Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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FXUS63 KOAX 180451

Area Forecast Discussion
National Weather Service Omaha/Valley NE
1151 PM CDT TUE MAY 17 2016

.SHORT TERM...(tonight through Friday)
Issued at 244 PM CDT Tue May 17 2016

While cool weather lingers, the pattern will be a bit warmer and
drier for the next few days.  Upper low at 12z was centered in the
UT/NV border area, with upper-level trough axis extending from
QB/ONT through the UP of MI and into MN. A secondary shortwave
around the trough was noted from western IA/eastern NE into central
KS, with another shortwave along the OK/TX border.  Quality 850mb
moisture was well south in TX, with a pocket of cool 850mb
temperatures aligned with the upper-level trough axis across the
Great Lakes and into the upper Midwest.  Surface high at 19Z was
centered in western NE, with another high centered in northern MN.
Dewpoint gradient across NE was from the mid-30s to around 50.

Main forecast concern for today through Friday is the potential for
intermittent, light, weakly forced showers essentially every
afternoon.  With cu field in western IA to southeast NE, a few light
showers were developing, and these should continue until around 00Z.
Drier weather should continue tonight into Wednesday morning, though
clouds may linger.  Think fog potential is lower early Wednesday
morning than it was early this morning, with northeasterly breeze
and lower dewpoints, but a few patches could still develop close to
the KS-NE border.  GFS remains the flag-bearer for developing
showers again on Wednesday afternoon, with other models more
reticent. Have continued to keep out mention, with a wary eye on
potential, as forcing is least evident on Wednesday.

An upper-level shortwave ejecting ahead of the digging Western US
upper low may provide a bit more impetus on Thursday evening,
especially with a more southerly 850mb fetch aiding moisture return.
Have continued to mention showers on Thursday evening and Thursday
night, but did remove thunder mention, as profiles look awfully
stable.  Potential for showers continues Friday.  Have mentioned
isolated thunder in the afternoon, though SREF progs would indicate
instability is still awfully hard to muster in eastern NE/western
IA.  Temperatures through the period should remain below normal,
with highs mainly in the 60s to around 70 and moderating slightly
each day, and lows trending upward from the 40s toward the 50s.

.LONG TERM...(Friday night through Tuesday)
Issued at 244 PM CDT Tue May 17 2016

Conditions turn warmer and more unsettled into early next week.  Of
any days in the period, Saturday has the best chance to stay dry,
with mid- and upper-level ridge passing overhead.  Continued
southerly low-level flow should finally allow some warming through
at least Monday and potentially into Tuesday.  Upper low is progged
to eject across the Plains sometime around Monday, bringing a
potential for convective development on Monday/Tuesday.  Timing and
speed of upper low are still quite a bit in question, leaving
uncertainty on where the highest convective potential will establish
itself.  That said, those days do bear watching for at least
thunderstorm potential and possibly strong to severe storms.


.AVIATION...(06Z TAFS for KOMA...KLNK...KOFK through 06Z Thursday)
Issued at 1145 PM CDT Tue May 17 2016

The main forecast concern overnight will be how extensive fog
development will be. Dewpoint spreads are large at koma and
klnk...however much higher dewpoints are just to the east and
south they are narrow with patchy fog already forming. Some of
the 00z models were less agressive with the fog...however did
mention a tempo mvfr vsby 10 to 14z. There are a few scattered mid
clouds otherwise vfr conditions. Forecast soundings show
instability cu again for Wednesday, so did mention some cigs


.OAX Watches/Warnings/Advisories...


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