364
FXUS63 KLBF 160512
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1212 AM CDT Mon Sep 16 2024

.KEY MESSAGES...

- Potential for thunderstorms with strong gusty winds and an
  isolated storm with large hail mainly along and west of Hwy 61
  this evening thorugh early tonight.

- Confidence continues to increase for the potential of gusty
  winds at or above 30mph Monday and Tuesday.

- A cold front will bring potential for strong to severe
  thunderstorms late Tuesday into Tuesday night, along with
  locally heavy rainfall, mainly west of Hwy 83.

- Low confidence in potential impacts from a storm system across
  central and western Nebraska next weekend.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 410 PM CDT Sun Sep 15 2024

As has been the case, central and western Nebraska remains
capped with a good deal of elevated instability in place.
However short wave energy rotating around a closed low diving
into CA will help nudge a dry line off to our west into the
region and provide a trigger for thunderstorms. Radar already
shows an initial batch of convection starting to fire across
northeast Colorado. Confidence in timing convection is not high
as early radar trends are outpacing initial expectation for
initiation later this evening so will be monitoring radar trends
very closely. The dry line does not make much progress eastward
this evening so anticipate the main threat for severe storms
will generally be from Hwy 61 westward. Storms will then
continue moving eastward overnight and guidance is showing a
pronounced resurgence early Monday morning out near Hwy 281 as
the axis of the low level jet shifts eastward before diminishing
later Monday morning. The remainder of Monday looks to be warm,
dry, and breezy as low level winds edge up into the 90th
percentile and EFI/SoT guidance starts to amplify a signal for
gusty winds. There may be some showers/storms fighting the cap
again late in the day tomorrow mainly south of Hwy 2 that will
have to be watched through severe potential currently appears
low. Conditions remain breezy Monday night with the low level
jet again keeping some showers/storms around east of Hwy 83.

The potential for strong gusty winds will increase on Tuesday
as low level winds reach the 99th percentile ahead of a cold
front approaching from the west and the EFI/SoT signal becomes
stronger. Temperatures rising to around 90 degrees will help
build instability under the cop ahead of the front and
precipitable water values will increase to near the 99th
percentile as deep layer moisture transport increases in the
robust southerly flow. By Tuesday evening the cold front will
start pushing in from the west with thunderstorms and a threat
for damaging winds, large hail, and locally heavy rainfall.
Anticipate these threats will accompany the storms as they move
eastward at least to around the Hwy 83 corridor into Tuesday
night, then continue across the region into eastern Nebraska by
Wednesday morning. Will have to watch for any upward trend in
evolution of this system closely since it is very dynamic with
potential for upscale development.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 410 PM CDT Sun Sep 15 2024

Ensemble guidance largely remains consistent and in good agreement with
little change from previous solutions regarding progression of upper
level features, depicting a rather blocky flow regime dominated by
split flow over the eastern US with a large northern stream ridge
undercut by the lingering remnant of Francine with a closed low over
the southeast. This will continue to force the closed low to our west
northward through the Rockies and into Canada as it fills through
Wednesday. Another deep low will quickly follow as it moves from the
west coast on Wednesday into the southern Rockies through the end of
the week. The airmass will briefly dry out behind the frontal passage
late Tuesday into Wednesday, though with continued deep southerly flow
ahead of the next low precipitable water values will rise again into
the 90th percentile by the end of the week.

Solutions then start to diverge with potential for split flow across
the Plains as a vigorous short wave may break from the main trof and
close off as it moves by just to our south this weekend. If the upper
low does close off a surface low will slowly move by just to our south
this weekend with Nebraska in the FGEN/deformation zone in the
northwest quadrant of the low with potential for a prolonged period of
precipitation through the weekend. EFI/SoT guidance has a QPF signal
which supports the potential for locally heavy rainfall, though any
severe threat is uncertain. If the upper trof remains more as a
progressive open wave we may see a weaker, faster system earlier
in the weekend with the best potential for significant
precipitation remaining off to our south and east. Blended
ensemble guidance spreads the uncertainty out across the period
showing at the very least unsettled conditions with potential
for showers and thunderstorms through the latter portion of the
workweek and into the weekend. Will see if an upward trend for
precipitation next weekend develops in guidance over the next
several days. There is higher confidence in the temperature
regime with temperatures at or above normal through the latter
portion of next week, becoming cooler with readings below normal
behind our weekend system.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 1212 AM CDT Mon Sep 16 2024

There will be a limited threat for isolated thunderstorms into
the overnight hours mainly over northern and northwestern
Nebraska. There is a minor threat for thunderstorms in the
vicinity of the KVTN terminal through 10z overnight. Otherwise,
expect scattered high clouds to persist into the morning hours
on Monday. There is a secondary threat for thunderstorms Monday
evening, however at this time, the main threat is expected to be
off to the east of the KLBF and KVTN terminals. With low
forecast confidence in any storms impacting the terminals Monday
evening, will forgo mention in the 06z TAF forecasts. Winds
will be gusty from the south on Monday into Monday evening with
gusts reaching around 30 KTS for both terminals.

&&

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

&&

$$

SHORT TERM...MBS
LONG TERM...MBS
AVIATION...Buttler