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Area forecast discussion 
National Weather Service Omaha/valley NE
604 PM CDT Monday Jul 6 2015

Short term...(tonight through thursday)
issued at 330 PM CDT Monday Jul 6 2015

The forecast concerns in the short term will be lingering showers
and thunderstorms and precipitation chances Tuesday night through
Thursday...if smoke should be included in the forecast...
cooler...below normal highs.

We've had a several rounds of precipitation today with the main area
of heavy rain per WSR-88D radar south of Nebraska City. At
20z...scattered showers continued as far back as Logan Omaha and Lincoln. The 12z oax sounding from this
morning was cut short due to thunderstorm contamination.

From the upper air maps...there was upper level divergence with the
right rear entrance region of the jet and this lift continues with a
maximum shifting into missuouri this evening. The 500 mb lead trough
has been moving through...with the main 500 mb trough still over
northern Minnesota into South Dakota. Water vapor satellite
imagery/lightning shows middle level moisture over the plains with
thunderstorms clustered over southeast Nebraska/southwest Iowa
into northwest and parts of Kansas. Dewpoints were still in the
70s over far southeast Nebraska and southwest Iowa...however drier
60s were working in with the cold front and the brisk north winds.
Smoke was creating hazy conditions and reduced visibilities for
parts of northeast Nebraska.

The latest Storm Prediction Center mesoanalysis has the maximum MLCAPE to the south of the
forecast area...however the 2.2 inch maximum precipitable water is still across
southeast Nebraska and southwest Iowa. Forcing is weaker...however
there is still some forcing aloft with the warm air advection and
lingering 850 mb and 700 mb moisture. Will continue to nudge probability of precipitation down
during the evening as the cold front pushes into Kansas and
Missouri. Brisk north winds will gradually decrease after
midnight and surface high pressure will be building in. Some patch
fog is possible with the wet ground and decreasing winds aloft.

Smoke has been reducing visibilities and our coop observer in
Bloomfield can now smell the smoke. The smoke forecasts show smoke
in parts of our area tonight and Tuesday. Will include it in the
zone forecast for parts of northeast Nebraska this evening.
Forecasters can assess if the smoke is thick enough to include

The next longwave trough tracking through Canada into the plains
will return deeper moisture Tuesday night and Wednesday. The 18z
NAM is more aggressive with the northward progress of the
precipitation ahead of the front. Do have some rain chances for
far southeast Nebraska and southwest Iowa for now. Scattered
thunderstorms are mentioned with the shortwave on Thursday.

Cooler...below normal highs in the 70s are forecast Tuesday
through Thursday.

Long term...(thursday night through monday)
issued at 330 PM CDT Monday Jul 6 2015

Thursday night through Saturday...the area will be prone to upper
level weather disturbances tracking from rockies into the central
and northern plains. Deep moisture is in place and the atmosphere
should be uncapped through Saturday morning...thus scattered
thunderstorms will be possible with each shortwave. Highs in the
80s for Saturday with 80s and 90s for Sunday and Monday.


Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 556 PM CDT Monday Jul 6 2015

Clouds and gusty north winds will gradually diminish from north
to south this evening. The main issue overnight will be
haze/smoke/fog. Kofk is already has reduced visibilities and would
expect klnk and koma to follow.


Oax watches/warnings/advisories...


Short term...zapotocny
long term...zapotocny

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