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Area forecast discussion 
National Weather Service North Platte NE
321 am CDT Monday Jul 28 2014

Short term...(today and tonight)
issued at 320 am CDT Monday Jul 28 2014

Stationary boundary lies across the eastern plains of Colorado
where upper level disturbances are again interacting with it early
this morning. Upper low over the southern Hudson Bay continues to
sharpen the ridge in the west leaving the northern plains in fast
northwest flow. Cool surface high over the northern plains will
continue to keep temperatures slightly below normal for the
season. Middle and high clouds are again expected to affect mainly
southwest Nebraska today as the mesoscale convective system over southern Colorado
continues to spread cloud shield to the north. Easterly flow over
southwest Nebraska will gradually become southerly through the day
as surface high builds south. 850mb temperatures support surface
temperatures similar to yesterdays with some upper 70s over
northern Nebraska. Upslope flow over the Nebraska Panhandle will
provide some orographic lift this evening as well as some
returning moisture across the southwest into the eastern Nebraska
Panhandle. Low level jet will develop through the evening across
the eastern Nebraska Panhandle and Keith...Perkins and Chase
counties and focus across this area through the over night. Expect
isolated thunderstorms to develop over the eastern plains of
Wyoming along the stationary boundary this afternoon and move into
the Nebraska Panhandle through late afternoon and then try to move
east through the sandhills as the low level jet kicks in. No
strong waves moving through so would expect thunderstorms to
remain anchored to the higher terrain and diminish as they move
east into more stable air. Lows tonight 50s north and 60s south.

Long term...(tuesday through sunday)
issued at 320 am CDT Monday Jul 28 2014

Little change is expected in terms of the large scale flow through
next weekend as ridging will remain across the western part of the
country...with troughing anchored from Hudson Bay through the deep
south. With this pattern...the northern and Central Plains will be
under the influence of northwest flow. In general...the main storm
tracks will be east of the region with shortwaves digging into the
trough...and west of the area with shortwaves rounding the top of
the ridge. There may be a chance for some showers and
thunderstorms Tuesday into Wednesday...but otherwise the forecast
for the remainder of the next 7 days will be dry.

For Tuesday through Wednesday...the upper level jet will move
through the Missouri River valley which will put the local area in
placement for good large scale lift being in the right entrance
region of the jet streak. There are also indications of a weak
shortwave in the middle levels passing through central South Dakota
into north central into eastern Nebraska. There is some moisture
transport into these areas indicated at 700mb by the NAM and the
GFS and with models also showing some middle level frontogenetical
forcing with the front at 850mb-700mb roughly from western Cherry
County through khgi. Although instability is weak...there could be
enough moisture and lift to spark the development of some showers
and thunderstorms through the day along the middle level boundary.
Confidence isn/T high on this occurring so will stick to the
slight chances for this forecast package.

Tuesday afternoon into Wednesday several stronger shortwave
troughs will round the upper level ridge...passing over northern
Colorado into Kansas and Oklahoma. There will be fairly decent
moisture transport in the low levels into these systems as the
models are showing 60 to 65 degree dewpoints advecting into
eastern Colorado. appears the
moisture/convergence...and associated lift will be focused south
and west of the local area so have started shifting precipitation
chances to the south. Is currently looking like rainfall will be
mainly across northeast Colorado into western Kansas.

For Thursday night and Friday the models are in agreement showing
a shortwave trough digging into the trough out of southern Canada.
The Gem is strongest with the shortwave as it brings some
precipitation as far west as Highway 83. At this time...with this
being the only model showing this occurring will keep with the
consensus solution having the forecast dry for Thursday through
the weekend. Backtracking a bit...the NAM is doing something
similar for Wednesday afternoon through and Wednesday
night...bringing a shortwave down through eastern South Dakota
into northeast Nebraska. If this would occur...could see some
showers over north central and central Nebraska. This is the only
model producing this shortwave this far west so at this point will
ignore it but will keep it in mind in coming forecasts.

In terms of temperatures...the placement of the upper level
pattern will keep the main airmass boundary to the west of the
local area. So looking at slightly below normal temperatures for
much of the forecast area with highs for most locations in the low
to middle 80s. By Sunday the models are showing the ridge building
east slightly so looking for a warming trend for the last part of
the weekend and into the first part of next week.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 105 am CDT Monday Jul 28 2014

VFR conditions for the klbf and kvtn terminals. Winds will remain
light below 10kt through the next 24 hours. Mainly clear skies
overnight should increase to scattered-bkn080 after 12z. &&

Lbf watches/warnings/advisories...


Lbf watches/warnings/advisories...


Short term...power
long term...Brooks

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