Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
FXUS63 KOAX 012340

Area Forecast Discussion
National Weather Service Omaha/Valley NE
540 PM CST Thu Dec 1 2016

.SHORT TERM...(Tonight through Sunday)
Issued at 245 PM CST Thu Dec 1 2016

The primary forecast concerns in this period are precipitation
chances starting late Saturday afternoon through Saturday Night.
Cloud cover tonight into Friday morning is also a concern, since
it will affect temperatures.

Large scale pattern at 500 mb featured a closed low over the
northern part of the Ontario/Quebec border area and a couple of
shortwave troughs digging into the Rocky Mountain region. Our area
was in weak west/northwest flow. This pattern will be changing.

A trough will sharpen from eastern Montana into western Arizona
Friday morning and a closed low should form over southwest Arizona
by Friday evening. That closed low will strengthen and drop down
into Mexico Friday night and Saturday as a wave in the northern
part of the stream moves out across the northern and central parts
of the Plains. Models continue to show deeper moisture moving in
during the day Saturday, but generally hold off precipitation
development until Saturday night. This may need some refining as
we get closer. Precipitation type will initially be rain, but
then go to a mix and then light snow before ending. But amounts
with this system look very light. Amounts and chances look higher
to the south and east.

Skies will be clear to partly cloudy south and partly cloudy to
cloudy north tonight, but central parts of the forecast area will
see variable cloudiness. Generally went around or a little lower
than a blend of MOS where sky will be clear or partly cloudy.

We still expect high temperatures to moderate slightly on Friday
and then a bit more Saturday/Sunday.

.LONG TERM...(Sunday night through Thursday)
Issued at 245 PM CST Thu Dec 1 2016

The first part of this period should be mainly dry, from Sunday
night into Monday. We will continue to include precipitation
chances from Monday night into Wednesday. But, as with the past
several days, model consensus is poor. This means confidence on
any one model precipitation scenario is low. For example, the
12Z GFS shows less than 0.10 inches of total water equivalent
in our area, but the GFS ensemble mean shows over 0.25 inches.
The 00Z ECMWF was dry Monday night and Tuesday, it but showed
measurable snow Tuesday night and Wednesday. The 12Z ECMWF was not
available for viewing as of 2045Z.

Confidence remains higher (compared to precipitation details)
that it will turn colder next week, and the trend for below
normal temperatures could continue beyond Day 7. Bottom line,
there is some potential for rain and snow next week, but it is
way too early to talk about specific details or amounts.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 536 PM CST Thu Dec 1 2016

Area of MVFR cigs northeast Nebraska into western Iowa will be
slow to clear from south to north overnight. We will likely see
periods of VFR and MVFR conditions through 12Z at KOFK and KOMA
before clouds lift far enough north. Then VFR conditions are
forecast through Friday afternoon with generally light winds.




LONG TERM...Miller
AVIATION...Dergan is the U.S. government's official web portal to all federal, state and local government web resources and services.