319
FXUS63 KLBF 041143
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
643 AM CDT Sat Oct 4 2025

.KEY MESSAGES...

- Critical fire weather conditions are expected Saturday with
  Red Flag Warnings for much of west central Nebraska as a
  result.

- A Marginal Risk (level 1 of 5) for severe weather remains in
  place across western Nebraska late Saturday afternoon and
  evening with damaging winds the main concern.

- Much cooler temperatures will bring more Fall-like conditions
  for Sunday and Monday before temperatures slowly recover to
  near-normal by mid-week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 402 AM CDT Sat Oct 4 2025

Active weather expected across much of the region today in advance
of and behind a strong cool front.

Early this morning, breezy south winds were observed across western
and central Nebraska. This was in response to a strong LLJ
overspreading the area as h85 heights tighten. Local VWPs (KLNX,
KUEX, KGLD) all show 25-35 knot flow around 100m AGL and these
magnitudes should increase through daybreak with a slight shift
east. To the north, the frontal boundary was already moving into
southwest South Dakota and will continue to shuffle south slowly
through the afternoon before stalling across the central Panhandle
through central South Dakota. Southerly flow will persist into this
feature and with h85 flow strengthening to 30 to 40 knots, expecting
strong kinematics to stir up low-level mixing. This will boost
daytime highs into the upper 80s to lower 90s once again. The
difference between today and Friday is increasing mid-level dry air
which should effectively mix down to the surface. This will promote
a localized area of afternoon humidity minimums falling to around 20
percent (+/- 2%). Forecast soundings show deep mixing, potentially
as high as 3km AGL. With strong unidirectional flow within the
boundary layer, winds will be strong and persistent with gusts up to
45 mph. Further east, where moisture is greater, mixing may be a
little more limited and this may limit the strongest winds from the
low-level speed max from reaching the surface. This will need
monitored closely as 50+ knot flow resides around 1-2 km up and
should mixing tap into these stronger winds, gusts may potentially
approach 60 mph (High Wind Warning criteria). This threat extends
then to southwest Nebraska as the LLJ strengthens once again. NBM
probabilities for exceeding 48 knots once again remain around 50-75%
but do not encompass a large spatial coverage. Therefore, will forgo
Wind Headlines but folks should be wary of strong crosswinds on east-
west routes.

Regarding thunderstorm potential...as the cool front settles south,
moisture increases from a Pacific airmass in its wake. Forcing aloft
increases as the main h5 trough lifts north and east across the
Front Range. While temperatures remain warm through late afternoon
and evening, lapse rates are fairly limited and with the deep
boundary layer, instability will be poor. HREF mean MUCAPE values
remain at or below 500 j/kg. Though deep layer shear is strong, this
limited instability will likely limit the overall scope of
thunderstorm threats. The Storm Prediction Center (SPC) maintains a
Marginal Risk (level 1 of 5) with a slight eastward shift towards a
North Platte to Ainsworth line and points west. Again, the
background environment...deeply mixed boundary layer, strong flow
aloft, poor instability...suggests more of a damaging wind threat
than severe hail threat. Earlier runs of the HRRR which suggested
isolated cells early has backed off on this thought with scattered
to widespread convection nearly from the start. Rainfall potential
has also increased, likely due to richer boundary layer moisture
behind the front and increased storm coverage/duration into the
evening. The going forecast now paints 0.15" or greater total QPF
for the western Sandhills and amounts around 0.50" for far western
Cherry/northeast Sheridan Counties. PoPs should quickly decrease
after Midnight as the trough axis lifts north and east and the
surface front settles south and east of the area. Cooler air will
quickly infiltrate the area with lows returning to the 40s west of
Highway 83 and lower 50s to lower 60s to the east.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 402 AM CDT Sat Oct 4 2025

Sunday and Monday...much cooler temperatures are expected as modest
Canadian high pressure noses in from the northwest. Elongated
troughing will extend from the central valley of California up
through the Northern Plains but overall northwesterly flow will
persist. Highs fall into the 60s and 70s for Sunday, decreasing
further to the 50s for Monday. Precipitation chances return early
Monday as the frontal boundary from Saturday stalls south across
Kansas and easterly upslope flow allows for scattered showers and a
few weak thunderstorms to percolate. No severe weather is expected
and as central high pressure passes to the east, the orographic lift
will subside and dry conditions will return for much of the daytime.

