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Area forecast discussion 
National Weather Service Des Moines Iowa
620 PM CDT Monday Apr 27 2015

Short term /tonight/...
issued at 205 PM CDT Monday Apr 27 2015

Little sensible weather overnight with state remaining under the
influence of surface ridge. Winds will be light overnight with
clear skies which should allow temperatures to drop a bit more than
guidance...especially favored areas of the north and the Nishna
valleys of the southwest.

Long term /Tuesday through Monday/...
issued at 205 PM CDT Monday Apr 27 2015

Forecast early this week has not changed much the last couple of
days...resulting in little to no change through the work week.
Guidance continues to come in cool and as a result have continued
to bump up temperatures a couple of degrees along with the neighbors
throughout the week.

Tuesday evening and into Wednesday will be highlighted by a weak
upper level trough moving through the region. The Euro has
consistently tried to hold onto precipitation the longest versus the
other models...but now all models dry out/remove precipitation before
moving into the state. Some cloud cover will result but should
quickly move out by Wednesday evening. For Thursday the region
will remain initially in northerly flow as low pressure system
moves south out of Canada and over the western Great Lakes and
eventually gets kicked east. As that system exits the region
southerly flow should return by late Thursday as an upper level
ridge slowly moves into its place and keeps the forecast dry.

By the end of Friday the upper level ridge flattens out and puts
US into zonal flow through the weekend and Monday. The models all
agree on the zonal flow...but strongly disagree on the timing and
strength of shortwaves moving through the system. In general...the
best consensus at this point is for a decent shot for storms both
Saturday and Sunday evening with moisture return and resulting
SBCAPE values over 2000 j/kg each day.

&&

Aviation...28/00z
issued at 620 PM CDT Monday Apr 27 2015

VFR conditions throughout the forecast period. Northerly to
northeasterly winds becoming light overnight and picking up again
a bit Tuesday. A cold front will just push into the northern County Warning Area
and impact kmcw toward late Tuesday.

&&

Dmx watches/warnings/advisories...none.

&&

$$

Short term...cogil
long term...Curtis
aviation...beerends

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