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Area forecast discussion 
National Weather Service Des Moines Iowa
612 am CDT Friday Jul 11 2014

issued at 329 am CDT Friday Jul 11 2014

Low pressure and cold front will move across the region slowly
this weekend...passing south of Iowa on Sunday. A strong upper
level trough and polar high pressure will build in behind the
front bring much cooler than normal weather and several days of
dry weather for much of the work week.


Short term /today/...
issued at 329 am CDT Friday Jul 11 2014

Ongoing precipitation across northern Iowa associated with shortwave
will continue to push eastward through the morning hours...though
will begin to dissipate. Enough moisture in place to warrant probability of precipitation
across the north through much of the morning hours...though may have
kept too long into the afternoon hours. In addition...complex in
central NE will continue to push eastward...with models bringing
precipitation into central Iowa...and have therefore kept probability of precipitation
further south. As short wave pushes east...may see additional storm
development across western Iowa in the late afternoon hours as
instability increases and weak boundary approaches. Shear will be
somewhat limited...though given strong instability storms may be
strong to severe in the west in the late afternoon.

Long term /tonight through Thursday/...
issued at 329 am CDT Friday Jul 11 2014

Sat will be the active day of the forecast period with the cold
front moving through a very unstable airmass. Surface dew points
in the low to middle 70s will help push the convective available potential energy into the 3000 to
4000 j/kg range for Sat. Thunderstorms may well go through the
day. Timing will ge critical with temperatures. MOS temperatures seem a little
high for maxes on Sat...however a few hours of sun could easily
push temperatures into at least the middle 80s. Following the cold front a
sharp turn to colder conditions is expected with a sharp trough
rotating through the upper Midwest. Expect to see temperatures 10 to 20
degrees below normal for one to two days. Will mention near record
lows for Tuesday morning. There is a good chance that lows Wednesday will
be within 5 of a record as well. Highs both Tuesday and Wednesday will be
near the coolest maximum temperatures for the day across the state. Gradual
warming will begin for the later part of the week. The week looks
to be a dry week overall as well.


issued at 609 am CDT Friday Jul 11 2014

Winds will remain from the south...becoming southeasterly late in
period. Main concern will be thunderstorms and rain at sites through period. Several
chances...beginning early in period with thunderstorms and rain pushing east from
NE...and again overnight with late afternoon development
expected...which will likely continue to affect northern
sites...kmcw and Kalo...through the overnight. Have included thunderstorms in the vicinity
mention at this time due to uncertainty in timing and location. Thunderstorms and rain may
bring MVFR or lower ceilings and visibilities. Near 12z may see
MVFR or lower visibilities and ceilings behind system with
lingering moisture.


Dmx watches/warnings/advisories...



short term...awb
long term...MS

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