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Area forecast discussion 
National Weather Service Omaha/valley NE
628 PM CDT Sat Oct 25 2014

Short term...(tonight through tuesday)
issued at 320 PM CDT Sat Oct 25 2014

Short term forecast concerns will be the return of deeper
moisture tonight and low clouds/fog development.

Seasonably strong 130-150kt upper level jets were located over the
Pacific northwest and north of the Great Lakes. These features were
associated with the 500 mb trough off the West Coast and attendant 130m+
height falls. In addition...there was a negatively tilted 500 mb trough
north of the upper Great Lakes. A broad 500 mb ridge was situated over
The Rockies and central part of the country. At 850 mb...the thermal
ridge was over the south Central Plains and the deep moisture
across southeast Oklahoma into the Tennessee River valley. Surface
high pressure prevailed across the region with sunshine and much
above normal temperatures in the 70s/80s. Records for this time of
year are in the upper 80s to around 90...so well below those
levels.

We had some dense fog that developed from Illinois into
Missouri...and spread into southern Iowa and southeast
Nebraska...where the surface dewpoints were high ahead of the
drier air.

At 20z...surface dewpoints varied from the lower 30s in the north
near the South Dakota border to the middle 50s just south of
Beatrice. Tonight and early Sunday...surface high pressure will
influence the area with dry air. Southwest flow aloft is forecast
to increase and 850 mb winds should be around 25 to 35kts. The high
resolution models do not go out far enough on Sunday. The
NAM/sref are more aggressive with the low level moisture than the
GFS. The rap is similiar to the NAM and is stronger with the
forcing.

As the surface warm front lifts north...there will be
isentropic lift and deeper moisture in the lower levels that will
favor stratus development tonight. Do mention areas of fog in the
southwest and patchy fog into the central zones/ there may be some
sprinkles or drizzle and depending on how long the low clouds hang
on...would affect temperatures. The mixing from Omaha north and
northeast is more questionable...thus have highs 70 to 75 with
warmer 75 to 80 degree temperatures in the south for Sunday.

A cool front moves through Sunday night and there may be some Post
frontal showers Monday. Highs Monday in the 60s and 70s. Breezy
northwest winds are forecast for Tuesday with highs in the 50s.

Long term...(tuesday night through saturday)
issued at 320 PM CDT Sat Oct 25 2014

The extended forecast is generally dry. A weak front passes
through Wednesday night with ridging over The Rockies for the rest
of the extended. The ec does bring the ridging east...however the
GFS is slower with this...thus the cooler highs in the 50s for
Friday and Saturday compared to the 60s Wednesday and Thursday.

&&

Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 628 PM CDT Sat Oct 25 2014

Clouds will be on the increase later tonight. Ceilings may drop
into the MVFR category and there may also be some fog. Most likely
area for fog with visibility under 3 miles is klnk. As winds aloft
increase at around 1000 feet...some low level wind shear will
develop late tonight and last into middle morning Sunday.

&&

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

$$

Short term...zapotocny
long term...zapotocny
aviation...Miller

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