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Area forecast discussion 
National Weather Service Omaha/valley NE
1243 PM CDT Friday Apr 18 2014

Short term...(today through sunday)
issued at 300 am CDT Friday Apr 18 2014

A more active pattern returns to the forecast area this
weekend...especially the latter West Coast short wave
energy interacts with increasing moisture.

However...before then temperatures are primary focus into
Saturday. Shortwave upper ridging over plains today will provide
warm advection as northern section of western U.S. Upper trough brings
falling pressures over Western Plains and gusty winds to the forecast area...especially
by afternoon. This in turn should bring an increased fire danger
to area this afternoon. Even though surface dewpoints could recover a
bit today...lowering them toward guidance did provide a period of
afternoon relative humidity values near 30 percent. Previous forecast temperatures looked
reasonable and were supported by BUFKIT soundings/model guidance.

Increasing low level jet could kick off a few high based showers
in northwestern zones Saturday morning as any energy on southern side of northern
stream trough interacts. that trough departs would
suspect better chances of any convection would hold off until
Saturday evening and especially Sat night as better moisture feeds
north and shortwave energy in southern stream trough begins to approach
region. Based on current forecasts of GFS/ECMWF...850 mb
moisture/instability is not quite as robust through Sat afternoon compared
to last Saturday so main action may wait for diurnal low level jet
strengthening. Thus adjusted probability of precipitation slightly to account for a
decreased chance many areas Sat afternoon/evening with best chances
generally focused after 06z. Boosted highs a bit southeastern zones ahead of
weak boundary as 850 mb temperatures continue to warm ahead of it.

Sunday becomes more tricky as southern stream upper trough begins
ejecting across mainly the Southern Plains but close enough to impact
forecast area. With 850 mb temperatures initially anyway pretty mild any breaks in
showers/thunderstorms could provide a quick boost into 70s while areas
with more clouds/precipitation could struggle to climb above 60/middle 60s. In
general focused cooler temperatures generally where GFS/European model (ecmwf) focused quantitative precipitation forecast
axis across western zones and also boosted probability of precipitation most areas...especially
parts of the west.

Long term...(sunday night through thursday)
issued at 300 am CDT Friday Apr 18 2014

Departing energy early Monday could provide southeastern zones with small
mostly morning probability of precipitation Monday otherwise it looks dry Monday afternoon through
Tuesday as short wave ridging ahead of next trough spreads across
the plains. Since this short wave trough could provide an active
middle/late week...removed small probability of precipitation with warm advection Tuesday.
Boosted readings a bit on Wednesday as that will be second day of warm
advection ahead of this next through although if warm advection
precipitation is widespread/lingers much of the day this would be in
error. Otherwise little/no changes to previous forecast/model blend
to temperatures. Decent rain/thunderstorm chances return in late Wednesday-Thursday
and possibly new day 7 period if upper trough closes northwest of area
per GFS instead of the more progressive European model (ecmwf). In any
event...looks like decent chance many areas could see decent 7
day rainfall totals with activity this weekend+next Wednesday/Thursday


Aviation...(18z tafs for kofk...klnk and koma.)
Issued at 1241 PM CDT Friday Apr 18 2014

VFR conditions will continue throughout the taf cycle. Morning
smoke and haze has mixed out and visibilities continue to improve
early this afternoon as southerly surface winds increase and gust to
near 30 kts. Passing high clouds are expected overnight. Have
introduced low level wind shear from near 06z through 15z or so as
a southwesterly low level jet increases.


Oax watches/warnings/advisories...


Short term...chermok
long term...chermok