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Area forecast discussion 
National Weather Service Des Moines Iowa
1141 PM CDT sun Apr 26 2015

Short term /tonight/...
issued at 324 PM CDT sun Apr 26 2015

The quiet weather from today will persist into tonight as surface
ridging across the upper Midwest remains near Iowa. Surface winds
will be light overnight along with clear skies which will enhance
radiational cooling. Temperatures will fall to near freezing once
again in the far north and northeast toward daybreak and have
included patchy frost in the forecast for those locations. Have
also included some in favored Nishna valleys in the west as well.
May see some patchy fog toward daybreak given the light winds and
recent rainfall...especially in favored low lying areas and river

Long term /Monday through Sunday/...
issued at 324 PM CDT sun Apr 26 2015

High pressure will dominate the region from Monday into Tuesday
resulting in nearly clear skies and dry weather. Continued the
trend of lowering dewpoints during the daytime hours given the
trends seen today...but with light wind speeds and rapid green up
do not anticipate this will cause any fire weather issues. On
Tuesday and Tuesday night a weak low pressure trough will move
over Iowa. While any cold air advection associated with this
feature is negligible it may provide enough lift for some clouds
and even light rain...however forecast soundings indicate a
notable lack of moisture available so have continued to keep rain
mention out of the forecast. The European model (ecmwf) continues to become slowly
more bullish with its quantitative precipitation forecast during this time...relatively
speaking...but it will be hard to get more than glorified
sprinkles so will hold off and reassess for the next couple of
days. If any rain did occur it would be of little to no impact in
any event.

From Wednesday through Thursday a large 500 mb ridge will build
across the Midwest...reflected by a surface ridge that will result
in light winds and mostly clear skies once again. This should
allow the airmass in place to modify...resulting in a slow but
steady warming trend to end the week. Things get a bit more
complicated toward this weekend and into early next week. A
pattern shift will begin around Friday as a compact but fairly
vigorous 500 mb shortwave rockets eastward along the U.S./Canada
border and flattens out the aforementioned ridge over the Midwest.
This will usher in a more zonal flow over our region for the
remainder of the forecast period and beyond. Within this regime it
is expected that the warming trend will continue but chances for
showers and thunderstorms will return. There is little detail to
add regarding the timing of potential precipitation at this
range...but will maintain 20 to 30 probability of precipitation around the weekend to
account for the generally more active weather pattern set to


issued at 1140 PM CDT sun Apr 26 2015

VFR conditions through the period. Winds light and variable
overnight becoming northeast 10 to 15 knots on Monday.


Dmx watches/warnings/advisories...


Short term...cogil
long term...Lee

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