802
FXUS63 KLBF 262322
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
622 PM CDT Wed Jun 26 2024

.KEY MESSAGES...

- A Slight Risk (Level 2 of 5) for severe storms across
  portions of the Panhandle this evening, as storms forming in
  Wyoming track east.

- An Enhanced Risk (Level 3 of 5) for severe weather on
  Thursday, mainly along and west of Highway 83. A Slight Risk
  of severe weather remains in place for the rest of the region
  on Thursday. Primary severe concerns are large hail and
  damaging winds, with an increased tornado potential during the
  evening.

- Severe weather chances continue across the region on Friday,
  with a Marginal Risk (Level 1 of 5) across western and north
  central Nebraska.

- In addition to the severe weather threat, thunderstorms will
  bring the additional threat of locally heavy rainfall and
  localized flooding.

&&

.SYNOPSIS...
Issued at 320 PM CDT Wed Jun 26 2024

Upper air analysis and satellite imagery indicate a trough over the
eastern United States, with a ridge building over the Intermountain
West, with an upper level low off the Pacific Northwest. The current
pattern places northwesterly flow aloft over western Nebraska. At
the surface, a low pressure system is located over south central
Kansas this afternoon, with a stationary front extending east and a
cold front extending to the west. On satellite, thunderstorms are
observed initiating over Wyoming.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 320 PM CDT Wed Jun 26 2024

A Slight Risk (Level 2 of 5) exists for severe thunderstorms across
portions of the Nebraska Panhandle late this afternoon into the
evening. Storms are expected to initiate off the Laramie Range this
afternoon and track across eastern Wyoming. Potential exists for a
bit of storm growth in a narrow corridor of better CAPE across
southeast Wyoming and the western Nebraska Panhandle. As storms
track into the eastern Panhandle, they will encounter a
strongly capped airmass, and are expected to weaken prior to
reaching the Sandhills. The primary severe weather concerns this
evening will be large hail and damaging wind gusts from storms
moving into the region, and primarily before storms weaken.


A much stronger severe weather set up is expected for Thursday.
Overnight Wednesday, the upper level ridge should progress eastward,
setting up an upper level trough over Montana and Wyoming by
Thursday afternoon. Ample low and mid level moisture advection is
expected over the central plains, with dewpoint temperatures in the
60s. As a deepening low pressure system sets up over Montana and
tracks through the Dakotas, storms are expected to initiate along
the accompanying surface boundaries in the late afternoon. As storms
begin to track towards Nebraska, a southerly low level jet is
expected to intensify, which will lead to an increase in low level
wind shear. One of the main forecast challenges tomorrow is
determining how much surface heating will occur, which will likely
impact expected storm modes. If skies can clear allowing better
daytime heating, the potential for discrete supercell thunderstorms
increases, before storms eventually morph into a linear system. If
the daytime heating remains more limited, then a more linear storm
mode is likely to prevail. Either way, with ample moisture,
sufficient shear, and upper level dynamic support, the Storm
Prediction Center has issued an Enhanced Risk (Level 3 of 5) for
severe weather across western and north central Nebraska. The
Enhanced Risk is mainly for areas along and west of Highway 83, with
the rest of the region in an Slight Risk. The main severe weather
concerns are large hail and damaging wind gusts, however once the
low level jet intensifies, the potential for tornadoes also
increases.

In addition to the severe weather threat, these storms will be
capable of producing locally heavy rainfall. With the strong
moisture advection expected ahead of these storms, forecast moisture
profiles are quite moist from the surface through the upper levels.
Expected PWAT values around 1.3 inches are generally at or above the
90th percentile compared to climatology across western and north
central Nebraska. With precipitation mainly falling in
thunderstorms, this complicates determining where the heaviest
precipitation will occur. In general, expecting rainfall through
Friday morning to be one half inch or greater across most of the
region, however, locally heavier rainfall amounts are expected. In
areas where there has been recently ample rainfall, this may
increase the potential for localized flooding.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 320 PM CDT Wed Jun 26 2024

Another round of severe weather may remain for Friday, with a
Marginal Risk (Level 1 of 5) for severe weather across western and
north central Nebraska. At this time, the primary severe weather
threat appears to be further east, across southeast Nebraska, Iowa,
and Missouri. A lingering risk may remain through the early morning
hours, with some guidance suggesting additional redevelopment late
Friday afternoon across southwest Nebraska. At this time, the
convective mode is a bit uncertain, as well as the primary severe
weather concerns. Otherwise, an additional rain chance continues
through Saturday morning, with temperatures remaining on the cooler
side of climatology through the weekend.

Sunday through Monday, upper level ridging is expected to pass over
the region, bringing a return to seasonal to above seasonal
temperatures. The upper level pattern is currently expected to
remain on the more progressive side next week, which should keep
moving a series of ridges and troughs. With lower confidence in
placement of the upper level pattern, continued with the mean NBM
guidance, keeping a slight chance of showers through early week, and
generally seasonal temperatures. As guidance gains a better handle
on the upper level pattern, should see confidence increase in
potential precipitation and temperatures.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 621 PM CDT Wed Jun 26 2024

A developing area of showers and thunderstorms across ern WY
will move east through wrn/ncntl Nebraska overnight. Scattered
coverage appears likely. This flight concern will be east of the
area by 18z Thursday.

Another flight concern is the potential for MVFR/local IFR
ceilings developing around 12z Thursday morning and lasting
until 21z Thursday afternoon. The stratus should develop from
south to north Thursday morning and is the result of rapidly
increasing low level moisture.

Lastly, isolated thunderstorms are possible from 21z Thursday
afternoon onward with the best chance across wrn Nebraska, along
and west of highway 61.

&&

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

&&

$$

SYNOPSIS...Richie
SHORT TERM...Richie
LONG TERM...Richie
AVIATION...CDC