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Area forecast discussion 
National Weather Service Omaha/valley NE
421 am CDT Wednesday Apr 16 2014

Short term...(today through friday)
issued at 412 am CDT Wednesday Apr 16 2014

Good model agreement this morning pattern aloft will be progressive
in nature across the Continental U.S. With several embedded northern stream
shortwaves moving through. However...precipitation chances through the near term
periods look rather small with focus more or less found north and south
of the County Warning Area.

First round comes this afternoon over the northern County Warning Area in relation to a spunky
little vorticity maximum crossing the northern plains. Stout layer differential
divg/isentropic upglide will aid in synoptic scale ascent...but
forcing will be most prevalent over the Dakotas and upper Midwest.
Dynamic forcing though will be close enough to justify small probability of precipitation
north.

Meanwhile associated surface low over South Dakota this morning will deepen through
the day as it migrates eastward toward the western Great Lakes region and
drags attendant cold front into the Central Plains. Gfslamp meteograms
have been consistent showing the leading edge of the boundary moving
through the Oma metropolitan during the late afternoon hours. Brunt of strong cold air advection
arrives on Thursday with a noticeable drop in temperatures with highs
only in the upper 40s/low 50s.

Thursday night/Fri...precipitation will again be possible and focused over the
northern County Warning Area where moderate qg forcing is expected to set up. May even
see mix of rain/snow per BUFKIT. Given weak moisture...small probability of precipitation
still best fit for now.



Long term...(friday night through tuesday)
issued at 412 am CDT Wednesday Apr 16 2014

Global models are consistent in moving a trough across The Rockies
and into the Central Plains this weekend. The models diverge to some
degree as to how quickly to move the trough out of the area with
little in the way of an upstream kicker. The 00z European model (ecmwf) is holding
onto this trough into the day on Monday as the slowest solution.
Ahead of the system modified Gulf air will be advancing northward on
Saturday. Most of the day on Saturday should be dry but a cold front
will move into northeast Nebraska by afternoon and this could be the
impetus of scattered showers and isolated thunderstorms by afternoon.
As larger-scale forcing increases on Saturday night...along with
stronger low level warm-air advection we should see an increase in
the areal extent of the precipitation...and likely probability of precipitation appear warranted at
this time. The 00z GFS/Gem would then shift this forcing/precipitation
south of the area by Sunday night while the European model (ecmwf) would continue
some threat into Monday. Although the slower solution of the European model (ecmwf)
isn't out of the question...given the limited support will continue with
a dry forecast for Sunday night through Tuesday.

Temperatures will warm into the 70s for most areas on Saturday ahead
of the cold front...but with the precipitation and cold air advection on Sunday
temperatures will likely hold in the 60s. Temperatures should be on
the increase for Monday/Tuesday as a western US ridge develops east into
the central US.

&&

Aviation...(06z tafs for kofk...klnk and koma.)
Issued at 1148 PM CDT Tuesday Apr 15 2014

Winds will be the primary concern this taf cycle. South to southeast
winds at 12 to 20 kts sustained will continue overnight. Low
level wind shear was mentioned at all three sites as profilers
and forecasts showing a low level jet of 50 to 60kts through 14z.
Stronger wind speeds will mix down in the morning with sustained
winds of 18 to 25kts sustained. A cold front will turn the winds
to the southwest and then the northwest Wednesday. Forecast
soundings show the potential for instability showers Wednesday
afternoon...but did not mention at this time.



&&

Fire weather...
issued at 412 am CDT Wednesday Apr 16 2014

The combination southerly winds gusting around 45 miles per hour along with
minimum relative humidity values around 20 percent for several hours will create
conditions favorable for rapid fire growth. Do not attempt any
type of outdoor burning during this time.

&&

Oax watches/warnings/advisories...
NE...red flag warning from 10 am this morning to 6 PM CDT this
evening for nez045-051>053-065>068-078-088>093.

Wind Advisory from 10 am this morning to 6 PM CDT this evening
for nez045-052-053-067-068-090>093.

Iowa...red flag warning from 10 am this morning to 6 PM CDT this
evening for iaz055-056-069-079-080-090-091.

Wind Advisory from 10 am this morning to 6 PM CDT this evening
for iaz055-056-069-079-080-090-091.

&&

$$

Short term...Dee
long term...boustead
aviation...zapotocny
fire weather...Dee