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Area forecast discussion 
National Weather Service Omaha/valley NE
323 am CDT Sat Aug 23 2014

Short term...(today through monday)
issued at 323 am CDT Sat Aug 23 2014

Closed upper trough remains across the Pacific northwest while
lead wave continues to lift northeast through the middle Missouri
Valley region. Meanwhile...surface low across western Kansas with
a warm front extending east northeast into northwest Missouri and
southern Iowa will also lift north this morning...pushing a
widespread area of showers and storms north of the front with it.
The area of persistent rain should be almost north of the region
by 12z...but could linger for an hour or two along and north and
east of the Missouri River. Spotty showers also across western
Kansas could move into eastern Nebraska yet this morning...which
hrrr/rap both indicate. With warm front moving north of the
region this afternoon...southerly winds of 15 to 25 miles per hour will help
to boost temperatures to the upper 80s to middle 90s most locations. Most of
the area will also stay dry early in the afternoon...but eastern
Nebraska could begin to see a slight chanceeign of a late
afternoon thunderstorm...but better chance just west of the
forecast area across central Nebraska.

For tonight...a weak cool front approaches the region from the
west. Forecast area will remain in on the warm/unstable side of
the boundary...and while not expecting rain like we have had this
morning...low level moist jet axis could trigger isolated storms
for most areas...thus will maintain the 20 percent chance that we
already had in the forecast. This weak front continues to make
forward progress into the forecast area on Sunday. Atmosphere
will likely be capped with h70 temperatures in the +11/+12 range...but
could be enough support for a 20 percent chance along the front
by late afternoon.

The boundary stalls in the region Sunday night near or along i80...
which again could provide enough focus for a 20/30 percent chance
of storms. This boundary then lifts slightly north on Monday...which
will delineate upper 70s north to middle 90s south across the forecast
area...with decent bust potential based on where front sets
up...but still providing a focus for thunderstorm development.

Long term...(monday night through friday)
issued at 323 am CDT Sat Aug 23 2014

Thunderstorm chances continue Monday night through Wednesday night
as the aforementioned front remains stalled in the region...providing
the necessary focus for additional storm development...especially
north of the boundary through the period. This will result in scattered
to numerous storms early in the week...especially across north/northwestern
portions of the forecast area. Models also differ on timing the
precipitation out of the region with European model (ecmwf) remaining very slow and definitely
cooler...while the GFS sweeps the trough further east. Will go
with a dry forecast Thursday/Friday for now...and will monitor
later European model (ecmwf) model runs and adjust if necessary.


Aviation...(06z tafs for kofk...klnk and koma.)
Issued at 1130 PM CDT Friday Aug 22 2014

A strengthening low level jet in response to shortwave energy
lifting out of an upper trough to our west will bring scattered
thunderstorms to eastern nebr tonight and activity should impact kofk
the longest. Although gusts over 40kts have been observed with
initial line moving northeast...earlier convection in the kofk
vicinity could have provided enough low level stabilization to
keep wind gusts a little below that threshold there...and the same
case could be made for koma. Later tonight MVFR ceilings...or possibly
lower...especially at kofk...should develop in response to areas
of heavy rain. Fog is also a decent bet toward morning as/if
shower activity would spread north of area...and MVFR mention was made
with visibilities as well. Some thunderstorm risk could linger into
Saturday in northestern nebr and additional storms should develop west of
the region Sat aftn/evening. But for now mention was left out of
taf sites as activity into Saturday afternoon was uncertain at kofk and
impact of any development over High Plains would probably be late
in the period.


Oax watches/warnings/advisories...


Short term...Dewald
long term...Dewald

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