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Area forecast discussion 
National Weather Service Des Moines Iowa
628 am CDT Wednesday Jul 30 2014

Short term /today/...
issued at 327 am CDT Wednesday Jul 30 2014

Temperatures and how to deal with precipitation potential remain the primary
concerns today. Iowa remains between influences of broad cyclonic flow
of Hudson Bay upper low...and forcing associated with right entrance
region of northwest-southeast Iowa jet segment with short waves drifting over western
Continental U.S. Ridge through The Rockies. Airmass is more thermodynamically
favorable for precipitation SW and NE of Iowa...especially any
potential locally is minimal. Our scenario will be very similar to
yesterday...driven by shallow weak instability with little low level
focus or convergence. Areal coverage of anything that forms would be
very minimal...well under 10 percent. Thus will keep silent mention
and forecast dry outside of far NE corner closer to better MLCAPES.
Expect scattered showers toward the Great Lakes...similar to
yesterday...possibly just clipping Mason City and/or Waterloo areas
but chances are still not great and relegated to slights. 0-2km
temperatures continue to nudge up just slightly day to day so have added a
degree or two to persistence for highs.

Long term /tonight through Monday/...
issued at 327 am CDT Wednesday Jul 30 2014

Little change in overall thinking for the long term forecast
tonight...with the rest of this week dominated by a deep trough
across the eastern half of the U.S. Resulting in mild and quiet
weather across Iowa. Have held probability of precipitation out of most periods despite
the potential for a few small showers at the coverage
would be very low and the impacts essentially none. The most likely
periods for rain will be around late Thursday and Friday...but
even then probability of precipitation are held at 10 to 20 percent due to the expected
low coverage. Meanwhile have continued trend of warming maximum temperatures
by a degree or so each day as the airmass slowly modifies but all
in all the sensible weather will be pretty steady state for the
remainder of this week.

By the middle of the weekend the eastern U.S. Trough will finally
be moving away and the western U.S. Ridge will be reassembling
itself over The Rockies...with Iowa lying near the northeastern
periphery of the ridge and close to the proverbial ring of fire.
During the first half of next week this will likely result in a
somewhat more active weather pattern...depending on how strong the
ridge is and where the associated zone of rainfall sets up...with
temperatures a bit warmer and a return of more significant
rainfall chances around or just beyond the end of the current
seven day forecast period.


issued at 628 am CDT Wednesday Jul 30 2014

Conditions very similar to the past few days are again anticipated
through the period. Expect VFR conditions throughout with scattered-broken
VFR ceilings during peak heating of the day and clear skies with light
winds overnight.


Dmx watches/warnings/advisories...none.



Short term...small
long term...Lee

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