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Area forecast discussion 
National Weather Service Des Moines Iowa
338 PM CDT Thursday Jul 31 2014

issued at 322 PM CDT Thursday Jul 31 2014

A weak boundary will move through the state tonight...with another
upper level system brushing the state on Friday. Weak high
pressure will follow over the weekend. Low pressure will organize
over The Rockies and consolidate over South Dakota and Nebraska by late Monday
and Tuesday...then move slowly east across the area through middle week.


Short term /tonight/...
issued at 322 PM CDT Thursday Jul 31 2014

Upper level shortwave continues to drop southeast across Iowa with
weak convective elements...showers mainly...over eastern Nebraska
along the Missouri River. The showers and potential for isolated thunder
are continuing to hold together with the help of an h500 wave and
weak surface low and front. For the most part will continue chances of
showers and isolated thunder through the evening with activity
diminishing late as instability wanes. Bufr soundings for the
western areas shows decent middle level lapse rates through afternoon
and early evening...and MLCAPE about 500-700 j/kg. Little threat for
any hail or wind with storms this afternoon. Overnight lows will
remain in the 50s to lower 60s with clouds lingering across the
south during the overnight hours.

Long term /Friday through Thursday/...
issued at 322 PM CDT Thursday Jul 31 2014

As the upper disturbance moves southeast across the area on
Friday...there will be another period of isolated thunderstorms over
the northeast half of the state.

A quite weekend is ahead with weak high pressure moving across the
central U.S. Temperatures will be close to a few
degrees below for the next few days...warming to about normal as
moisture increases.

The next weather system is stronger than we have seen in the past
week. Some shift in the models over the past few days with the
trend shifting northward slowly with each run. The best dynamics
are across the north with Tuesday and Wednesday looking to be the most
active. Cape increases in excess of 4000 j/kg with decent
divergence and Theta-E advection over the north half of the state
the southwest will not likely see much in until closer to frontal passage.
High pressure will bring cooler and drier air by Thursday.


issued at 1236 PM CDT Thursday Jul 31 2014
weak area of convection across western Iowa will move east-southeast and may
clip kdsm prior to ooz...otherwise only isolated development across the
region this afternoon as weak wind shift drops southeast across
the area. Winds will remain light and scattered/broken ceilings should give way
to generally sky clear/scattered conditions overnight. After 15z Friday bufr
soundings again show scattered-broken VFR conditions across the area.


Dmx watches/warnings/advisories...


Synopsis...MS Jul 14
short term...rev
long term...MS Jul 14

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