217
FXUS63 KLBF 061757
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1257 PM CDT Sat Jul 6 2024

.KEY MESSAGES...

- Scattered severe storms are possible across wrn and ncntl
  Nebraska this afternoon. The hazards are large or very large
  hail and wind damage. Confidence for storm development is
  medium.

- The risk of severe weather Sunday through Friday is low.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 343 AM CDT Sat Jul 6 2024

An upper level low circulating across the nrn Plains this
morning will move east into the Dakotas this afternoon. A surge
of strong 30-50kt h500-300mb winds on the south side of the low
will push into Nebraska and trigger a round of strong to severe
storms by early to mid afternoon. The focus is a weak frontal
boundary positioned across the cntl Sandhills and ncntl
Nebraska. The best guess on timing of storm development
according to the HREF and CAMs is 18z with storm activity moving
east and southeast out of the area by 00z. Additional strong to
severe storms are possible farther south during the afternoon,
along and east of highway 83 where a cold front will be moving
through.

Local studies suggest the potential for significant hail as
suggested by the SPC outlook. Cold air aloft, -13C at h500mb, strong
deep layer shear near 50kts and steep lapse rates 7+ C/km at h850-
500mb support the potential for very large hail. The HRRR also shows
60+ mph gusts developing as the storm activity grows upscale across
cntl Nebraska. The tornado threat remains low and the reason for
this is weak winds below 700mb, generally less than 20kts. There
will be a brief window of stronger low level winds at the onset of
storm development. Otherwise, hodographs are fairly linear
supporting storm splitting and upscale growth as the system moves
eastward.

The next rain chance develops Saturday night and Sunday with the
approach of a second UA disturbance moving through srn British
Columbia this morning. This rain chance is mainly diurnally driven
favoring Sunday afternoon for the best chance. The atmosphere will
be cool and moist, 2-5C at h700mb with h850-300mb RH 60-80 percent.
This rain will also be post frontal and the risk of severe weather
is low.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 343 AM CDT Sat Jul 6 2024

An upper level trof of cold air will be passing through Nebraska
Monday. Cool moist air will remain across wrn/ncntl Nebraska as
this happens and the NAM soundings would seem to support
diurnally driven showers and thunderstorms but there is no upper
level support shown in the model. The forecast is dry. The
models show a second trof dropping through Nebraska Wednesday
and the ECM suggests an isolated rain chance. NBM POPs are very
spartan for this event and later forecasts may increase rain
chances to slight or low-end chance.

Once this trof moves east, heights will gradually rise in response
to an upper level ridge across the wrn U.S. building east. Dry
and warmer weather is likely across wrn/ncntl Nebraska Thursday
through Saturday. The focus for rain appears to be farther
north across the upper Midwest during this time.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1256 PM CDT Sat Jul 6 2024

Isolated thunderstorms will become more scattered and numerous
throughout the afternoon. Some storms may become severe with large
hail, strong and erratic winds, and an isolated tornado as the main
threats. Main area of development will be across southwest and
central Nebraska, impacting KLBF during the late afternoon hours.
Thunderstorms will push off to the east by 00Z with overcast skies
continuing through Sunday morning. Across the north (KVTN),
thunderstorms should remain south of the terminal with just some
brief lowering of clouds expected. Improvement in ceilings returns
Sunday morning.

&&

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

&&

$$

SHORT TERM...CDC
LONG TERM...CDC
AVIATION...Kulik