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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
525 am CST sun Dec 28 2014

issued at 330 am CST sun Dec 28 2014

06z surface analysis has high pressure from the Southern Plains into the
western Great Lakes. An Arctic front ran from Western Lake
Superior...through central Minnesota and into southwest North
Dakota. Dew points were in the teens and 20s across the plains and
Great Lakes.


Short term...(today and tonight)
issued at 330 am CST sun Dec 28 2014

Quiet and dry conditions will be seen across the area today with
temperatures near normal. The Arctic front will continue moving
south during the day and enter the far north shortly after sunset.

Tonight the Arctic front will move through the area during the
evening hours with increasing clouds. After midnight a weak upper
level disturbance will start moving through the Midwest. The weak
forcing from this disturbance in combination with the limited
moisture from the Arctic front should generate some flurries and
possibly some very light snow north of I-80 and west of the
Mississippi just prior to sunrise Monday.

Long term...(monday through saturday)
issued at 330 am CST sun Dec 28 2014

The main forecast concerns in the long term period are temperatures
and associated wind chill impacts....then the possibility of a
storm late this week.

On Monday...a weak frontal boundary will push south through the
forecast area. The WRF is a bit more bullish with moisture
compared to other operational models...but may very well be
overdone. With the strong cold surge...occasional flurries are a
good bet...but the chances for measurable snow remain low. The
northwest could pick up a light dusting Monday morning...with the
south favored for very light accumulations Monday night.

Monday night through Wednesday night still looks to be the coldest
stretch of the long term period...with lows in the single digits
and teens...and highs in the teens/low 20s. Expect periods of sub
freezing wind chills...especially west of the Mississippi River.
Tuesday night will likely be the coldest night...and wind chill
values could approach the 20 below zero advisory criteria in the
far northwest.

Attention then turns to the potential for a storm system late this
week. The 28/00z operational GFS and Euro are now in decent
agreement...with the Euro a bit farther east...allowing colder air
to spread farther southeast through the forecast area. The GFS
surface low track would limit the more significant snow to the
northwest half of the forecast area. Taking both models at face
value...the ingredients are there for a significant snow event with
complications from strong winds. However...this system is still in
the 6 to 7 day time frame...and confidence remains low as the
models may be too fast in ejecting the closed 500 mb low out of the
southwest Continental U.S.. so for now...the best approach is to keep model
blend probability of precipitation in the chance category for Friday and Saturday. It may
be several days before we begin to get a good handle on the
eventual storm track.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 523 am CST sun Dec 28 2014

MVFR clouds have just exited kbrl so VFR conditions will now be
seen through 00z/29. After 00z/29 VFR conditions will continue but
an cold front will slowly move south through Iowa and northern
Illinois. Some flurries are possible at kcid just prior to sunrise


Dvn watches/warnings/advisories...


short term...08
long term...rp Kinney

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