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Area forecast discussion 
National Weather Service Des Moines Iowa
552 PM CST Wednesday Feb 10 2016

Short term /tonight/...
issued at 354 PM CST Wednesday Feb 10 2016

Light snow coming to end across the east-
southeast with little additional accumulations anticipated. Forcing
is quickly diminishing and dry air as begun to make its way into the
northeast. Expecting cloud cover to clear or at least thin out
across the north and east...allowing for decent radiational cooling
to set up. Lowered minimum temperatures over the northeast closer to
the GFS and European model (ecmwf). Cloud deck looks to remain across the western to
southern portions of the forecast area and should keep temperatures
up closer the NAM.

Long term /Thursday through Wednesday/...
issued at 354 PM CST Wednesday Feb 10 2016

The progressive northwest flow will remain in place through
Saturday. The next system will arrive snow is expected to develop
over northwest Iowa by middle Thursday afternoon. This system will
not be as favorable for large dendritic growth with much of the
forcing occurring in a layer warmer than the peak dendritic growth
zone. Plates and columns will be more favorable with this
temperature and forcing regime thus snow ratios will be closer to
climatology around 12-13 to 1. Overall light amounts with
accumulations generally one inch or less.

A cold front will follow on Friday with gusty north winds
developing. Wind gusts over 30 miles per hour are likely. These winds will
create areas of blowing snow and may cause roadways to become snow
covered and icy again. An Arctic plunge arrives Friday night with
low temperatures of 5 to 15 below zero expected north of
Interstate 80 by Saturday morning along with wind chill values
near 30 below over far northern Iowa. Likely will require wind
chill headlines for Friday night into Saturday morning.

A stronger system will arrive Saturday night into Saturday as the
upper flow transitions to more zonal. An initial wave of light
snow is expected as Theta-E advection lifts across the state. This
will be followed by a more kinematically forced light snow on
Sunday. Certainly may have snowfall totals in excess of 3 inches
over parts of central Iowa between the two waves of snow. A
warming trend arrives next week with the zonal flow and warm
advection arriving. High temperatures in the 30s and 40s will be
common next week.


issued at 551 PM CST Wednesday Feb 10 2016

VFR conditions are in place across taf sites as light snow
departs to the southeast at 00z. Some MVFR ceilings linger...but confidence
in affecting any particular location is not great enough to
include at the moment...and that potential should wane into the
evening. Winds will diminish and becoming more northerly into the
night before becoming light from some southerly component in the
afternoon. Another round of light snow may approach kfod
late...but mainly affect taf sites just beyond the valid period.


Dmx watches/warnings/advisories...none.



Short term...podrazik
long term...donavon

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