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Area forecast discussion 
National Weather Service Omaha/valley NE
353 PM CDT Tuesday Jul 7 2015

Short term...(tonight through friday)
issued at 330 PM CDT Tuesday Jul 7 2015

Forecast concerns in the short term will be chilly temperatures
and patchy fog...then isolated showers for parts of the area
Wednesday and how far north the widespread showers and
thunderstorms will make it Thursday night.

Quite cool for this time of year and even near a record at Eppley
Airfield this am. Temperatures dropped to 54 degrees and the
record low set in 1908 is 52. Surface high pressure prevails
across the area with northeast winds and temperatures only in the
60s and 70s. Again tonight...light surface winds are expected and
temperatures should again drop into the 50s...with some 40s in
local cold spots. The records for Wednesday morning are 51/50/48
at Omaha/lnk/ofk...set in 1891/1891/1920 respectively. Some patchy
fog may develop in Platte and Elkhorn river valleys.

At 500 mb...the leading trough stretched from Canada into the Great
Lakes and another trough was over western Canada into the Pacific
northwest...with 500 mb closed low pressure off the West Coast.

The deeper moisture and the 850 mb front is near Kansas City and a
few sprinkles/showers were noted there. Precipitable waters were .5 to 1 inch
over the forecast area...however were closer to 1.5 inches toward
Kansas City. Overnight...there is some weak lift. The 850 mb front
lifts farther north toward Falls City and southern Iowa Wednesday.
Heavy rain is going to be a concern for parts of Kansas and
Missouri. Parts of eastern Nebraska and southwest Iowa could get
clipped with a few showers/sprinkles as moisture wraps around the
850 mb circulation back into the forecast area from Missouri and
precipitable waters increase to 1.5 inches for this area. The 500 mb trough swings
through across Canada with a weak reflection in our area Wednesday
night and pushes the moisture southward slightly.

The closed 500 mb low is prognosticated to be centered over California
Thursday and the 850 mb flow increases across Kansas...lifting into
the southern half of the forecast area Thursday night.
Meanwhile...there is some shortwave trough energy to work with and
precipitable waters have returned to 1.5 to 2 inches. Scattered showers and
thunderstorms should begin to increase and spread northward
Thursday with likely probability of precipitation Thursday night...shifting eastward
Friday. The operational models vary on how far north the heavier
rain will make it. The ec backed off somewhat compared to the
NAM/GFS and was closer to the UKMET. Will make adjustments if
needed...but for now have likely probability of precipitation over the southern half of
the County Warning Area.

Long term...(friday night through tuesday)
issued at 330 PM CDT Tuesday Jul 7 2015

Drier and hotter for the extended...however shortwaves topping the
ridge could produce periods of thunderstorms.

&&

Aviation...(18z tafs for kofk...klnk and koma.)
Issued at 1145 am CDT Tuesday Jul 7 2015

Generally look for VFR conditions at the taf sites through the
period. Some fog or haze possible late tonight but confidence was
not high enough to mention at this time. North/northeast winds
will gradually veer to east/southeast.

&&

Oax watches/warnings/advisories...
NE...none.
Iowa...none.
&&

$$

Short term...zapotocny
long term...zapotocny
aviation...Miller

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