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Area forecast discussion 
National Weather Service Des Moines Iowa
1234 PM CDT Monday Apr 27 2015

Short term /today/...
issued at 335 am CDT Monday Apr 27 2015

High pressure from western Hudson Bay into Nebraska will move
little today with little change in the weather from yesterday.
Will go with a persistence plus 4-6 from yesterday given some
slight warming at 800 mb. Light winds and clear skies will prevail
today...with only weather being some patchy frost early this
morning over the north half.

Long term /tonight through Sunday/...
issued at 335 am CDT Monday Apr 27 2015

Only a few minor changes with the ongoing forecast but with the
continued dry weather pattern through much of the work
week...a persistence forecast seemed sensible.

Tonight into Thursday...weak trough embedded in the north to
northwest flow aloft and some middle-level Theta-E advection looks to
bring some cloud cover to the state Tuesday afternoon into early
Wednesday morning. With very little forcing and moisture
available...left forecast dry at this time and with the slightly more
cloud cover Tuesday night went slightly warmer than guidance for
low temperatures. Tuesday through Thursday looks to be fairly
similar for maximum temperatures...with the best mixing day on Wednesday and
thinking it will be the warmest day of the three. Albeit only
slightly warmer. Guidance remains too low through Thursday and
confident to go a few degrees above guidance throughout the entire
week.

Friday through Sunday...finally by the end of the week the slow
moving surface low across the south-southeast gets a little boost
from an upper low quickly pushing south out of the Great Lakes and
pushes into the Atlantic by Friday. The forecast area remains in
zonal flow Friday and through the weekend with the extended models
depicting a few ripples of energy providing enough forcing for
scattered thunderstorm activity over the weekend. Timing these
shortwaves remains uncertain and mainly left slight to chance probability of precipitation
going over the weekend.

&&

Aviation...27/18z
issued at 1234 PM CDT Monday Apr 27 2015

Widespread VFR conditions will persist across all of Iowa for the
duration of the forecast. Visibilities will remain unrestricted
with any ceilings coming from high cirrus moving overhead. Winds
will be from the north to northeast during the day and light and
variable at night.

&&

Dmx watches/warnings/advisories...none.

&&

$$

Short term...MS Apr 15
long term...podrazik
aviation...cogil

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