712
FXUS63 KLBF 041133
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
633 AM CDT Sat May 4 2024

.KEY MESSAGES...

- An all hazards severe weather event is possible Monday
  afternoon, generally affecting areas along and east of
  highway 83.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 341 AM CDT Sat May 4 2024

Drier air and clearing skies have swept into wrn and ncntl Nebraska
this morning. A check on afternoon cumulus clouds was generally
negative. The models show warmer air moving in aloft off-setting
saturation 850-700mb. 300-850mb RH will fall to around 20 percent
today which would support full sun conditions with just scattered
cumulus.

Sfc high pressure across the cntl/nrn Plains today will move east
into the Midwest tonight setting up south winds and return moisture
across wrn/ncntl Nebraska. The models suggest the potential for
morning stratus across wrn Nebraska Sunday which could linger into
the afternoon as the moisture deepens.

The forecast today through Sunday concerns temperatures and the
forecast leans toward the warmer NBM 50th guidance. A blend of the
short term model blend and the RAP model is in place for highs in
the 60s today, 30s to around 40 tonight and then a modest warm up
Sunday into the 60s to near 70.

A check on the 500m AGL winds Sunday suggested sustained speeds of
25 to 30 mph across wrn Nebraska. Deep cyclogenesis will be underway
across the nrn high Plains. The RAP model suggested gusts of 30 to
40 mph across wrn Nebraska. The wind forecast using the short term
model blend and the NBM 50th came in a bit stronger with gusts of 35
to 45 mph. Given the caliber of the incoming weather system,
potentially record sfc low pressure- sub-980mb across nrn ND and srn
Saskatchewan Monday night according to the NAEFS, the stronger wind
forecast would appear warranted.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 341 AM CDT Sat May 4 2024

Moisture return will deepen Sunday night with strong south winds
of 40-50kts at h850-800mb. The NAM reflectivity product, the
NAM soundings and the RAP model suggest saturation reaching to
800mb which would support drizzle or light showers. POPs for
this feature have been limited to 50 percent but it is worth
noting the h850- 700mb theta e advection will be running strong
across far eastern WY and the Nebraska Panhandle. There is the
potential for an isolated storm or two to fire off the Laramie
range, Cheyenne divide or Pine Ridge late Sunday afternoon which
could drift into wrn Nebraska Sunday evening. Otherwise, strong
capping at h700mb should limit rain chances to just showers or
drizzle.

Attention is drawn to the prospect of an all hazards severe weather
event Monday afternoon generally affecting areas along and east of
highway 83. The upper level forcing in the form of height falls and
an approaching PV1.5 anomaly appear to be quite strong and could
start storm activity as early as 18z-19z Monday afternoon. The focus
will be strong south winds and theta e advection ahead of a Pacific
cold front which should be advancing through wrn Nebraska Monday
morning. Still unknown is the northward extent of the warm sector
opening up across KS into Nebraska.

The warm air advection for this event appears to be aimed at cntl
Nebraska and the day 3 SPC svr wx outlook favors cntl and ern
Nebraska for this and other reasons.

Sub 985mb sfc low  pressure will stall and slowly fill across the
nrn Plains Monday night and Tuesday. The occlusion process will
cause the sfc low to reform across the Great Lakes Wednesday. The
models appear to be maintaining the high wind risk mostly across MT
and the Dakotas Monday and Tuesday. The Pacific front Monday could
potentially spread high winds out of WY and into wrn Nebraska.

Otherwise, The early week storm will form a large upper low across
the nrn U.S. which will slowly weaken throughout the week. Subzero
h700mb temperatures will persist across wrn/ncntl Nebraska
throughout the week. The cold air aloft and strong daytime heating
would support afternoon showers and thunderstorms. The NBM suggested
daily rain chances, mainly across nrn Nebraska.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 632 AM CDT Sat May 4 2024

VFR conditions with clear skies are expected to prevail today
and tonight across western and north central Nebraska. Winds
will be light north today, switching to southeast tonight.

&&

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

&&

$$

SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Taylor