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Area forecast discussion 
National Weather Service Des Moines Iowa
1151 PM CDT Thursday Apr 24 2014

Short term /tonight/...
issued at 343 PM CDT Thursday Apr 24 2014

Main forecast concern was focused on lingering rain chances
over central to southeast Iowa late this afternoon into the early
evening hours. Area of low pressure and cold front already through
much of the forecast area and fetch of showers in south-central to
southeast Iowa will continue to push east-northeast ahead of the
low. The 04.24.12z hopwrf has a good handle on current radar trends
and has much of the precipitation east of the forecast area by 23z. Weak
middle-level Theta-E advection providing some light rain in the cold air advection
regime northwest of Des Moines but is fairly progressive and looks
to absorb by precipitation in the southeast.

Cloud cover will dissipate during the evening from west to east as
drier air wraps into the state. Winds also look diminish and shift
wester late tonight into Friday morning. Leaned toward the sref for
winds and temperatures tonight.

Long term /Friday through Thursday/...
issued at 343 PM CDT Thursday Apr 24 2014

Relatively quiet weather from Friday into Saturday with front
settling through the state Friday night into early Saturday. This
boundary will stall near the Iowa/MO border on Saturday with
increasing warm advection by afternoon. Temperatures on both days
should be at or above normal in most locations.

Western trough will continue migrating toward the state through the
weekend with active weather beginning Saturday night and
essentially remaining for the rest of the forecast. Strong warm
advection and increasing Theta-E advection is slated on Saturday
evening with strong 50-60kt low level jet directed into western
Iowa overnight. Convection is expected to develop during the
evening hours in the west and increase in coverage overnight as
strong forcing persists. Storms will be elevated and there will be
some threat of isolated severe storms producing large hail. Sunday
is shaping up to be an active day as strong moisture advection
continues into the state. Convection should be ongoing with some
decrease through midday. Instability axis will shift into
southwest Iowa by afternoon as warm front lifts into western Iowa.
There will exist some threat of surface based convection in the
southwest by late afternoon. Farther north...any convection will
be more elevated as cool air will remain near the surface. Shear
will be more than sufficient for organized storms and will have to
watch for a few tornadoes in the far southwest where warm sector
will exist. Convection will persist into Sunday night and push
eastward as drier air tries to rotate into western Iowa ahead of
now slow moving upper low. Surface low and boundary will remain
across Iowa on Monday and will be focus for additional
thunderstorms chances through the day.

System then meanders across the central United States for a good
portion of the week with low clouds...temperatures well below
normal and ongoing chances of light rain.


issued at 1144 PM CDT Thursday Apr 24 2014

Weak high pressure ridge will move over the state from the west
tonight and Friday. Some patchy MVFR and isolated IFR fog is
likely to develop around sunrise...mainly over the eastern taf
sites. VFR with light west winds on Friday. A weak boundary will
sink south in to the state Friday night. This will not cause any
weather...but will shift winds to the northeast.

Outlook...VFR will hold into Saturday. Warm front will lift into
the state sun into Monday with widespread thunderstorm activity


Dmx watches/warnings/advisories...


Short term...podrazik
long term...cogil
aviation...MS Apr 14