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Area forecast discussion 
National Weather Service Omaha/valley NE
619 am CDT Friday Mar 27 2015

Short term...(today through sunday)
issued at 325 am CDT Friday Mar 27 2015

Precipitation chances later today and into tonight...then again from late
Saturday night into Sunday are the primary forecast concerns.

Large scale middle tropospheric pattern at 00z last evening featured
a ridge extending from California up into western Canada and a
trough from the western Great Lakes into the Southern Plains. The
shortwave trough that brought some snow to parts of the local area
Thursday had moved down into Kansas and Missouri by late evening.
Some light accumulations around half an inch occurred in some of
the slightly higher terrain areas between kofk and kykn Thursday
afternoon.

For today...another shortwave trough in the northwest flow will be
dropping through the region. Used a blend of available model data
with a decent amount of weight given to the most recent 13 km rap
model runs. This suggests precipitation may reach into northeast Nebraska
by late afternoon. Forecast soundings differ on precipitation type...but
opted to include a mix of rain and snow showers at this time. The
NAM soundings suggest more of the precipitation will be rain while the rap
and hrrr are hinting at more snow. For now...expect little or no
snow accumulation during the daylight hours. Highs should be in
the 40s.

Moisture and lift will continue to push east/southeast across the
forecast area this evening and tonight. Tight thermal gradient
will still be in place at 850 mb...with coldest air in Iowa. Did
mention potential for some light accumulations mainly there
(western iowa) for tonight. Lows should reach the middle 20s to
around 30.

South/southeast low level winds will increase Saturday...as high
pressure moves off to the southeast and low pressure deepens over
the western Dakotas. Highs should reach mainly into the 60s.

Warm/moist advection will continue Saturday night with southerly
flow. Kept a small mention of showers for late Saturday night. A
cold front will be moving into northeast Nebraska by around 12z
Sunday. Increased probability of precipitation slightly for Sunday morning most areas and
for the southeast part of the forecast area Sunday afternoon. At
this time...it appears precipitation will be all liquid.

Long term...(sunday night through thursday)
issued at 325 am CDT Friday Mar 27 2015

The first part of this period should be mainly dry...at least
through Tuesday. Highs should be mostly in the 70s.

The next low pressure system of concern should move into the area
by Tuesday night. 00z runs of the GFS and European model (ecmwf) are fairly close
with frontal timing on Wednesday...so just kept a blend of the
output for now. Temperatures will be cooler after the frontal
passage with highs in the 60s Wednesday/Thursday...then possibly
down into the 50s by Friday.

&&

Aviation...(12z tafs for kofk...klnk and koma.)
Issued at 618 am CDT Friday Mar 27 2015

VFR conditions are expected through the forecast period.

&&

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

$$

Short term...Miller
long term...Miller
aviation...Dee

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