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Area forecast discussion 
National Weather Service Hastings NE
328 PM CST Tuesday Nov 25 2014

Short term...(this evening through wednesday)
issued at 321 PM CST Tuesday Nov 25 2014

Focus is on impacts with the passage of clipper and an associated
cold frontal boundary. A 160kt 300 mb jet will dive south and move
across the plains tonight driving a clipper system from the Dakotas
southeast across the Dakotas into eastern Nebraska/Kansas tonight/early
Wednesday. An associated cold frontal boundary will sweep
southeast across our region ushering in colder air aboard gusty northwest

For precipitation this evening/early tonight...models are still hit
or miss about how widespread the activity will be. The WRF remains
the most robust with development but in general ensemble models
suggest decent chances for another light precipitation event especially for our
northern and eastern counties. In the frontogenetic forcing and
dynamics associated with the jet/clipper...chances for rain showers
increase toward 00z and continue through the evening/first part of the
night before diminishing behind the wave by daybreak Wednesday.
Have kept precipitation type as liquid into the first part of the
evening...then as cold air deepens behind the front...a rain and
snow mix or brief change to snow cannot be ruled out. Ensemble data
indicates snowfall amounts would remain under one tenth of an inch
so do not expect any accumulation at this time.

The next concern is the potential for noticeably strong winds
tonight with frontal passage. Models indicate pressure rises of 1 to 3mb
initially overnight with another round of pressure rises of 2 to
4mb Wednesday morning in between the surface low and a building surface
ridge. Model forecast soundings indicate mixing near or just below
850 mb with wind speeds at the top of the layer between 35 and 45kts.
Given this...expect winds to increase by 06z...remain strong/gusty
through the night and during the day on Wednesday before subsiding
toward evening.

Winds should help hold up temperatures tonight...but in cold air advection
Wednesday...readings are expected to average in the 30s/low 40s

Long term...(wednesday night through tuesday)
issued at 321 PM CST Tuesday Nov 25 2014

Primary forecast concern lies with temperatures.

Has not been much change overall with the pattern to start off the
long term period...with troughing moving through the Great
Lakes/Midwest regions...and a ridge axis extending north along the
West Coast. See little change through the overnight hours Wednesday
night...models continue to show a strong upper level jet streak
nosing in from the northwest...with the strongest corridor sliding further
east/NE of the County Warning Area. Some models hint at the potential for a few
flurries to come close to the northwestern portions of the County Warning Area...closer to
that jet streak...but with most models keeping the atmosphere dry
will continue to keep out any mention. As we get into the daytime
Thursday...good agreement showing that while the upper level ridging
is sliding is losing another system moves
into the Pacific northwest region. At the surface...the period starts out with
a ridge axis extending south through the plains from high pressure
centered over the ND/Canadian border. Winds start out light...but
already by midday Thursday...southerly winds have returned as the
County Warning Area gets set up between high pressure just east of the Missouri
River and a trough of low pressure over the High Plains. So
Thanksgiving day looks to be good for traveling...dry
conditions...variable sky cover...southerly winds peaking in the 10
to 15 miles per hour range. As far as temperatures go...continue to expect a
warming trend from Wednesday...and trended highs toward the mav highs in the middle 30s in the NE to lower 50s in the

Getting to Friday and the upcoming weekend...models continue to show
the upper level pattern transitioning to more zonal flow with an area of low pressure becomes better organized just off
the West Coast. Still looking at dry conditions through the
weekend...models just not showing much in the way of disturbances
moving through the region. Friday and Saturday will continue the
trend from Thursday of a warming air mass pushing further east onto
the plains...though there is a bit of uncertainty with Saturday. An
upper level trough axis over the Pacific northwest early on Saturday will be
pushing east into the northern rockies through the day...and an
accompanying surface cold front will be on the move toward the County Warning Area.
Ahead of the front...downsloping west/SW winds with the warmer air in
place is expected to bring highs in the in the 50s/60s for Friday.
For Saturday...that cold front is becoming more of a
concern...especially if the GFS is right. Compared to 24 hours ago
when the ec/GFS werent in too bad of agreement...the GFS is more
aggressive with the push of the front/colder air...and thus is quite
a bit colder for highs. While the current forecast is not quite as
high as the European model (ecmwf) and Gem suggest is possible...not going to buy
full in to the GFS until it has some more model still
have 50s/60s in place for Saturday. Now highs on Sunday are solidly
affected by the front...which looks to push through the County Warning Area Sat
night/Sun morning...and could be 25 or so degrees colder than Sat in
the low 20s to low 30s.

The dry forecast continues on into the first part of the next work
week...with upper level flow transitioning to more southwesterly
flow as a trough axis digs south over the West Coast. This will
make for a short stay of that colder air mass that builds in behind
the front on Sunday...and while highs on Monday look to be stuck in
the 30s...temperatures for Tuesday are forecast to push back into the


Aviation...(for the 18z kgri/kear tafs through 18z Wednesday afternoon)
issued at 1135 am CST Tuesday Nov 25 2014

The weather will undergo changes during the taf period with a
passage of a cold frontal boundary and an upper level disturbance.
Cloud cover will increase and thicken today/tonight and chances for
rain showers increase for the evening hours. Northwest winds increase and
will be strong/gusty behind the cold front with gusts over 30kt
expected. The strong winds will increase during the overnight
hours and remain strong/gusty on Wednesday.


Gid watches/warnings/advisories...



Short term...Fay
long term...adp

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