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Area forecast discussion 
National Weather Service Omaha/valley NE
1154 PM CDT Wed Oct 26 2016

Short term...(tonight through saturday)
issued at 309 PM CDT Wed Oct 26 2016

Early-afternoon water vapor imagery revealed a de-amplifying mid-
level trough from the upper Great Lakes to Ozark Plateau with an
upstream ridge gradually building east through the interior west.
In the low levels, a surface low was located over east-central
Iowa as of 18z with a trailing cold front which stretched through
northwest Missouri into south-central Kansas.

The western edge of a Post-frontal stratus cloud deck should
continue to erode from west-to-east across the area in concert
with strengthening deep-layer subsidence. The decreasing clouds
coupled with diminishing winds and a reasonably moist boundary
layer will likely yield areas of fog tonight into Thursday

Thursday, the western U.S. Ridge will begin to flatten as it edges
east of The Rockies, hastening the deepening of a Lee trough over
the High Plains. As a result, strengthening southwest low-level
flow will promote notably warmer temperatures, especially across
our western counties where highs will reach the mid to upper 70s.
Friday into Friday night, a polar-branch short-wave trough will
temporarily dampen the north-central U.S. Ridge and drive a cold
front into the area. A seasonably warm air mass will persist
ahead of the cold front with highs on Friday potentially reaching
the lower 80s at some locations. For reference, record high
temperatures for the 28th (fri) are: Omaha - 84, Lincoln - 84,
and Norfolk - 85.

Cooler temperatures are expected on Saturday with a low-
probability chance of light rain over far northeast Nebraska.

Long term...(saturday night through wednesday)
issued at 309 PM CDT Wed Oct 26 2016

Mid-level heights will rebound over the northern plains Saturday
night through Sunday in advance of short-wave trough moving
through the interior west. By Monday, we begin to see differences
in 12z medium-range guidance with respect to the timing and
amplitude of this trough as it moves across the northern and
Central Plains and into the upper Great Lakes. The GFS is more
progressive and amplified with this features than the gefs mean,
the European model (ecmwf) and Canadian models. Accordingly, the GFS advances a
surface cold front through the area much sooner than the other
models. The preferred slower solution would suggest well-above-
normal temperatures on Monday with highs in the mid to upper 70s.

We will see cooler temperatures with the passage of the cold front
on Tuesday and Wednesday with a low-probability chance of showers
and thunderstorms.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1146 PM CDT Wed Oct 26 2016

Light winds and low dewpoint spreads should favor areas of fog
development tonight. The stratus is hanging close to koma, however
should nudge east and this last hour had scattered at komas. High
clouds could hinder dense fog development, however klnk appears to
have the best chance for these lower visibilities. Included
deteriorating conditions with MVFR/IFR/LIFR restrictions due to
fog. Kofk should see winds increase toward morning and this
should limit dense fog and did not mention vsbys lower than 1mi at
this time. 25 to 35kt low level winds will mix southwest winds to
10 to 20kts toward mid day. Included low level wind shear in the
evening as 40+kt winds develop.


Oax watches/warnings/advisories...


Short term...Mead
long term...Mead

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