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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
547 PM CST Monday Feb 8 2016

..aviation update...

issued at 253 PM CST Monday Feb 8 2016

18z surface data has an inferred low over Eastern Lake Superior with a
frontal boundary from the low to Chicago...and then west into
central Iowa. Dew points were in the single digits and teens from
the plains into the western Great Lakes with 20s across the Ohio


Short term...(this evening through tuesday)
issued at 253 PM CST Monday Feb 8 2016

What radar can see indicates the areal coverage in the snow is
decreasing. However...observations indicate area radars are likely
overshooting some of the light snow.

Light snow/flurries with embedded heavier snow showers will continue
through sunset. After sunset...very light snow/flurries are expected
to continue across most of the area with the better chances east of
the Mississippi. In fact...with another upper level disturbance
dropping down late tonight there may be a resurgence in snow shower
activity east of a Dubuque to Kewanee line.

Snowfall accumulations late this afternoon and tonight should be
under an inch. However...very localized amounts over an inch are
possible where snow showers persist for any period of time.

On Tuesday...light snow/flurries will continue as even colder air
aloft moves into the area. Show showers should redevelop by late
morning and continue through the afternoon east of the Mississippi.
As the upper level disturbance shifts further east on Tuesday the
light snow/flurry activity should slowly end across the western half
of the area.

Snowfall on Tuesday should again be under an inch.

Temperatures on Tuesday will be well below normal.

Long term...(tuesday night through monday)
issued at 253 PM CST Monday Feb 8 2016

Main forecast concern for the long term are a series of clippers
that will affect the area through the period. Light snow is
possible for each of the systems...however the exact placement of
the snowfall will be in question due to the small nature of the
systems. Overall the flow leads to cooler temperatures then some
moderation in the temperatures late in the period towards warmer values.

Wednesday...differences in the timing and the location of the
clipper are leading to low confidence in the forecast for Wednesday.
At this time....will use a blend between the solutions and go with a
schc snow for Wednesday afternoon and Thursday am. Quick moving system will
likely lead to less than an inch of snow across the along the
Highway 34 corridor.

Another clipper is forecast to move into the area for Friday. At
this time...there are still discrepancies between timing and
location of the 500 mb wave. As a result will stay with the superblend
forecast. A surface high will build into the area this weekend
leading to cold temperatures...but quiet weather for the weekend. At
this time there appears to be a warm up late in the period at the
beginning of next week.


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 541 PM CST Monday Feb 8 2016

Mostly MVFR conditions to continue. Low clouds associated with a large
and slow moving upper low over the western Great Lakes will begin to
slowly dissipate Tuesday afternoon. Ceilings will be generally 1-3k above ground level
at all the terminals with episodes of flurries or very light snow with
visibilities 3-6 miles...this evening and slowly ending by middle day Tuesday.
Skies may become fair by 12/00z if subsidence kicks in but have as broken
at all terminals in the afternoon hours. Northwest winds will continue
mainly in the 15 to 25 knots range.


Dvn watches/warnings/advisories...


short term...08
long term...Gibbs

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