433
FXUS63 KLBF 030601
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
101 AM CDT Thu Jul 3 2025

.KEY MESSAGES...

- Dry conditions persist through the daytime Thursday with above normal
  temperatures likely as highs climb into the middle to upper
  90s.

- Rain and thunderstorm chances return as early as Thursday
  night (~30%) but peak during the afternoon and evening on
  Independence Day (40-60%).

- Periodic rain and thunderstorm chances continue into next week
  with generally 30-50% probabilities each day Sunday through
  Wednesday.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 338 PM CDT Wed Jul 2 2025

Amplified upper-level ridging remains in place across the central
and southern Rockies. Broad troughing across the Great Lakes was
slowly settling east while modest shortwave troughing was situated
over southern California. Locally, the area was situated downstream
of the ridge axis with general northwesterly flow overhead.

Tonight, expect ridging to shift east onto the High Plains.
Southerly flow will continue across the area though moisture
advection appears poor today with a region of dry air situated
immediately upstream across western Kansas. At the surface, a wind
shift line was in the vicinity of the Nebraska/South Dakota border.
Some weak convergence in this area and within the easterly flow
running into the Black Hills north of this feature was leading to an
area of cumulus gradually shifting east-southwest following the mean
mid-level flow. While a few echoes have appeared on KLNX radar, the
shallow nature of the clouds in addition to bases nearing 12-15kft
AGL will preclude any threat for lightning or precipitation. Highs
continue to climb steadily this afternoon and believe values should
top out in the upper 80s to lower 90s. Lows tonight should remain on
the milder side. This is due to limited boundary layer decoupling as
a modest LLJ develops. Utilized the NBM for MinT values which
closely aligned with short-term guidance producing low 60s to near
70F for Thursday morning values.

Thursday...ridge breakdown begins on Thursday as weak troughing
phases back into the flow and begins to lift north and east. In
response to this, southerly flow will strengthen as a low pressure
center deepens over northeast Wyoming/southeast Montana.
Temperatures will climb as a result and have boosted afternoon highs
as a result. The result is widespread 90s with a few locations
across our northern zones (generally Highway 20 and north) climbing
into the upper 90s. It`s interesting to note that probabilities of
exceeding 90F are generally 80% or greater for the whole of the area
but probabilities of exceeding 100F are 5% or less for anywhere in
the area. This suggests confidence is fairly high that the forecast
values likely resemble the more significant values from the ensemble
envelope and, as a result, are unlikely to be conservative.
Populating dew points from the model blend produced upper 50s to
upper 60s with the muggier conditions expected east of Highway 183.
Believe heat index values will climb into the upper 90s and approach
the triple digits for these areas, but should remain below Advisory
criteria (100F or greater). An elongated surface trough extending
south from the surface low to the north will move in from the west
late in the day. This will likely be the focus for increasing rain
and thunderstorm chances late. While the inherited PoPs near 20-30%
across our west, various deterministic solutions are less bullish
and maintain dry conditions for most if not all locations. Even
short-term ensemble guidance such as the HREF only introduces ~10%
probabilities of seeing > 0.01" QPF for any period of time Thursday
evening. Will monitor trends and adjust forecast PoPs as necessary
with subsequent forecasts.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 338 PM CDT Wed Jul 2 2025

Independence Day...a more active 4th of July holiday appears on tap
for much of western and central Nebraska. As the surface trough
continues to shift east, an increasing LLJ across the warm sector
should support improving moisture quality ahead of it. Eventually, a
shortwave trough will cross the central Rockies and interact with
the wind shift line. This should allow for scattered rain and
thunderstorms early but more expansive rain and thunderstorm
coverage later in the day near and east of Highway 83. Antecedent
conditions will support the threat for heavy rain...increasing
moisture quality to the tune of 1.50"+ PWATs or roughly 150-200% of
normal, saturated profiles with skinny CAPE from LFC up through the
EL, deep warm cloud layers, and limited storm venting with anvil-
level storm relative winds remaining fairly weak at or below 15
knots. What may limit the threat for any magnitude of flooding
somewhat will be progressive storm motions and the lack of any
stationary boundary for storms to train along. Even so, EPS/GEFS
probabilities for exceeding 0.50" climb to around 40-50% for
Friday/Friday night. Respective 90th Percentile output for QPF
suggests fairly expansive 0.75"+ across our eastern zones with 0.25"
or greater for the remainder of the forecast area. SPC also
introduced a Marginal Risk (level 1 of 5) across our far north
central Nebraska counties. This likely is the result of increasing
shear along the surface trough late in the day. Convection appears
likely to rip along this line northeast to southwest and perhaps
could extend as far south as north central Nebraska. Generally am in
agreement with SPC on this decision and emphasize confidence is
limited and this is portrayed by the level 1 of 5 designation.

Saturday and beyond...in the wake of the departing system, cooler
temperatures are likely for Saturday. This cooldown will be brief,
however, as ridging again builds across the Desert Southwest. While
deterministic solutions vary on magnitude of building high pressure,
ensemble probabilities suggest h5 heights exceeding 588 dam are
probable. The result is moderating temperatures with highs returning
to the upper 80s and lower 90s early next week. Rain and
thunderstorm chances continue as moist upslope flow should allow for
storms to form off the Front Range and settle downslope within the
broad westerly flow. Pattern recognition suggests severe weather
will be in play each day, however, day-to-day predictability remains
low confidence as mesoscale features that could enhance/hamper the
setup are unresolvable at this range. PoPs for this timeframe
generally reach the 30-50% range each day but this could change for
the reasons mentioned above in the days ahead.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 102 AM CDT Thu Jul 3 2025

Skies will remain mostly clear over the next 24 hours with a few
high clouds possible around 25000 FT AGL. Winds will be gusty on
Thursday during the afternoon into the early evening hours with
gusts approaching 20 to 25 KTS.

&&

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

&&

$$

SHORT TERM...NMJ
LONG TERM...NMJ
AVIATION...Buttler