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Area forecast discussion 
National Weather Service Omaha/valley NE
354 am CDT Monday Sep 15 2014

Short term...(today through wednesday)
issued at 210 am CDT Monday Sep 15 2014

Scattered elevated thunderstorms had developed around midnight
generally along I-80 in low level warm air advection regime. These
pulsed up briefly but continue to weaken and move east this
morning. Another area of more widespread showers is ongoing across
eastern South Dakota and southern Minnesota associated with a
strong shortwave trough dropping southeast out of South Dakota.
These showers are expected to progress southeast through the
morning hours behind a surface cold front which extends across
northeast Nebraska at 08z. The front should be through all of the
County Warning Area by 18z today and so have ended showers from north to south
around that same time.

Cool high pressure will build into the region behind this and is
forecast to be centered over the County Warning Area by 00z/Tuesday and linger
overhead through the overnight. Temperatures should radiate out allowing
lows to drop into the upper 30s to lower 40s. Will need to monitor
for fog conditions with light and variable surface winds...especially
in river valleys.

Cool start to the day and weak return flow around the slowly
departing high Tuesday should keep highs in the upper 60s. Medium
range models do continue to bring precipitation chances into our
southwestern counties in warm air advection regime with veering nocturnal low
level jet Tuesday evening/night. Lack of good moisture return
could inhibit more widespread development...but a few elevated
thunderstorms cannot be ruled out and so will include a slight
chance pop.

Long term...(wednesday night through sunday)
issued at 210 am CDT Monday Sep 15 2014

Upper level ridge over The Rockies will begin to deamplify middle
week as it slides east over the Central Plains by early Friday.
There are a few small windows of opportunity under this ridge for
showers/isolated thunderstorms with increasing isentropic upglide
in warm air advection zone...especially in our western counties Wednesday night
through Thursday.

Friday night/Saturday time frame will be complicated as a northern
stream shortwave drops a cold front into the Central Plains. In
addition...medium range models continue to bring tropical
moisture and remnants from what is now Hurricane Odile across The
Four Corners region and into the Central Plains just ahead of the
approaching cold front. Will have to monitor how this all plays
out and if a split upper level flow does indeed pan out. Tropical
moisture would give the area potential for heavy rainfall in
association with this northern stream boundary.


Aviation...(06z tafs for kofk...klnk and koma.)
Issued at 1139 PM CDT sun Sep 14 2014

Scattered showers and thunderstorms will affect koma/klnk through
about 10z. Otherwise...a cool front will move moving south into
the area...and could bring additional showers and MVFR ceilings...
initially at kofk by 10z...and then at klnk/koma by 11-12z.
Easterly winds become northeast...then north with the arrival of
the front. Once the front arrives...winds increase to around 12
knots or above...with gusts up to around 18 knots. Skies become
VFR again by 16z.


Oax watches/warnings/advisories...



Short term...Kern
long term...Kern

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