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Area forecast discussion 
National Weather Service Des Moines Iowa
1240 PM CDT Thursday Apr 17 2014

issued at 306 am CDT Thursday Apr 17 2014

Low pressure over southern Wisconsin will move to south of sames Bay
by Friday morning as a high pressure ridge builds into Iowa tonight.
Warm front will develop over northern Iowa Friday and lift north. Next
weather system will settle into Iowa for Saturday night into Monday. A
stronger weather system is slated to affect the area for the
middle and end of next week.


Short term /today/...
issued at 306 am CDT Thursday Apr 17 2014

Surface low will continue to quickly push off to the
northeast into the Great Lakes region this morning and allow for the
cold air advection to diminish late this morning. Surface high pressure builds into
the state this afternoon...but the main concern today is with
lingering cloud cover behind the cold front and low pressure system.
The 04.17.03z hopwrf has the best handle of the low stratus sticking
around through at least through 21z across the southeast sections of
the forecast area. The latest European model (ecmwf) hinting on the lingering clouds
cover...but is further southeast with the clearing skies. The NAM
bufr soundings not handling lingering cloud cover today and the GFS
bufr soundings depicting clearing by around 15z. So leaned toward
the hopwrf solution for cloud cover. With respect to temperatures...went closer
to the sref for temperatures today as the GFS looks too cold and the
NAM was too warm in the south where the stratus looks to linger much
of the day.

Long term /tonight through Wednesday/...
issued at 306 am CDT Thursday Apr 17 2014

Warm air advection along developing warm front will produce a few showers over
northwestern Iowa Friday morning...but in spite of strong Theta-E
advection...moisture is very limited and will only go isolated.
The next weather system for the weekend is slowing down and have
backed off probability of precipitation more on Saturday that we had out...and won't see
precipitation reach the far southeast until Saturday night. Along with
the delay in start time will be a delay in end time. Precipitation will
likely linger through a good part of Monday. With some limited
instability...100 to 400 j/kg...will keep isolated thunder in the
cards through Sunday...then drop off to just showers after that.

After a brief break Tuesday the next system will begin to move in on
Wednesday. Models have been consistent on the overall trend of a
significant trough moving into the western U.S. And pushing
through the ridge...ultimately ending up a a negative tilt trough as
it moves through the central U.S. This system will have time to
draw moisture into it. Dewpoint readings will make it into the
50s. K index in 30 to 35 range and decent cape available...around
1500 j/kg...went for straight thunder with this system.

Tempwise...after tomorrow expect to see temperatures warm. Above normal
overall weather can be expected by sun and continue through next


issued at 1240 PM CDT Thursday Apr 17 2014

MVFR stratus that covered much of central Iowa this morning has
quickly begun mixing out from west to east...and this trend is
expected to continue through the early afternoon hours will all
sites clearing out before 20z. Northwesterly winds of 10 to 15 kts
will also decrease this afternoon as a ridge of high pressure
approaches from the west. The ridge passes through overnight with
southeasterly return flow setting in by daybreak and increasing
through the morning hours.


Dmx watches/warnings/advisories...


Synopsis...MS Apr 14
short term...podrazik
long term...MS Apr 14