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Area forecast discussion 
National Weather Service Des Moines Iowa
1150 PM CDT Friday Apr 24 2015

Short term /tonight/...
issued at 336 PM CDT Friday Apr 24 2015

Surface low in western Kansas will lift northeast throughout the
overnight...reaching northern Missouri by end of period. As system
lifts north will see another round of precipitation begin to spread
into southern Iowa overnight tonight. Before this...ongoing
precipitation will continue to push eastward. Have trended towards
high res model solutions...with precipitation diminishing as forcing
pushes out. May see continued development along eastern edge through
the late afternoon and early evening. As low approaches forcing will
begin to push into northern Missouri near 06z and central Iowa near
12z. Have kept probability of precipitation confined to the south through much of the
overnight...spreading north primarily after 06z. May still be too
aggressive on northern extent of precipitation and timing of onset in
southern Iowa. Moisture will increase ahead of system and precipitable water
values will be near/over 1 inch in the south near 12z. This is
climatological high...and with deep saturation noted through
column could see some heavy rain at times near 12z...and have
increased quantitative precipitation forecast across the south. Have kept temperatures generally
near going with clouds and precipitation keep temperatures fairly
steady through the overnight.

Long term /Saturday through Friday/...
issued at 336 PM CDT Friday Apr 24 2015

Primary sensible weather will be early in the period with little in
the way of precipitation and seasonal moderating temperatures into next
week. Southwestern U.S. Long wave trough and leading short wave currently
approaching the Texas Panhandle will fairly rapidly mature into the
evening with deep forcing into southeast Iowa and immediate MS valley Sat
morning. Although this deep lift will exit into Illinois by
midday...295/300k isent surfaces show trowal remnants and weak lift
in Ely flow lingering into central Iowa with patchy light rain and/or
drizzle. Although MUCAPES get into the hundreds south early...the
soundings show rather weak and disjointed vertical wind profiles
so severe storms are not anticipated. Raw temperatures vary quite a bit
Sat so these discrepancies and some non- diurnal trends will
result in reduced temperature confidence. Do not want to lower
things too much however...so expect low/middle 50s for highs with
brisk northeasterly winds making it feel even cooler.

Models depict drying from the northeast into the night so expect
clearing skies from that direction leading into an extended period
of relatively weak split flow and inactive weather from late in the
weekend on. Another southern stream wave will cross the Central Plains
and lower Ohio Valley...but with little effects this far north. Northern
stream wave will drop into the northern plains/upper MS valley around Tuesday
or Wednesday. There is some forcing but moisture is limited and never
really phases with adequate depth or saturation so extended forecast
remains dry. Temperatures will gradually moderate into next week...but that
is mainly due to more insolation as the calendar progress than any
significant airmass change.

&&

Aviation...25/06z
issued at 1150 PM CDT Friday Apr 24 2015

Ceilings will continue to lower overnight as a system approaches from
the south. Expect a widespread area of IFR by late tonight into
Saturday morning. The precipitation will be mainly over central
and southern Iowa in the morning then diminishing. Gusty east to
northeast winds through Saturday afternoon.

&&

Dmx watches/warnings/advisories...
none.
&&

$$

Short term...awb
long term...small
aviation...donavon

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