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Area forecast discussion 
National Weather Service North Platte NE
637 PM CDT Wednesday Aug 27 2014

Synopsis...
issued at 342 PM CDT Wednesday Aug 27 2014

Hurricane off North Carolina coast and hurricane off of Baja California. Weak
trough into the Great Lakes and large trough over the Great Basin
with Nebraska in the deformation zone. At the surface stationary
boundary across Nebraska Kansas border.

&&

Short term...(this afternoon through thursday)
issued at 342 PM CDT Wednesday Aug 27 2014

Another active weather night in store for western and north central
Nebraska tonight. Main upper level system is currently pushing into
northwest Colorado per water vapor imagery. Continued height
falls/good forcing aloft was noted to the east of this feature
across eastern Colorado into western Kansas and Nebraska. This is
supported by the continuous development of scattered showers and
thunderstorms in area of warm air and moisture advection from
western Kansas into central and western Nebraska. A very moist
airmass is in place this evening...with tropical precipitable water values of 1.50
to nearly 2.00 inches. As the upper level system continues to inch
closer to the area...and the southerly low level jet becomes
established early this evening...expect an uptick in showers and
thunderstorms. The main concern overnight will be the possibility of
heavy rainfall and even some localized flash flooding potential. The
threat for severe thunderstorms is low but not non-zero. The best
potential for a severe storm would be across southwest Nebraska late
this afternoon though early this evening...where a few breaks in the
clouds allowed for some surface based instability to develop.
Unfortunately... regrading the heavy rain threat...do not have a
good feel on exactly where the heavier rain bands will set up. For
this reason I will stick with the previous forecast which gave a
mention of locally heavy rainfall for all locations through the
night.

The main upper system will slowly move east across the forecast area
Thursday. Expect at least a scattering of showers and perhaps some
thunderstorms as this occurs. The heavy rain threat though should
have pushed east of the area...where the best moisture/warm air
advection will be located ahead of the upper system. Highs will kept
down once again from expected cloud cover...with mainly 70s
expected.

Long term...(thursday night through tuesday)
issued at 342 PM CDT Wednesday Aug 27 2014

Middle term models in good agreement and begin to diverge in the
extended. GFS in the extended with a strong Hudson Bay low while
the European model (ecmwf) has a broad trough through the northeast Continental U.S..
upper trough to the west will keep thunderstorms in the forecast
over western Nebraska through Thursday. Scattered thunderstorms
will continue Thursday night over eastern portions of the forecast
area. All activity to the east on Friday. More zonal upper air
pattern with fast moving waves through the weekend. Surface trough
along the Front Range Saturday moving off the Front Range Saturday
night into western Nebraska with thunderstorms developing over
the western sandhills along the trough axis Saturday night and
expanding early Sunday morning as the cool front moves into
northwest Nebraska. Ongoing showers through the day Sunday as the
front moves south through the day into Monday morning. Lows in the
50s and 60s highs in the 70s and 80s.

&&

Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 637 PM CDT Wednesday Aug 27 2014

Current radar indicates that lbf will have thunder in the area
through 03z. After that...there is considerable uncertainty
regarding the location and timing of showers and thunderstorms at
any one point in central and western Nebraska. Rapid update short
range projections indicate a possibility of thunderstorms at lbf and
vtn after 06z...but the probability decreases.

&&

Lbf watches/warnings/advisories...
none.
&&

$$

Synopsis...power
short term...Taylor
long term...power
aviation...Springer

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