084
FXUS63 KLBF 192101
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
401 PM CDT Sat Oct 19 2024

.KEY MESSAGES...

- Warmer temperatures and breezy conditions expected to start
  the week as a storm system approaches the area. Precipitation
  potential will remain limited to mainly southwest through
  south central Nebraska.

- The only interruption to an otherwise dry forecast beyond
  Monday is a frontal passage late Tuesday into early Wednesday
  but recent trends cast doubt on much if any appreciable
  moisture.

- Temperatures return to well above normal values for the latter
  half of the week with growing fire weather concerns as a
  result.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 401 PM CDT Sat Oct 19 2024

Satellite analysis shows widespread low-level cloud cover across
much of the forecast area. This is gradually eroding from the
northwest which is allowing temperatures to rebound nicely under
sunny skies. Further southeast, under lingering overcast skies,
temperatures have struggled to climb with many locations holding
firm in the middle 50s.

The surface boundary remains southeast of the forecast area, as
indicated by a converging line extending from northwest Kansas up
through south central Nebraska. This feature is unlikely to move
much and it is likely to become washed out this evening as southerly
flow increases. A strong LLJ will develop across western Nebraska
which will likely limit overnight lows as steady south to
southwesterly winds persist overnight. Expect overnight lows to fall
into the 40s to 50s which will be nearly 20 degF above normal.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 401 PM CDT Sat Oct 19 2024

Sunday and Monday...deep cut-off low across the Desert Southwest
will begin to translate east into the central and southern Rockies.
Enhanced southerly flow will support rapid moisture transport with
NAEFS guidance suggesting WV transport exceeding the 90th percentile
into western Nebraska. PWATs as a result will respond accordingly
with values similarly exceeding the 90th percentile by midday
Sunday. Temperatures will climb quickly aloft as h85 climb into the
middle teens degC. Height falls increase quickly late in the day
Sunday as the h5 trough quickly crosses the central Rockies. While
moisture will be on the increase, forecast soundings show a slow
saturation of the profile. This is likely due to the greatest
moisture transport quickly shifting east as the main low aloft
tracks just east of the area. Sunday afternoon highs will climb into
the 70s to low 80s with these warmest values east of Highway 183.
Precipitation potential has decreased slightly as well, with the
greatest forcing now focused across central Nebraska. NBM, EPS, and
GEFS probabilities for QPF have decreased locally with a sharp
cutoff from the northwest to southeast. Even NBM 90th percentile
suggests little precipitation potential northwest of an Ogallala to
O`Neill line. Decided to limit the spatial coverage of Chance PoP
categories (> 25%) to more closely match peak GEFS/EPS
probabilities. As southwesterly flow continues in the mid-levels,
lapse rates will steepen and and lead to modest instability across
the area while afternoon highs reach the upper 60s to low 70s. While
SREF and NAM both indicate widespread instability values nearing the
500-1000 j/kg range, deep layer shear will be limited to around 20
knots. The Storm Prediction Center introduced a Day 3 (Monday)
Marginal Risk for portions of the Central Plains. Have no issues
with keeping this threat area to our southeast. Precipitation
chances peak Monday morning through the afternoon as DCVA is
maximized within broad WAA. Again, with thinking that focus is to
the east, will limit PoPs across the Sandhills prior to the end of
precipitation chances by early Monday evening as the trough axis
clears the area.

Tuesday and beyond...a deep trough across central Canada will
amplify and dive southeast into the Great Lakes. This will deepen a
surface low near the Hudson Bay with an attendant cold front
extending southwest into the northern Plains. This frontal boundary
will move into western Nebraska late Tuesday. Model blend output
produces low-end PoPs across our northern zones late Tuesday into
early Wednesday. NWP guidance continues to vary on precipitation
chances, with ECMWF and EPS solutions depicting some light QPF while
the GEFS and GFS keep everything north of the immediate area. Did
opt to limit categorical PoPs to Slight Chance (< 25%) given limited
confidence and light QPF even from the more bullish solutions. High
pressure building in Wednesday will allow a swift end to any
precipitation potential and return dry conditions to the forecast.
Late week, upstream ridging will amplify with slight northwesterly
flow aloft locally. The extended forecast will favor positive height
anomalies and thus temperatures warming through the end of the week.
Middle to upper 70s for high temperatures appears probable for
Thursday and Friday which will approach 20 degF above normal for
late October. Though timing remains somewhat in question, a return
to troughing in the west will foster a ridge breakdown sometime
around Friday or Saturday. This will promote increasing fire weather
concerns though precise details remain murky at the present
time.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1225 PM CDT Sat Oct 19 2024

Low stratus with IFR/MVFR CIGs will continue to gradually
improve this afternoon, with widespread VFR expected to return
by tonight. Winds shift southerly this afternoon and this
persists through the end of the valid period. Winds then strengthen
from the south tomorrow afternoon, with gusts of 20 to 30kts.

&&

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

&&

$$

SHORT TERM...NMJ
LONG TERM...NMJ
AVIATION...Brown