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711
FXUS63 KLBF 301939
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
239 PM CDT Sun Jun 30 2024

.KEY MESSAGES...

- A Marginal Risk (Level 1 of 5) of severe weather this evening
across portions of western Nebraska. Isolated thunderstorms may be
capable of producing severe wind gusts and produce large hail.

- A Slight Risk (Level 2 of 5) for severe weather returns on Monday
for most of western and north central Nebraska. All severe threats
are in play, to include large hail, damaging winds, and potentially
a few tornadoes.

- Precipitation chances remain through late week, with another
chance of strong thunderstorms on Wednesday.

&&

.SHORT TERM /THROUGH MONDAY/...
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Issued at 237 PM CDT Sun Jun 30 2024

Surface high pressure is located across the Mississippi Valley
region this afternoon. Return low-level southeast flow has developed
across Nebraska on the backside of the high. Low-level moisture
(surface dew points) are gradually rising as the southeast flow
originates from a tropical airmass (dew points 75-80F) across OK,
AR, LA and eastern TX. The best low-level moisture is being
transported through western KS into eastern CO and the Nebraska
Panhandle. Scattered thunderstorms will develop off the Laramie
Range within the increasingly moist upslope flow this afternoon.
Shear in this area is strong with modest instability, and a few
supercells will likely result. These will attempt to move eastward
into the Nebraska Panhandle late this afternoon and evening but will
likely struggle. Low-level lapse rates are poor as you move into
this area with weak CAPE. Shear is strong but the previous mentioned
factors will limit storm intensity and coverage as it moves
eastward. WAA in the mid-levels then increases after dark along with
an increasing southerly low-level jet. The nose of the jet is
pointed into central and eastern Nebraska. Expecting the initiation
of elevated convection to occur across central Nebraska after
midnight...becoming more widespread and organized as it tracks into
eastern Nebraska by sunrise Monday morning.

Attention then turns to the severe potential Monday afternoon and
evening. Southwest flow aloft will increase as a shortwave
embedded within the flow approaches. At the surface, low
pressure will deepen across northeast Colorado. A warm front
will lift northward and be located somewhere just south of I-80
by Monday afternoon. Low-level moisture will pool north of the
boundary with surface dew points rising into the lower 70s. This
moisture will combine with daytime heating and steep mid-level
lapse rates...creating potential extreme instability. There will
be a capping inversion in place, but forcing from the
approaching shortwave should help to overcome the cap with
convection developing by around 4 PM CDT. The storm mode will be
supercells, with the area near and just north of the warm front
looking quite favorable for tornado development. The exact
location of the warm front will have to be monitored carefully.
Storms will likely grow upscale into more of a line/QLCS type
system as the activity tracks toward eastern Nebraska Monday
evening.

Tuesday looks much quieter as a shortwave tracks across the
northern plains and drives high pressure southward into the
region. Return southerly low-level flow develops again
Wednesday. As low-level moisture returns to the area some
isolated/scattered late afternoon convection could develop.
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&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
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Issued at 237 PM CDT Sun Jun 30 2024

Upper level low pressure will move slowly move across southern
Canada Thursday into the weekend. A cold front will slide
southeast through the area Thursday with a drier airmass moving
into the area Friday into the weekend. Only slight chances for
precipitation are expected during this time along with cooler
temperatures. In fact, Thursday and Friday highs only reach the
70s across northern Nebraska. Highs do moderate some for the
weekend, ranging from the 80s across northern Nebraska to the
lower 90s across southwest Nebraska.
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&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1259 PM CDT Sun Jun 30 2024

IFR and possibly LIFR ceilings will develop tonight and linger
into Monday morning as humidity increases from the south. There
will also be some spotty southerly low-level wind shear tonight,
but not expected to be widespread and have not included in area
TAFs at this time. Scattered thunderstorms are expected to
develop east of a line from MCK to ANW late tonight and move
into eastern Nebraska Monday morning.

&&

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

&&

$$

SHORT TERM...Taylor
LONG TERM...Taylor
AVIATION...Taylor