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Area forecast discussion 
National Weather Service Des Moines Iowa
631 am CDT Wednesday Apr 23 2014

Short term /today/...
issued at 322 am CDT Wednesday Apr 23 2014

Main challenges today will be temperatures...wind and precipitation.
Though moisture is somewhat limited at the moment at h850...models
have continue to nail convection that is developing across
northeastern Kansas early today along surface warm front and leading edge of
stronger wind fields/moisture channel aloft. Some moisture has made
it back to eastern OK... and suspect that this is the source of
current convection. This will drive northeast with time today and
fill in over our area between 12-18z as thetae advection increases
through middle morning. Best forcing will move northeast with time
through northeast sections of forecast area by late afternoon...but
some lingering showers will remain SW into central sections prior to
main short wave expected to move across the region tonight/Thursday.
Temperature forecast today somewhat challenging...starting day mild
with temperatures in the 40s to lower 50s south...but sustained east
southeasterly flow through a good share of the day north of the warm
front south of US today will cap highs in the 60s south and 50s
north. Shower activity will further prevent any rapid warming due to
evap cooling during the day. Forecast MUCAPE values today nearly none
across the area and will trim isolated thunder back to showers due to dry
airmass in place at this time. Gradient winds will pick up today
especially across the west. By late morning...southeast winds look
to be nearing or just about 30 miles per hour over the far west/northwest
through most of the afternoon. Will issue wind advection for small portion
of the western forecast area today.

Long term /tonight through Tuesday/...
issued at 322 am CDT Wednesday Apr 23 2014

Still dealing with the two main systems tonight into Thursday and
then the next one Saturday night into early next week. Initially
this evening expect an exiting area of showers to the east...with
the next more robust round of precipitation expected by late evening into
the overnight hours. Strong Theta-E advection/warm air advection setting up across
the area...with moisture transport very impressive and directed
right into central Iowa by 06-09z Thursday. Expect shower/thunderstorm
development across northern half of the County Warning Area this evening on the nose
of the Theta-E ridge...with more widespread activity by late evening
into the overnight hours...as the line of convection expected to
fire to the west later today pushes eastward through the County Warning Area as the
surface low slides into central Iowa by around sunrise Thursday. As the
entire system shoves east Thursday...expect precipitation to taper off from
west to east through the late morning/early afternoon hours. Dry
conditions then still expected for Thursday night into Friday. Weak
warm air advection with 850 mb temperatures around +10c to +12c across the area should allow
for a pretty decent Spring day across the area.

Attention then shifts toward the late weekend system...with a very
potent system digging into the intermountain west by Saturday. Upper
level system to close off and become nearly stacked toward
Sunday...with the main circulation moving very slowly from southeast Colorado at
12z Sunday to south central NE by 12z Monday. This places the state
in an active southwesterly flow pattern aloft...with impulses aloft
ejecting out ahead of the main upper low. This should bring rounds
of precipitation chances to much of the state beginning Saturday
night...and continuing into early next week. Hard to nail down the
timing of these impulses...therefore have some broadbrush high
chance/likely probability of precipitation across the entire County Warning Area from Saturday night through
Monday night. Models then shove the system east into the Ohio Valley
region with broad upper level troughing across the central/eastern
US and let the circulation spin there for a few more days. Therefore
expect an overall cooler period into Tuesday and the middle of next
week...with possibility of additional chances of precipitation
wrapping back into the County Warning Area. Overall models in better agreement with
the general trend with this system...and therefore certainty is high
that should see some sort of long duration precipitation event for
the state especially Sunday into Monday. It is the finer details
that still remain quite uncertain...including how much cold air will
wrap into the backside of this system. Ec is much colder...than the
Canadian/GFS at this time. Have left all precipitation mention in liquid
form...but if the ec verifies could have some snow mixing with the
rain or a brief changeover to all snow by Monday night across
portions of the County Warning Area.

&&

Aviation...23/12z
issued at 628 am CDT Wednesday Apr 23 2014

Area of showers heading across the network today and should be
east of i35 by 18z...east of Kalo/kotm by 23-00z. Other concern
early will be strong winds from southeast today...with sustained
winds 20 to 25kts most areas with gusts to near 30kts at times.
During 00-06z main system to arrive with another round of heavier
showers/storms lasting to end of period...resulting in lowering
ceilings to MVFR and visibility at 5sm during heavier rainfall./Rev

&&

Dmx watches/warnings/advisories...
Wind Advisory from 10 am this morning to 6 PM CDT this evening
for Calhoun-Carroll-Crawford-Emmet-Palo Alto-Pocahontas-SAC.

&&

$$

Short term...rev
long term...beerends
aviation...rev