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Area forecast discussion 
National Weather Service Hastings NE
303 PM CDT Wednesday Apr 16 2014

Short term...(this evening through thursday)
issued at 302 PM CDT Wednesday Apr 16 2014

Most areas will remain dry and cooler than normal through Thursday.
The strong winds of this afternoon will gradually slacken off during
the evening and overnight hours as the pressure gradient relaxes.

The remainder of the afternoon into tonight...the surface low will track
east northeast from the Nebraska/Iowa border this afternoon...into
Wisconsin by sunrise on Thursday. The quick movement of this system
away from US will allow the pressure gradient force to also rapidly
decrease and thus our wind speeds will die down through the evening
and overnight hours. The wind direction will remain generally
northwesterly...but could shift closer to due north by dawn.
Temperatures are a challenge tonight given uncertainty with regard
to cloud cover. The decreasing wind should allow temperatures to
fall off and colder air is advecting in behind todays cold front.
However...scattered to broken cloud cover may act as a blanket
helping to hold temperatures up a bit. Will stick pretty close to
allblend model guidance for lows tonight...which would result in
below freezing temperatures for all Nebraska zones and a few of our
northern most Kansas locations. Temperatures may not be as uniform
as forecast though as any areas that can clear out better may dip
colder than our going forecast...while areas that hold more clouds
could be a touch warmer than our forecast. Normal lows for this time
of year are now in the upper we are expecting lows to be
around 10 degrees cooler than normal.

Thursday...high temperatures will likely be cooler tomorrow than
they were today for most areas along and south of Interstate 80 due
to the colder air moving into place behind todays cold front.
However...there will be much less wind and thus it might actually
feel nicer for many areas tomorrow. The light wind will still be out
of the north in the morning...but expect the wind to shift to
southeast by afternoon as the high slides off to our east and we
begin to experience that warming return flow behind the departing
high. Normal highs are now in the middle 60s and we should be well
short of that with most areas seeing highs around the middle 50s. The
light wind will be a welcomed change. A weak storm system will track
off to our south across Kansas and is not expected to impact our
forecast area.

Long term...(thursday night through wednesday)
issued at 302 PM CDT Wednesday Apr 16 2014

Primary forecast concern continues to lie with weekend precipitation

Looking at Thursday night through Friday night...hasnt been a lot of
changes in the latest run of models...with the start of the period
showing upper level northwesterly flow across the plains...with
ridging in between a departing trough axis and an area of low
pressure moving toward the Southern California coast. Dry conditions remain in
the this ridge axis slides east out of The Rockies and
onto the plains...and should be right overhead by Friday evening. At
the surface...expecting there to be increasing southerly winds
during the daytime hours on the pressure gradient
tightens across the region...thanks to low pressure approaching from
the west. Speeds in the 15 to 25 miles per hour range currently forecast.
Still looking at a nice bump up in temperatures from Thursday...but overall
no notable changes were made...with highs sitting in the upper 60s
to lower 70s.

Most interesting timeframe of the long term period still looking to
be this thunderstorm chances make their way back into
the region. By 12z Saturday...models in good agreement showing the
upper level pattern having transitioned to southwesterly
that above mentioned West Coast low has moved inland...and is
roughly located over western Arizona. There is another area of upper level
low pressure...located over central Canada...which will slide east
through the day. This disturbance will push a surface frontal
boundary into western portions of the County Warning Area during the day...while also is
affected by an area of low pressure becoming better organized over
southern portions of the Colorado/Kansas border. While some scattered precipitation a
possibility through the first half of the day...chances will be
ramping up through the afternoon and evening hours...especially along that
surface front as the larger scale lift increases with the arrival of
that upper level disturbance. Models differ on how widespread and
heavy quantitative precipitation forecast fields are Post 00z...with some increase expected with the
increase of the low level jet. Model depicted instability continues to
vary...and deeper layer shear is on the weaker side...but cant rule
out some at least strong thunderstorms...which at this point looks
to primarily affect the southeastern half of the County Warning Area. For Easter
Sunday...the main upper level trough axis is expected to push
through the region...and the better chances for precipitation remain over
southeastern portion of the County Warning Area...and activity should diminish through the
day. Not quite buying into the latest run of the European model (ecmwf)...which is
showing a closed middle/upper level circulation developing late in the
day Sunday...thus resulting in more quantitative precipitation forecast and a much slower departure.
The 12z GFS/Gem keep things open and more kept
forecast trended that way. Will see how upcoming runs trend before
inserting another period of probability of precipitation Sunday night.

Looking ahead the upcoming start of the work week...the forecast for
Monday/Tuesday remain dry...with upper level ridging developing once again
over The Rockies/High Plains in between systems...and gradually
making its way onto the plains. More uncertainty arrives in the
forecast as we get toward a notable upper level low
pressure system moves onto/develops over the Pacific northwest/northern rockies
region. Possible a shortwave piece of energy out ahead of this
system could bring some precipitation chances to the County Warning Area on Wednesday...and have
slight chance probability of precipitation going.

As far as temperatures go...the ultimate amount of clouds/precipitation in
the area will obviously affect things this weekend...especially
Sunday...but current forecast highs are in the upper 60s/middle 70s for
Saturday ahead of the front...with middle 60s on Sunday. Expecting
highs to climb back into the middle and possibly upper 70s for


Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 1255 PM CDT Wednesday Apr 16 2014

As of 18z...the cold front was in the process of tracking through
kgri and the wind direction was shifting to northwesterly. The
wind will quickly pick up early this afternoon with some gusts to
over 30 kts. The wind will remain strong until after sunset and
then will gradually die down through the evening and overnight
hours. The pressure gradient will continue to weaken on Thursday
with the wind becoming light and primarily out of the north. A low
strato cumulus deck will continue to develop this afternoon...but
expect ceilings will primarily remain VFR although it is not out
of the realm of possibility that we see some MVFR ceilings prior
to sunset. The cloud deck may lower even further after dark...but
confidence in how low the ceilings will go tonight is low. Can
not rule out IFR ceilings tonight...but believe that MVFR and VFR
ceilings are more likely.


Gid watches/warnings/advisories...


Short term...wesely
long term...ado