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Area forecast discussion 
National Weather Service Omaha/valley NE
544 PM CST sun Feb 7 2016

Short term...(tonight through wednesday)
issued at 250 PM CST sun Feb 7 2016

Winds and snow showers will continue to provide the primary forecast
challenges through Monday.

100+ knot 300 mb winds extended from northeast British Columbia down
into Wyoming at 12z on the backside of a digging middle tropospheric
trough. At 500 mb...12 hour height falls of up to 160 meters were
noted from Minnesota into southeast South Dakota...with 500 mb
temperatures of -30 c or colder. Modest cold air advection was
noted at both 700 mb and 850 mb from our area northwest into the
western Dakotas and eastern Montana. Surface analysis at 19z had
a low pressure center over the far northeast tip of Minnesota and
strong northwest flow from the Dakotas down into Nebraska. The
atmosphere was well mixed with temperatures mainly in the 30s to
middle 40s. Strongest winds noted so far have mostly been in western
South Dakota.

Showers...mainly snow showers...have been moving down from parts
of northeast Nebraska into east central Nebraska and western
Iowa. These could produce snow amounts up to around half an inch
or locally more but would be fairly scattered. Forecast soundings
continue to show fairly steep lapse rates below 700 mb and even
some very Low Cape values...thus the convective/showery nature of
the snow should continue at least this evening and probably for
part of the overnight.

Decided to extend the current Wind Advisory for about the
northwest half of the forecast area until noon Monday. Farther
south...we started a Wind Advisory starting later tonight and
will run that until late Monday afternoon. This may need some
adjustment this evening if strong winds push farther to the
southeast faster.

Regarding the blowing and drifting snow...there will be some...
especially drifting snow. At least for now...decided to handle
that with Special Weather Statement products. Web cams and reports up to this point
indicate that the snow is mainly drifting...and not being lofted
high enough to cause significant or widespread reductions to
visibility. Will still mention some blowing snow in our products

Winds will slowly decrease with snow chances dropping through
the day Monday as well as low pressure moves southeast and our
pressure gradient decreases. Temperatures are not expected to
recover much...with highs in the ranging from the middle 20s to
lower 30s.

No precipitation is expected Monday night...but we could see some light
snow try to move in from the northwest late Tuesday or Tuesday
night. At this time...decided to keep mention of light snow out
of the forecast for those periods with better forcing staying to
our west.

High temperatures Tuesday and Wednesday should range from 30s in some
of our western and southern zones to 20s in the northeast part of
the forecast area.

Long term...(wednesday night through sunday)
issued at 250 PM CST sun Feb 7 2016

Pattern looks similar to what is has the past few days. A middle
level ridge will be over the western United States and western
Canada at the start of this period...with a trough from Hudson
Bay down into the middle Atlantic. That ridge will build slowly
eastward with time...but remain to our west until Saturday. The
overall flow should become less meridional from Wednesday to

Models show some small chances for precipitation...but in general do not
agree on timing or locations. Will hold probability of precipitation below 15 percent for
now and adjust with later forecasts. Highs in this period will
likely remain in the 20s or 30s...depending on if any low level
cold air intrusions can push in from the north/northeast. At
least for now...expect some moderation by Sunday.


Aviation...(00z tafs for kofk...klnk and koma.)
Issued at 540 PM CST sun Feb 7 2016

Very windy conditions will rule the taf period as northwest to
north winds hold in the 25 to 40 knots range. A middle level low
pressure area could cause scattered snow showers through about
06z...with mainly MVFR visibilities expected...however brief IFR visibilities
are possible in snow and blowing snow. Ceilings will generally be VFR
near fl040...but will lower to MVFR by 06z and remain there until


Oax watches/warnings/advisories...
NE...Wind Advisory from 3 am to 5 PM CST Monday for nez045-051>053-

Wind Advisory until noon CST Monday for nez011-012-015>018-

Iowa...Wind Advisory from 3 am to 5 PM CST Monday for iaz055-056-069-

Wind Advisory until noon CST Monday for iaz043.



Short term...Miller
long term...Miller

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