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fxus63 klbf 172332 aaa 

Area forecast discussion...updated
National Weather Service North Platte NE
632 PM CDT Sat Aug 17 2019

Short term...(this evening through Sunday night)
issued at 327 PM CDT Sat Aug 17 2019

Today through Sunday night. Thunderstorm chances this evening and
tonight highlight the near term. The northern stream remains active
as a positively-tilted shortwave advances across southern the
southern Canadian prairies. The wave will drag a front south from
the Dakota's late afternoon and serve as a focus for strong to
severe thunderstorm development. The trend of the cams has been
north into South Dakota, though there's still support for
development on the southern edge as far south as our northern tier
of counties, especially as the storms across the north converge and
surge east. Gusty winds will be the primary threat from the northern
convection, but severe hail cannot be ruled out. Across southwest
Nebraska there's support from the cams for isolated to scattered
thunderstorms. Storm initiation is underway across the High Plains
with the models moving the storms into southwest Nebraska after 21z
this afternoon. Some upgrowth is anticipated with the clusters
mainly targeting areas south of the Interstate. Steep lapse rates
and MLCAPES of 1000-2000 j/kg and shear of 30-40kts would point to
a large hail threat initially, but as the upgrowth occurs, damaging
wind would be the primary impact.

The aforementioned cold front will cross the region overnight
leading to drier and cooler conditions for Sunday. The latest
guidance supports mid-70s to lower 80s for highs.

Long term...(monday through saturday)
issued at 327 PM CDT Sat Aug 17 2019

Beginning 12z Monday. The long term models show the expansion of a
594 dm ridge from the Desert Southwest through Tuesday with warming
temperatures and mainly dry conditions. Though as the upper high
drifts west over The Rockies, a front will serve as a focus for
convective development. There continues to be some disagreement as
to where the front will be during the peak heating hours, so an
argument can be made for just about anywhere across the forecast
area for storms.

Northwest flow aloft returns mid-next week with cooler temperatures
and near daily precipitation chances as sub-tropical moisture
moving in from the southwest. As the high builds further west and
flattens lesser moisture is shown for late week, but still enough
remains for at least an isolated storm or two.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 632 PM CDT Sat Aug 17 2019

Isolated to locally scattered thunderstorm coverage is expected
along and north of Highway 20 east of Valentine this evening.
Isolated thunderstorm coverage is expected elsewhere this evening.
No additional thunderstorm development is expected after 06z
tonight through Sunday afternoon.

A period of MVFR/IFR ceilings is expected to form with the
passage of a cold front overnight. This is expected to last from
06z tonight through 17z Sunday. VFR is expected thereafter
throughout wrn and ncntl Nebraska.


Lbf watches/warnings/advisories...

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