546
FXUS63 KLBF 160543
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1243 AM CDT Tue Jul 16 2024

.KEY MESSAGES...

- Scattered severe storms are possible across parts of wrn and
  ncntl Nebraska tonight and again Tuesday afternoon and
  evening. The main hazard tonight is damaging wind gusts. The
  risks of tornadoes or large hail tonight tonight is low but
  not zero. All severe weather hazards are possible Tuesday.

- Isolated severe storms are possible across western Nebraska
  Wednesday. The primary hazard at this time is wind damage.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 345 PM CDT Mon Jul 15 2024

An upper level disturbance across swrn WY this afternoon will move
east and set off scattered thunderstorms across the Laramie and Colo
Front ranges around 21z-22z this afternoon. These storms will move
east into wrn Nebraska with modest upscale growth occurring before
weakening along and east of highway 83 by 03z-06z this evening.
Satellite and radar are also detecting a second round of storms
firing further west across WY. These storms could reach wrn Nebraska
in a weakened state around 04z this evening.

The HRRR has been fairly consistent suggesting isolated to low-end
scattered 60+ mph wind gusts across wrn Nebraska this evening. The
model has also been hinting at a severe storm firing across the srn
Black Hills which will move southeast an merge with the ongoing QLCS
across the cntl Sandhills.

Other than easterly upslope moisture convergence across wrn Nebraska
and on the Laramie range this afternoon, there is very little sfc
focus for storm development and the warm air advection is way far
south across swrn KS where a sfc cold front will lie. PWAT is low-
end at 1.00-1.25 inches but predicted to pool to 1.25-1.50 inches.
Winds below 700mb are very weak, less than 10 kts and SPC has
suggested less than 2 percent tornado potential. This system appears
to have only two things going for it. It has excellent moisture at
500-300mb and winds at that level are 30-50kts.

The next severe weather chance arrives Tuesday afternoon across
ncntl Nebraska. The models have been advertising storm development
in this area for a few model runs now. A reinforcing cold front will
be moving south through ern SD during the afternoon. Meanwhile, a
weak meso-high forms in the wake of tonight`s storms providing
moisture return into ncntl Nebraska Tuesday afternoon. Winds aloft
at h500-300mb will remain strong at 40-50kts and winds below 700mb
are a bit stronger 10-20kts. For this event, SPC is suggesting all
storm modes will be possible with storm initiation possible by 19z-
20z according to the CAMs. Storm development will be directed south
and southwest following a theta-e ridge across swrn and scntl
Nebraska. PWAT in the RAP model is 1.25-1.50 inches and the cap is
weak with h700mb temperatures 12C or less which would support a
large hail threat.

Temperatures across swrn Nebraska peaked early this afternoon with
the passage of cold front and then began to fall or remain steady.
Dew points will remain in the upper 50s to lower 60s behind the
front and the risk of 100 degree heat indices is low. The latest
temperature and dew point forecast using the short term model blend
and the NBM 50th percentile suggests heat indices in the low to mid
90s the rest of the afternoon. The Heat Advisory in effect across
swrn Nebraska this evening has been cancelled for this reason.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Issued at 345 PM CDT Mon Jul 15 2024

In the wake of the storm activity Tuesday, much cooler drier air
will move into wrn/ncntl Wednesday. Still, moist upslope return
flow and winds aloft of 30-40kts across wrn Nebraska is the
basis for a marginal severe weather risk west of highway 61. It
is worth noting the NAM shows little or no storm development but
the FV3 is lighting up the Nebraska Panhandle by 00z Wednesday
afternoon. One reason for this might be the NAM shows dew points
around 50F but the FV3 indicates upper 50s dew points; much
more unstable.

There is one more significant rain chance and that is associated
with a nrn stream upper level disturbance off the coast of nrn CA/OR
this afternoon. This disturbance will track north around the
amplified h500mb ridge across the wrn U.S. and then dive south
through the nrn high Plains. Later forecasts will analyze the severe
weather potential for this system.

Otherwise, comfortable weather is predicted Wednesday through Monday
with highs mostly in the 80s. Friday will be the warm day. A period
of warm air advection across wrn Nebraska will likely lead to highs
in the lower 90s in some areas.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1243 AM CDT Tue Jul 16 2024

An area of showers and thunderstorms is expected to impact the KLBF,
and to a lesser degree, the KVTN terminal through 09z overnight.
Visibilities may fall off to around 5 miles at the KLBF terminal
with some gusty winds up to 35 KTS. Overnight, expect gradual
clearing with scattered ceilings of 20000 to 25000 FT  expected by
sunrise Tuesday. Another round of showers and storms may impact
portions of the forecast area late Tuesday afternoon into early
Tuesday evening. At this time, the main impact is to the KLBF
terminal from 22z Tuesday through 02z Wednesday. Visibilities may
fall off to around 4 SM with broken ceilings of 6000 FT expected.
Look for thunderstorm timing at the KLBF terminal to be better
defined with the 12z and 18z forecasts later today. By late evening
tuesday, expect high cloudiness at the KLBF terminal. At the KVTN
terminal, some low level cloudiness may move into the area by late
evening with ceilings around 4000 FT AGL.

&&

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

&&

$$

SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Richie