs reach near 80, with near 85 far southwest. The focus
for thunderstorms to initiate will be along the advancing cold
front across the northwest Sandhills and also a distinct
dryline located near Ogallala through Benkelman soon after 20Z.
Ahead of the dryline, surface winds will tend to be more backed
to the southeast across southwest Nebraska. Aloft, H7 to H5
lapse rates will steepen to 8.5 to 9C/KM. The location favoring
discrete supercells will be near the dryline northward to the
intersection of the cold front and dryline, possibly over Keith
county. As surface convergence increases along the cold front
and dryline, scattered thunderstorms are expected to develop by
late afternoon within an environment supportive of organized
severe weather given a moderately unstable environment and deep
layer shear near 40kts. Coverage of thunderstorms is expected to
increase significantly east of Highway 83 where PoPs increase
to as high as 80-90%. The Storm Prediction Center (SPC) has a
Slight Risk (Level 2 of 5) for areas east of a Crookston through
Hayes Center line and an Enhanced Risk (Level 3 of 5) over
central Nebraska, east of a Eustis to Arnold and Brewster line.
Forecast soundings depict clockwise curving hodographs,
favorable for a brief tornado by early evening. Isolated very
large hail to 2 inches in diameter is also possible. As storms
congeal along the advancing cold front, a severe MCS is likely
to develop into central Nebraska during the evening hours. Large
hail and damaging wind gusts up to 80 mph may occur. With the
progressive nature of the frontal boundary, expect the main line
of storms to exit southeastern zones by 06Z. While not overly
significant, rainfall amounts up to 1.25" is possible near and
east of Ainsworth through Broken Bow. With recent rainfall, this
may present at least a localized flooding risk.

Winds behind the cold front may gust up to 35 mph Thursday
night, as 3 hr pressure rises reach up to 6 to 9mb. Lows fall to
the upper 30s to mid 40s, aided by winds keeping the surface
mixed.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 322 PM CDT Wed May 22 2024

On Friday, strong northwesterly winds will continue through
Friday morning with gusts up to 35 mph, lessening in the
afternoon. Weak cold air advection will keep afternoon highs on
the cooler side from near 65 to 70.

Saturday and beyond...active weather is expected Saturday
afternoon through Sunday. An upper trough over the Great Basin
will cross the region Saturday afternoon trough Sunday evening.
This will bring another good chance for showers and
thunderstorms. Highs range in the 70s Saturday and upper 60s to
low 70s Sunday. The main frontal boundary during this time will
be draped across southern and eastern Kansas during this time.
The severe weather risk remain uncertain at this time.

Northwest flow aloft Monday through Wednesday, with as slight
chance for showers and a few thunderstorms Monday across north
central Nebraska, then dry conditions Tuesday and Wednesday with
highs warming into the upper 70s to low 80s.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
-- Changed Discussion --
Issued at 620 PM CDT Wed May 22 2024

VFR conditions are expected to prevail through tomorrow evening
across western and north central Nebraska. The exception will be
late tomorrow afternoon, as scattered thunderstorm development
is expected near the HWY 83 corridor. Brief MVFR
ceiling/visibilities are possible inside thunderstorms along
with gusty, erratic winds. Confidence in timing and placement of
thunderstorms remain too low for inclusion at both KLBF and KVTN
for now, though this may be needed in future issuances.

Strong southerly LLWS is expected to develop overnight for all
area terminals, as a low level jet strengthens across western
Nebraska. Winds remain southerly through the valid period,
becoming gusty tonight and tomorrow, with gusts of 20 to 30kts
anticipated.
-- End Changed Discussion --

&&

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

&&

$$

SHORT TERM...Roberg
LONG TERM...Roberg
AVIATION...Brown