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Area forecast discussion 
National Weather Service Omaha/valley NE
255 PM CDT Monday Aug 3 2015

Short term...(tonight through thursday)
issued at 254 PM CDT Monday Aug 3 2015

Models are in good agreement advertising a quite noticeable cooling
trend over the next several days. All this in part to northwest flow aloft
bringing a Canadian air mass into the lower 48 with the brunt of cold air advection
dropping down through the Great Lakes region.

Precipitation chances the next several days revolving around surface boundary
movement over the central and northern plains with series of vorticity maxes
lending support. Pop forecast this forecast issuance somewhat problematic at
this point given variance quantitative precipitation forecast field amongst models in regards to
eventual amounts/placement of precipitation. The nam12/gfs20 both favoring
two distinct areas of accumulate...one over eastern South Dakota and the other over
eastern KS/MO. On the other hand...ecm/CMC both lay bulk of precipitation
mainly over eastern Kansas into MO. Note...the ecm is showing a secondary
axis of appreciable accumulate occurring over central Nebraska.

Models in good agreement placing lead shortwave trough over Montana/Wyoming at
06z later tonight with increasing synoptic scale lift/DPVA inducing
surface cyclogenesis over the western Dakotas. Precipitation prognosticated to break out
then along warm front/instability axis from about western South Dakota to northern MO.
Environment will be moisture rich with precipitable waters values around 1.5".
Given slow nature of lifting boundary coupled with strong 325k
isentropic upglide...there is a good chance for heavy rainfall
during the overnight hours mainly over the northern County Warning Area. On Tuesday models
forecast second area of precipitation development over Kansas associated with a
strengthening warm front. Tuesday night/Wednesday precipitation prognosticated to expand
northward and encroach the County Warning Area. Next round of precipitation possible on Thursday
associated will a cold front moving into the region.

Long term...(thursday night through monday)
issued at 254 PM CDT Monday Aug 3 2015

Models persist showing a broad low amplitude ridge prevailing across
the Continental U.S.. precipitation chances during the extended periods involve a passing
cold front Thursday night...followed by a slow moving warm
front/moist 315k isentropic upglide Friday night through Sunday.
Otherwise expect slightly below normal afternoon highs heading into
next weekend.

&&

Aviation...(18z tafs for kofk...klnk and koma.)
Issued at 1207 PM CDT Monday Aug 3 2015

VFR conditions through the period. Weak cluster of thundershowers
could affect koma 1830-1930z. Showers could affect klnk 1800-1900z.
Otherwise...should be dry for several hours after that...but as a
weak impulse moves into the area late tonight...should see a 30
percent chance of thunderstorms at all 3 taf sites in the
04/08-16z period.



&&

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

$$

Short term...Dee
long term...Dee
aviation...Dewald

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