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Area forecast discussion
National Weather Service Omaha/valley NE
541 PM CST Sat Feb 25 2017

Short term...(tonight through tuesday)
issued at 305 PM CST Sat Feb 25 2017

Temperatures will be the main forecast concern through Monday,
then will deal with precipitation chance and precipitation type
issues from Monday afternoon into Tuesday morning. Snowcover will
have some impact the next few days.

A fast moving shortwave trough will move through the region
overnight, producing some variable cloudiness. At the surface,
south/southwest low level winds should help keep temperatures up a
bit compared to last night. Lows are expected to range from teens
north to 20s south. Dry weather should be the rule from Sunday
through Sunday night. Relatively weak mixing on Sunday should
limit highs to the mid and upper 30s in the northern part of the
forecast area where snow is the deepest, but allow for highs in
the 40s south.

Low level southerly flow/isentropic upglide will increase Monday
as low pressure strengthens over eastern Colorado. The 12z runs
of the GFS, European model (ecmwf) and Canadian models all suggest some light rain
will be possible Monday afternoon for parts of eastern Nebraska.
Chances will increase a bit for Monday night as the surface low
tracks quickly northeast toward southeast Nebraska. A colder air
moves in, rain should mix with and change to snow. Thermal
profiles suggest a that a mixture of rain/snow/sleet/freezing is
possible, especially the northwest half of the forecast area. Will
go with that for now and fine tune as we get closer to that time.
Right now will have no mention of precipitation Tuesday

Long term...(tuesday night through saturday)
issued at 305 PM CST Sat Feb 25 2017

It appears that a stronger shortwave will move out across parts of
our area Tuesday night, mainly southeast Nebraska into southwest
Iowa. Forcing, including mid level frontogenesis, appears adequate
for some 0.10 to 0.25 precipitation amounts. Generally thought
the quantitative precipitation forecast from the 12z GFS was too high and that its amounts of over
0.10 were too far north. Favored more of a blend of the European model (ecmwf) and
Canadian models. Initially very early Tuesday evening, most of
the precipitation should be rain, but that will change to snow as
the cold air deepens. Its a bit early, but some snow accumulation
does seem possible Tuesday night and possibly into Wednesday

The rest of the period from Wednesday afternoon into Saturday
looks dry. High temperatures should slowly moderate from Wednesday
through Friday, then Jump Up into the 50s and lower 60s Saturday.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 540 PM CST Sat Feb 25 2017

VFR conditions are forecast through Sunday afternoon with only
scattered to broken mid and high clouds expected. South winds near
10kt will turn westerly Sunday.


Oax watches/warnings/advisories...


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