Tuesday and beyond...temperatures will slowly climb towards the
middle of the week as ridging builds along the Gulf Coast. A few
weak disturbance will round the upper-level high pressure and may
present a few limited chances for precipitation but PoPs inherited
from the model blend remain limited to Slight Chance (< 25%) owing
to low confidence. Similarly, precise temperatures remain somewhat
in question as NBM inner-quartile spreads approach 10F for the
latter half of the week. This is largely due to notable
discrepancies between deterministic and ensemble guidance. For now,
inherited temperatures hug the cooler end of the forecast envelope
but pattern recognition suggests these values will likely climb
slightly in the coming days.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 639 AM CDT Sat Oct 4 2025

VFR conditions are expected for the bulk of the forecast period.

Main aviation concern will be winds, potentially significant,
with gusts approaching 40 knots. These stronger gusts are likely
to affect much of west central Nebraska including both LBF/VTN
terminals. Later this evening, strong gusts will continue with
stronger winds off the surface leading to increasing LLWS
concerns. Rain and thunderstorms will attempt to move in from
the west, however, confidence in impacts leading to anything
MVFR or worse are low at this time. Winds will eventually flip
to the west as a front traverses the area with winds subsiding
quickly thereafter. Can`t rule out some low stratus in its wake
but will keep VFR conditions for now and evaluate trends going
forward.

&&

.FIRE WEATHER...
Issued at 402 AM CDT Sat Oct 4 2025

Critical fire weather conditions will exist Saturday, largely due to
very strong wind gusts ahead of a cool front. Red Flag Warnings
remain in effect for all fire weather zones in the local forecast
area as a result.

Early morning winds are already showing gusts around 20 to 30 mph
and these should continue through daybreak with strengthening during
the day. As an elongated surface low forms/deepens along the frontal
zone later today, winds will increase due to a tightening pressure
gradient ahead of a cool front which should settle along/near a line
from the central Panhandle into the Sandhills then up into south
central South Dakota. While low-level moisture advection will be
strong across eastern Nebraska, the stronger southerly flow further
west will promote stronger kinematics with mixing heights
approaching 10kft across southwest Nebraska into the central/eastern
Sandhills. As daytime highs climb into the upper 80s to lower 90s,
the deeper mixing will promote drying as dew points fall to the
upper 30s/near 40F. This will drive afternoon humidity minimums to
around 20 percent with a few locations seeing upper teens for a few
hours. While this remains above critical levels, strong winds with
gusts up to 45 mph will likely support erratic behavior and the
rapid spread of any fire starts. Eventually by late afternoon,
convection across the Panhandle and southwest South Dakota will
propel the frontal boundary south and east. Precise timing of this
frontal passage is medium confidence at best but thoughts are Zone
204 should be cleared by around 8-9pm MDT and Zone 206 cleared by
10pm-Midnight CDT. Richer boundary layer moisture will exist behind
this feature and while an abrupt wind shift from south to northwest
will accompany this front, moisture will quickly increase as well
with many locations likely seeing > 80% relative humidities before
Midnight CDT. Earlier concerns about dry lightning have decreased
with heavier QPF and the quick to increase boundary layer moisture.
Have a few locations near 0.50" closer to the Pine Ridge but wetting
rain potential (> 0.25") remains limited outside Zone 204 and far
western Zone 208. Winds should remain strong out of the south ahead
of the front but once FROPA occurs, expect a fairly steady decrease
with many locations seeing < 20 mph winds the remainder of the
night. Humidity recovery appears to be good for all of western
Nebraska with 80% for all by daybreak Sunday and many locations
surpassing 90%.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon CDT /11 AM MDT/ today to 10 PM CDT
/9 PM MDT/ this evening for NEZ204-206-208>210-219.

&&

$$

SHORT TERM...NMJ
LONG TERM...NMJ
AVIATION...NMJ
FIRE WEATHER...NMJ