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Area forecast discussion 
National Weather Service Omaha/valley NE
611 PM CDT Thursday Aug 28 2014

Short term...(tonight through sunday)
issued at 308 PM CDT Thursday Aug 28 2014

The main concern continues to be with convective potential through
Friday and then severe weather chances on Sunday.

The upper level storm system that brought the wet weather to the
region over the last couple of days continues to spin over eastern Colorado.
This will continue to make progress across Nebraska/Iowa over the next 36
hours. Weak surface low over central Nebraska associated with the upper level
system will track eastward allowing a weak boundary to move into eastern
Nebraska by Friday. Although a good deal of clouds remains the forecast area this
afternoon the latest objective analysis indicates that instability is
increasing with around 1000-1500 j/kg of MLCAPE. Short term models
indicate that the large-scale forcing for ascent will increase later
this evening as 700-300 mb DPVA increases across the County Warning Area. This
along with the instability and weak capping should allow for some
increase in thunderstorms and rain coverage through the evening. We do not expect
the coverage of rainfall that we saw the last couple of nights but
still high chance to likely probability of precipitation appear warranted in the far south
and also closer to the low in the north. We will likely see an
decrease in activity after midnight tonight as we see a loss of
instability...with only spotty light showers possible given the
continued forcing and moist atmosphere.

The upper level low will cross the forecast area during the day on Friday and
with some surface heating in the morning we should see a good increase
in showers and isolated thunderstorms and rain during the middle to late morning over the
northern and eastern 2/3 of the forecast area under the upper level low and near the
surface boundary. The boundary and associated upper level low will
track eastward by Friday night with rain chances ending from west to east by or
shortly after midnight. This should lead to quiet weather on Sat
and a return to near normal temperatures.

The break in active weather will be short-lived however as a
stronger more progressive trough drops into the northern rockies Sat
night. This will allow for a cold front to track eastward across Nebraska
during the day on Sunday. Decent moisture will remain in place and
with an increasing wind field aloft we could see a favorable set-
up for severe weather in the County Warning Area during the afternoon and evening.

Long term...(sunday night through thursday)
issued at 308 PM CDT Thursday Aug 28 2014

Thunderstorms will likely continue into Sun night but once the cold front
passes the extended period of the forecast looks pretty quiet.
Temperatures are likely be near seasonable normals with highs
around 80s and lows in the 60s.


Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 608 PM CDT Thursday Aug 28 2014

VFR conditions early in the taf period. Developing convection and
impact on taf sites is the main problem. Believe best chances will
be at klnk 07-11z and koma 08-12z. Should see ceilings become MVFR
through the night...with temporary IFR conditions at kofk. Should
be back to MVFR by 16z...and could see additional thunderstorm
development at koma 16-22z tomorrow.


Oax watches/warnings/advisories...


Short term...boustead
long term...boustead

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