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Area forecast discussion 
National Weather Service Omaha/valley NE
522 PM CST Monday Nov 24 2014

Short term...(tonight through thursday)
issued at 243 PM CST Monday Nov 24 2014

Gusty northwest winds continue across the area...with stratus deck
and flurries pushing away to the east. Subjective 12z upper air
analysis indicates deepening upper-level trough...with 500mb trough
axis from the ont/mb border through western Iowa...and with height
falls up to 180m centered on the Great Lakes. Strong upper-level
jet was coming ashore in the Pacific northwest...with winds up to
around 165kt behind the trough. 850mb closed low was centered in
northern Michigan/eastern up of Michigan...with a finger of -10c or colder
temperatures extending through the Dakotas into eastern Nebraska. Ahead
of the 850mb front from the southeast into the Great Lakes/Ohio
River valley/mid-Atlantic...unusually warm and moist air and 50kt or
greater winds were noted. Surface low at 20z was centered in
northern Michigan...with tight pressure gradient westward through the

Main forecast concern is potential for light precipitation on
Tuesday night. In the meantime...gusty northwest winds should
slacken as pressure gradient loosens tonight...with return flow
tomorrow and temperatures warming into the 40s under middle-level warm
air advection. A fast-moving shortwave is prognosticated to descend out of
western Canada and across the Dakotas into Iowa on Tuesday
night...bringing a reinforcing shot of cold air as well as
precipitation. GFS is a wet outlier across the County Warning Area...with
European model (ecmwf)/NAM/Gem pushing most of the precipitation to the east of the
County Warning Area...leaving just the western fringe of light precipitation across
the area. Have played closer to the European model (ecmwf)/NAM/Gem solution...with
highest chances between 06-12z in the eastern County Warning Area. Any
precipitation that falls before midnight likely would fall as rain
or a mix with snow...then changing to snow...given above-freezing
temperatures expected to linger into the evening. Precipitation
then would likely be mostly or all snow after midnight as
temperatures fall...especially with cold air advection behind the
shortwave. Have kept snow/liquid ratios on the low side for
snowfall forecast...with current forecast snow amounts of about a
tenth or two in Nebraska and up to around a half inch in western Iowa.

Given fast-moving nature of clipper system...precipitation should
move out quickly on early Wednesday morning...leaving a cooler day.
Middle-level thermal gradient is prognosticated to sharpen on
Wednesday/Thursday as High Plains warm...with warm air advection
aiding temperature recovery. Any potential light precipitation
along that gradient looks to stay well west of the County Warning Area...with
Thanksgiving day remaining dry and on the cool side.

Long term...(thursday night through monday)
issued at 243 PM CST Monday Nov 24 2014

Temperatures will continue to trend warmer on Friday/Saturday...with
low-level southerly to westerly winds and flat upper-level flow. A
cold front is prognosticated to push southward out of the Dakotas around
Saturday night/Sunday...bringing cooler temperatures back at least
on Sunday. Precipitation is likely to develop on that front from
around Kansas/MO toward the Ohio River valley as it encounters moisture
returning from the Gulf...but frontal passage in this area is likely
to remain dry.


Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 519 PM CST Monday Nov 24 2014

VFR conditions are expected for much of the taf period. Gusty
northwest winds will continue to diminish overnight and turn to
the southwest by morning. Middle clouds will increase through the
day Tuesday but conditions are expected to remain VFR.


Oax watches/warnings/advisories...


Short term...Mayes
long term...Mayes

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