Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus63 koax 241731 
afdoax

Area forecast discussion
National Weather Service Omaha/valley NE
1231 PM CDT Fri Mar 24 2017

Short term...(today through sunday)
issued at 345 am CDT Fri Mar 24 2017

Intense mid-level cyclone associated with 150 M 500 mb height falls
this evening was located over southeast Colorado early this morning. Broad zone
of ascent associated with strong low- to mid-level thermal
advection was ongoing to the northeast of the cyclone from the
Central Plains to the upper MS River Valley. The ongoing forcing
for ascent is expected to weaken this morning as the mid-level dry
slot works northeast toward the area. We will continue with some
high pops initially in the northwest County Warning Area close to the mid-level
deformation zone as well in the southeast County Warning Area associated with
ascent with the veering low-level jet.

Models are in fair agreement today in the upper level cyclone
moving east across southern Kansas/northern OK and into eastern MO by
Saturday night. As the dry slot works into the southern County Warning Area the
700-500 mb lapse rates will steepen as 500 mb cold pocket works
toward the southern County Warning Area. This will combine with existing low-
level moisture to increase instability in a zone from the 850 mb
front south into KS/MO. As temperatures ahead of the cold front
increase to around 70, and forced ascent associated with 700-400
cdpva becomes juxtaposed over the southern County Warning Area we will likely see
isolated to scattered convection develop. Instability is fairly
weak for late March and the wind profile is not overly favorable
for severe, but some small hail appears possible given the cold
temperatures aloft. Otherwise we expect frontogenesis to increase
over the northwest County Warning Area within the developing deformation zone
where steady light to moderate rainfall is expected. The
deformation band will further expand and include a good part of
the rest of the County Warning Area tonight and into most of Saturday before
shifting east with a dry Sunday expected.

Temperatures today are problematic with outflow associated with
the ongoing convection now pushing south of i80. We are still
observing 2-3 mb 3-hr pressure rises behind this outflow and thus
it may continue to push south a bit before stalling. There will
be a strong temperature contrast across this boundary today
somewhere in the County Warning Area with highs near or slight better than 70 to
the south of it and highs in the 40s in the northwest County Warning Area. This
boundary should push to the south tonight with much cooler air
expected into the weekend.

Long term...(sunday night through thursday)
issued at 345 am CDT Fri Mar 24 2017

The active weather appears to continue into the extended range of
the forecast. Another trough crossing the plains on Sunday night
into Monday will bring a chance of rainfall to mainly the southern
County Warning Area. After another short break another trough is expected toward
mid week, but models diverge significantly on the track of this
system with the GFS well south while the ec is much farther north.
Given these differences we will continue with some pops for mid
week with continued below normal temperatures.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1228 PM CDT Fri Mar 24 2017

Mainly MVFR ceilings are expected to persist through the taf
cycle, with periods of showers that may reduce visibilities to
around MVFR range. Kofk will see showers mainly this afternoon,
while koma/klnk should see rain this evening through Saturday
morning. Have removed thunder mention as sites are solidly in
cooler/stable airmass. Winds will remain northerly to north-
northeasterly at about 12-15kt, with some gusts possible at klnk
as they remain closer to the low pressure center.

&&

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

$$

National Weather Service Glossary of Abbreviations