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809
FXUS63 KLBF 300925
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
425 AM CDT Sun Jun 30 2024

.KEY MESSAGES...

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- 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.
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&&

.SYNOPSIS...
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Issued at 423 AM CDT Sun Jun 30 2024

Upper air analysis and satellite imagery place a trough over the
Great Lakes, with a ridge over the Dakotas, and another trough off
the West Coast. At the surface, a high pressure system is located
over eastern Nebraska. A stationary front tracks from Kansas to the
Texas Panhandle and along the front range of the Rocky
Mountains.
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&&

.SHORT TERM /THROUGH MONDAY/...
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Issued at 423 AM CDT Sun Jun 30 2024

A low pressure system is expected to deepen over Wyoming this
afternoon and track to the northeast. As the low interacts with the
front, a warm front will begin to slowly tack across the state of
Nebraska. Early this morning, a low level jet will provide southerly
flow bringing in a plume of Gulf moisture. The upper level dynamics
provide sufficient deep layer shear for organized convection, with
the main concern being the strength of the cap. With the ingredients
in place, the Storm Prediction Center has placed portions of western
Nebraska in a Marginal Risk for severe weather late this afternoon
into the evening. The primary concern will be for damaging wind
gusts and potential for large hail with more organized convection.
As of now, the main severe threat is further north, mainly over
Montana and North Dakota, however, stronger cells cannot be ruled
out along the warm front with ample low level moisture. The main
concern remains the strength of the cap and more stable air over
western Nebraska. In fact, overnight CAM guidance remains quite
bullish on the strength of the low level inversions, to the tune of
nearly 400 J/kg mixed layer CIN prior to convective initiation.

The severe weather set up on Monday appears more favorable. Although
an inversion is expected to remain, the cap looks less impressive on
Monday and more supportive of convective initiation. The low level
jet will continue to provide a source of Gulf moisture for storms on
Monday, and the slow moving warm front will provide a focus for
convective initiation on Monday afternoon. Forecast soundings show
fairly deep layer shear which will be supportive of supercells.
Given the environment, all severe weather hazards seem to be in play
Monday afternoon, including damaging winds, large hail and
potentially a few tornadoes. The Storm Prediction Center has most of
western and north central in a Slight Risk of severe weather for
Monday. More concerning, is the risk of significant hail, greater
than 2 inches in diameter, over portions of southwest, central, and
south central Nebraska. The conditions on Monday will need to be
closely monitored, as timing and location are honed in on.
Regardless, Monday appears to be a day to stay weather aware and a
day to have multiple ways to get updates and warnings throughout the
day.

In addition to the thunderstorm risk, Monday will be the hottest day
of the forecast period, particularly over southwest Nebraska. High
temperatures across southwest Nebraska will approach the upper 90s,
and may even break 100 degrees. The latest forecast sees a slight
cooling trend, with expected temps in the mid to upper 90s. However,
there still is a potential for the high to break 100 for a short
period of time Monday afternoon.
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&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
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Issued at 423 AM CDT Sun Jun 30 2024

The upper level trough remains to the west on Tuesday before
transitioning into a progressive upper level pattern. This will keep
chances of precipitation in the forecast through the end of the
week. By the weekend, a ridge should attempt to build in behind an
exiting trough, bringing a potential for another dry period.
However, there is some disagreement on the timing of the ridging
setting in. Cluster analysis highlights this bit of disparity,
however, as the week progresses, guidance should get a better handle
on the speed of the upper level systems.

On the note of near daily precipitation chances, Wednesday may be
the next day to keep an eye on for stronger thunderstorms. Wednesday
afternoon into the overnight hours brings the best chances for
widespread precipitation during the course of the week, with
generally seasonable temperatures. Both the GFS and the European
suggest a forming low pressure system over the Rockies tracking
through Nebraska, with disagreement on timing and track. The GFS in
particular is suggesting areas of modest CAPE and bulk shear
supportive of more organized convection, however the exact severe
potential is unknown at this time.
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&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1228 AM CDT Sun Jun 30 2024

VFR conditions through the afternoon, then lower clouds move in
across southwest Nebraska, including KLBF by late evening
bringing MVFR and potential lower conditions. For the northern
Sandhills into north central Nebraska, lower cigs are more
uncertain and have kept cigs above MVFR conditions for KVTN
through the forecast period. Winds will be gusty in the morning
and afternoon out of the southeast around 10 to 15kts and gust
of 25 kts. There is also a slight chance of showers in the
evening.

&&

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

&&

$$

SYNOPSIS...Richie
SHORT TERM...Richie
LONG TERM...Richie
AVIATION...Gomez