Area forecast discussion National Weather Service Des Moines Iowa 310 PM CDT Thursday may 23 2013 Short term.../tonight /... issued at 310 PM CDT Thursday may 23 2013 Little of concern tonight with Iowa between High Plains ridge and departing Great Lakes trough. Although skies will be clear with light winds as surface high pressure crosses the upper MS valley...overnight lows should only dip into the upper 30s northeast keeping frost concerns at Bay. Long term.../Friday through Thursday/... issued at 310 PM CDT Thursday may 23 2013 Active period setting up for the Holiday weekend into next week...with main issued surrounding chances for thunderstorms and potential for heavy rain. High pressure initially over the area Friday with dry conditions expected...however the surface high quickly shoves east with warm air advection and moisture advection back into western Iowa by late Friday afternoon. This will allow for some potential thunderstorms across western Iowa late in the afternoon. Chances for thunderstorms to become more widespread across the County Warning Area as weak shortwaves push eastward through the upper level ridge expected to remain in place through the weekend. Thunderstorm chances will remain with the climatological favored times in this type of pattern...mainly in the evening to overnight hours and lingering into the morning. With the extended chances for thunderstorms and rainfall...flash flooding and river flooding becomes a concern. Moisture transport oriented into Iowa for much of the Holiday weekend...precipitable waters well above average increasing into the 1.3 to 1.5 inch range...and fz level quite high suggesting efficient rain production through the weekend. Widespread rainfall amounts of 1 to 2 inches with locally higher amounts are possible through the Holiday weekend. Severe parameters not that great...so widespread severe weather is not anticipated. Upper level ridge begins to shift east slightly and dampen some...with a surface warm front expected to lift northward through the state Tuesday. An upper level closed low digs into the Desert Southwest with impulses ejecting out ahead of the main system through the region. With the warm front stalling out across the County Warning Area Tuesday into Wednesday...and the energy lifting through the area...thunderstorm chances continue into next week across the area. Warmer temperatures also expected with the warm front lifting north...with much of the area returning to 70s and 80s by the middle of next week. && Aviation...23/18z issued at 1220 PM CDT Thursday may 23 2013 MVFR stratus roughly along rdk-csq-i75-pea-iow line at 1730z will continue to drift south at around 20 kts...exiting kotm by 19z. This will lead to clearing skies into the evening which will persist until scattered middle/high clouds increase late Friday morning. Expect minor gusts today to diminish toward sunset with light winds gradually veering to southeasterly by early Friday. && Dmx watches/warnings/advisories...none. && $$ Short term...small long term...beerends aviation...small