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272
FXUS63 KLBF 271738
AFDLBF

Area Forecast Discussion
National Weather Service North Platte NE
1238 PM CDT Thu Jun 27 2024

.KEY MESSAGES...

* An enhanced risk (risk level 3 of 5) of severe weather is possible
  this afternoon and evening with large hail up to 2 inches in
  diameter, severe winds up to 75 mph, and isolated tornadoes as the
  primary threats.

* Active weather continues Friday with a slight risk (risk level 2
  of 5) of severe weather for large hail and strong winds as the
  main threats.

* Quieter and cooler weather is expected for the weekend before
  increasing temperatures and isolated thunderstorm chances
  returns for next week with daily afternoon and evening
  thunderstorms.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 356 AM CDT Thu Jun 27 2024

The main weather concern in the short term will be the potential for
severe thunderstorms late this afternoon and evening. Dewpoints will
increase across the region ahead of a dryline providing increased
low level moisture across the region. Moderate instability will also
develop across much of north central Nebraska and the Sandhills by
mid afternoon. This ample instability will support the development
of supercells initially across northern Nebraska and portions of the
Panhandle. As these storms track southeast, storms will morph into a
convective line, possibly even take on QLCS characteristics. Current
model guidance suggests lapse rates above 7 C/km along with
significant CAPE (over 2000 J/kg). This combined with large CAPE in
the -10 to -30 degree C layer will support very large hail
(potentially up to 2+ inches in diameter). This environment will
also create the potential for significant wind gusts up to 75 mph or
greater. In addition to hail and strong winds, this environment will
be favorable for isolated tornadoes, especially initially when low
LCL heights and near surface storm relative helicity remains above
200. At this time, widespread flooding is not expected to be a
concern, although, some localized brief flash flooding could still
occur under some of the more intense thunderstorms falling on
recently saturated soil from earlier this week. Any impacts should
be short lived as storms quickly push off to the east.

There are some concerns heading into the severe potential this
afternoon and evening. Current radar shows lingering showers from
Wednesday evening. These showers will continue to slowly move
eastward throughout the morning hours. While not severe, these
showers may hamper the instability across the region. Even if
showers can push out early enough, stratus may continue to limit and
decrease the severe risk. If rain and clouds can not push out early
enough, storms will struggle to develop later in the afternoon. Even
if the environment can clear out enough across the Panhandle for
convection to initiate, if stratus is slow to dissipate across north
central Nebraska, storms will weaken significantly as they encounter
a more stable airmass. Still, a stronger storm could still survive
enough to produce hail up to 1 inch in diameter and winds up to 60
mph.

Instability decreases by late evening and storms will begin to
weaken heading into the overnight hours. Lingering rain Also, and
embedded thunderstorms are still possible, but the severe potential
will come to an end for the remainder of the overnight.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 356 AM CDT Thu Jun 27 2024

Another round of severe storms are possible on Friday as a cold
front gets dragged across Nebraska. Similar to Thursday, moderate
instability will exist along the frontal boundary along with ample
moisture. Storms are expected to develop across the Panhandle by mid
to late afternoon and push eastward, starting off as discrete
supercells before congealing into a line and eventually an MCS by
late evening/early Saturday morning. Large hail and strong winds
will be the initial threats along with an isolated tornado or two.
As the event transforms throughout the evening, the primary threats
will also evolve. By late evening (MCS stage), wind and heavy
rainfall will become the main hazards. Localized flooding and even
some flash flooding may be possible across areas that are already
saturated or experience training of storms. Showers and
thunderstorms will push into eastern Nebraska by Midnight CT
bringing an end to any severe concerns.

Upper level ridging across the western US will allow for surface
high pressure to build southward into the Great Plains on Saturday.
This will result in drier weather that is expected to last through
the weekend. In addition, cooler air will push in behind the
departing front dropping high temperatures nearly 10 degrees from
the low 80s to low 90s on Friday to the low 70s to low 80s on
Saturday. High pressure will continue to tap into the cooler
northern airmass on Sunday with similar highs on Sunday as on
Saturday.

Quiet and cool conditions will be short lived as active weather
returns for next week. Temperatures return to the mid 80s to mid 90s
(warmest to the south) through next Wednesday. This return to warmer
temperatures also will bring a return to increasing heat indices,
especially on Monday when some locations across southwest Nebraska
may briefly hit a heat index value above 100 degrees. At this time,
no heat headlines are in place, but if confidence continues to
increase in rising temperatures, they may be needed. In addition, a
series of disturbances will pivot across Nebraska keeping daily rain
and thunderstorm chances in the forecast. Severe storms are
uncertain at this time, but for now, these storms appear to be
diurnally driven and should quickly come to an end after sunset and
instability ceases. Stay tuned to later forecasts on severe
potential heading into next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
-- Changed Discussion --
Issued at 1236 PM CDT Thu Jun 27 2024

Severe thunderstorms are expected to develop in the Nebraska
Panhandle and move east into the early evening hours. Large
hail, wind gusts up to 50 KTS and visibilities as low as 1SM
are possible from 23z to 02z this evening at both the KLBF and
KVTN terminals. Thunderstorms will remain in the vicinity of
both terminals through late evening before exiting to the east.
In the wake of storms, skies will gradually clear with a shift
in wind direction to the north Friday morning.
-- End Changed Discussion --

&&

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

&&

$$

SHORT TERM...Kulik
LONG TERM...Kulik
AVIATION...Buttler