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Area forecast discussion 
National Weather Service Des Moines Iowa
642 PM CDT Monday Jul 28 2014

Short term /tonight/...
issued at 340 PM CDT Monday Jul 28 2014

Main issues will be early in the forecast with a few showers
passing through central Iowa. This activity will continue to sink
southward and dissipate this evening as heating subsides and weak
shortwave passes to the southeast. Extensive cumulus field will also
diminish with loss of daytime heating and drier air moving into
the state. With high pressure pushing into the Missouri River
valley...the pressure gradient will remain rather loose with winds
staying light overnight. Temperatures to hold well below normal
and with clearing skies and light winds...readings to be below
guidance in favored areas of northern Iowa as well as the Nishna
valleys in west central Iowa.

Long term /Tuesday through Monday/...
issued at 340 PM CDT Monday Jul 28 2014

Below normal temperatures continue to be the main forecast
concern during the extended period. Surface high pressure and
northwest flow aloft will dominate the weather pattern through the
end of the work week and into the weekend. A few ripples in the
northwest flow aloft this week will mainly reinforce the cool
temperatures. The GFS shows a bit stronger shortwave than the
European model (ecmwf)/NAM to cut across eastern Iowa on Tuesday afternoon. May see
a few spotty sprinkles in the northeast...but have low confidence
with much measurable precipitation at this time due to the lack of moisture
available. Left forecast dry for now but did increase cloud cover
past 18z Tuesday.

Next significant system comes through on Friday into Friday night.
Models have been generally consistent with bringing a shortwave
across the state during the aforementioned time frame and kept
isolated thunder mentioned on Friday. GFS wants to bring in fairly
strong cold front and trough through the region Sunday night into
Monday...but European model (ecmwf) is about a day late. Regardless...seems Monday
time frame is the best potential for any significant accumulating


issued at 642 PM CDT Monday Jul 28 2014

VFR ceilings will become scattered by 02z and winds will diminish as
high pressure builds in. Some cumulus will develop in the late
morning/afternoon but should be generally less in coverage than what
we have seen the last couple of days.


Dmx watches/warnings/advisories...none.



Short term...cogil
long term...podrazik

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