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Area forecast discussion 
National Weather Service Hastings NE
508 PM CST Wednesday Nov 26 2014

Short term...(this evening through thursday)
issued at 324 PM CST Wednesday Nov 26 2014

A northwest flow pattern remained in place across the Central Plains
with an upper ridge over The Rockies and trough east of the Missouri
River. An upper jet was crossing the plains and a few flurries
developed in western Nebraska. Radar mosaic is picking up on the cloud
cover but with temperature/deep spreads around ten degrees...just not
expecting much for precipitation and have left things dry at this time.

A cold 1038mb surface high pressure system will build south from the
eastern Dakotas tonight. Under the influence of the cold
airmass...we are looking for overnight low temperatures to average
in the teens.

For Thanksgiving day...conditions will be dry and Thursday will be
the transition day between the cold conditions of today and a nice
warmup commencing Friday into the first part of the weekend. The
surface ridge axis will slide east during the day with return flow of
southerly winds setting up. The upper trough continues to move out
while warmer air/subtle ridging expands east of The Rockies. Temperatures
will begin to moderate with our western zones reaching the 40s to
near 50 for highs...while eastern areas will average in the upper
30s to near 40 degrees.

Long term...(thursday night through wednesday)
issued at 324 PM CST Wednesday Nov 26 2014

Primary forecast concern lies with temperatures.

Looking at Friday and Saturday...still looking at these two days
easily being the warmest of the entire period. Friday
morning...models are in good agreement showing northwesterly flow in
place across the plains...between troughing over the northestern Continental U.S. And
broad ridging over The Rockies. Through Saturday...there isnt any
significant change in the pattern...but it does gradually become more
zonal with time as an upper level disturbance moves into the Pacific northwest
region. The forecast remains a dry one...with no disturbances
expected to move through the area. The GFS has come around toward
the solution the European model (ecmwf) has been showing the past couple days with
the magnitude of warmer air building in from the west through this
period...with 850mb temperatures starting out Thursday evening in the single
digits above zero and increasing to the upper teens on Saturday. Surface
winds are expected to be west/southwesterly at around 10 to 15 miles per hour thanks to a
trough axis over the High Plains...and this downsloping component to
the wind combined with the warming temperatures is expected to make for a
couple real nice days. Fridays highs are currently forecast to reach
the middle 50s to middle 60s...with Saturday forecast to reach the middle 60s
cwa-wide. Do have one concern...models are in good agreement showing
a couple of 100+ knots upper level jet streaks moving through the
central/northern plains...with the center of the jet a touch further
south on Saturday /near the South Dakota/Nebraska border/ than on Friday. Issue
with this is how much cirrus/cloud cover may be around...especially across
northern portions of the County Warning Area. At this point...did bump up sky cover a
bit...but currently not expecting it to have an impact on
highs...but will be something for upcoming forecasts to consider.

The past few days the GFS had been pointing toward a quicker arrival
and passage of the surface cold front Sat/sun which will be pushed south
through the region by an upper level disturbance crossing the northern
Continental U.S.. there is better agreement among models today with the timing
of the front...with the wind shift to nearly winds pushing through
most of the County Warning Area by 12z Sunday...and the colder air building in behind
during the daytime hours. That colder airmass will linger around as
we get into Monday as well...but as we get into Tuesday...we see a
return of southerly winds with that airmass shifting off to the
east...and moderating temperatures. Sun/Monday highs are forecast to
top out in the 20s/30s...with Tuesday back in the upper 30s/40s. The
forecast sun through Tuesday remains dry...with lift associated with
that disturbance well to the north of the County Warning Area.

Confidence in the forecast for Wednesday /day 7/ is low due to
increasing spread between models solutions. At 12z Wednesday...both
the GFS/European model (ecmwf) have some kind of disturbance over the western Continental U.S....the
GFS is a bit further inland vs the European model (ecmwf) has the center of the low
off the coast. During the daytime hours...the GFS is much more
progressive with the system...moving it through The Rockies with
increasing lift resulting in quantitative precipitation forecast over the area. The European model (ecmwf) keeps the
low closed off and thus is slower with is movement...which ends up
with weak shortwave ridging moving into the area and staying dry. At
this point the forecast is trended toward the European model (ecmwf) and kept
dry...and will see how things trend in the coming days.

&&

Aviation...(for the 00z kgri/kear tafs through 00z Thursday evening)
issued at 459 PM CST Wednesday Nov 26 2014

Broken to overcast cirrus will persist for most of the night as we
will remain just east of an area of light snow occurring in
western Nebraska. Wind is quickly diminishing and will eventually
back more to the south as the night/Thursday. Sky cover should
scatter during the day Thursday.

&&

Gid watches/warnings/advisories...
NE...none.
Kansas...none.
&&

$$

Short term...Fay
long term...adp
aviation...heinlein

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