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Area forecast discussion 
National Weather Service quadrant cities Iowa Illinois
325 PM CST sun Feb 14 2016

issued at 149 PM CST sun Feb 14 2016

Analysis at 2 PM CST shows winter weather event is winding down
over the region with snow ending from west to east and should be
essentially done over all the area by 6 PM...if not sooner. Area
snow reports mostly in the 1 to 3 inch range with localized 3 to 4
inch amounts may be possible before ending south of Interstate 80.
Upstream energy supports clouds to hang around with isolated to
scattered flurries possible overnight. Southeast winds 10 to 20
miles per hour and temperatures around 20 degrees making for a cold day.
Upstream energy shows weak disturbances from Pacific northwest to
impact region again in 24 to 36 hours.


Short term...(tonight)
issued at 149 PM CST sun Feb 14 2016

Short term forecast confidence assessment...good or above average
with little sensible weather issues once any significant snow
ends before early evening.

Tonight...low clouds to limit mins to upper teens north to lower 20s
south with isolated flurries and possibly patchy light freezing drizzle
though this should be very light and have little or no impacts.

Long term...(monday through sunday)
issued at 149 PM CST sun Feb 14 2016

A weak upper level disturbance will move through the area on Monday.
If moisture/forcing is favorable...the possibility does exist for
some flurries or isolated snow showers across the south third of the
area. The rest of the area should remain dry. Attention then turns
to the next storm system.

The next clipper type system will move quickly through the area late
Monday night and Tuesday. The models have shifted the snow axis a
bit to the south and west from earlier runs. Thermal profiles
suggest all snow for this event. However...the far south may see a
rain/snow mix develop during the day on Tuesday that would lower
overall snowfall amounts there.

Very preliminary amounts suggest 1-2 inches with the heavier amounts
south of a Vinton Iowa to Monmouth Illinois line. Amounts under an inch are
possible north of a Dubuque Iowa to Princeton Illinois line. Both the Gem
and European model (ecmwf) are suggesting that this system could pass well to the
south and west of the area. If this occurs...the overall snow
amounts would be much lower.

Tuesday night dry conditions are expected as another Canadian high
pressure builds into the Midwest.

On Wednesday...a weak upper level disturbance will move through the
area. Moisture is limited but if enough forcing can act upon it
there may be a narrow band of light snow that develops and moves
across the area. If this band of snow does occur...any accumulations
would be a dusting at best.

Wednesday night on...

The model consensus has dry conditions Wednesday night and Thursday
as high pressure exits the Midwest and a storm system develops in
the plains. Temperatures should average above normal.

Thursday night and Friday the storm system will move through the
upper Midwest producing windy conditions. The better forcing and
moisture runs from Minnesota into Wisconsin. The model consensus has
mainly dry conditions Thursday night except in the Highway 20
corridor where there is a slight chance for rain. On Friday...the
model consensus has slight chance to chance probability of precipitation for light rain
across the area. Temperatures should average well above normal.

Friday night/Saturday...the model consensus has dry conditions for
the area as another high pressure quickly moves through the Midwest.
Temperatures will continue to average well above normal.

Saturday night into Sunday...another storm system will move through
the Midwest. There are disagreements among the models on where this
storm will track. Most solutions take the storm system south of the
area but others bring the storm system through the area. As a
result...the model consensus has slight chance to low chance probability of precipitation
across the south half of the area Saturday night and slight chance
probability of precipitation for the entire area on Sunday. Temperatures should average
above normal.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1117 am CST sun Feb 14 2016

General MVFR to IFR flying conditions to dominate the next 24 hours.
Areas of light snow to briefly moderate snow will end between 14/18z
and 15/00z at all the terminals. Trapped low level moisture will result
in low clouds with ceilings of at or below 1k above ground level to periods of 2-3k above ground level. Visibilities
will be 1-3 miles in snow...improving to at or above 5 miles most or all of
the time in light fog after 15/00z. Southeast winds will continue through
the period mostly in the 5 to 15 knots range.


Dvn watches/warnings/advisories...
Iowa...Winter Weather Advisory until 6 PM CST this evening for Benton-
Buchanan-Cedar-Clinton-Delaware-Des Moines-Dubuque-Henry Iowa-
Muscatine-Scott-Van Buren-Washington.

Illinois...Winter Weather Advisory until 6 PM CST this evening for Bureau-
Carroll-Hancock-Henderson-Henry Illinois-Jo Daviess-McDonough-
Mercer-Putnam-Rock Island-Stephenson-Warren-Whiteside.

MO...Winter Weather Advisory until 6 PM CST this evening for Clark-



short term...Nichols
long term...08

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