Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 291509
AFDDMX

Area Forecast Discussion
National Weather Service Des Moines IA
1009 AM CDT SUN MAY 29 2016

.SHORT TERM.../Today/
Issued at 400 AM CDT Sun May 29 2016

The pesky upper level low pressure looks to finally push east of
the forecast area today and allow for surface high pressure to
build into the state. Weak westerly flow and dry air looks to
provide one of the nicer days the state has experience in some
time. Hence, the main forecast concern was focused on temperatures
and how warm they will reach. Leaned slightly warmer than
guidance for max temperatures temperatures today with enough
sunshine and mixing. There is a weak shortwave cutting across
Nebraska, but any convection associated with this system has
diminished. There maybe a stray shower that skirts across the
southwest this afternoon as this shortwave moves through, but low
confidence with anything significant due lack of moisture and
forcing available.

.LONG TERM.../Tonight through Saturday/
Issued at 400 AM CDT Sun May 29 2016

Warm advection and moisture transport will increase overnight
ahead of the next approaching shortwave. This will keep lingering
instability across the state overnight and combined with weak
forcing from the warm advection, may produce a few isolated storms
late tonight. Models diverge somewhat on Monday with GFS
remaining wet statewide as the NAM and EURO remain much drier. GFS
has been overly zealous on its QPF recently and easily convects
with this continuing with this system into early next week. Have
gone with the less ominous EURO/NAM solution and kept convection
isolated to scattered into Monday. Better forcing arrives late
Monday night into Tuesday with the approach of the upper trof.
Convection is expected to develop across the plains on Monday
afternoon near the surface boundary and advect eastward into the
state late Monday night. This convection will persist into Tuesday
ahead of the surface boundary with some threat of severe storms,
albeit somewhat limited given relatively weak shear and modest
instability.

The threat of precipitation will push east on Tuesday night into
Wednesday as the system progresses to the east. Increasing
subsidence on backside of system along with cooler Canadian air
will end precipitation chances by Wednesday night with dry
conditions through the end of the work week. The next threat of
precipitation arrives toward next weekend...although coverage and
intensity appear limited given the relative lack of return flow
into the state.

&&

.AVIATION.../For the 18Z TAFS through 18Z Monday afternoon/
Issued at 1009 AM CDT Sun May 29 2016

Have added chance of showers over the northeast this afternoon as
weak impulse will bring increase instability to region. May also
see iso thunder...though confidence on coverage small enough to go
with VCSH for now. Remainder of period will be quiet through 04z.
Will evaluate overnight for potential return thunder over south
two thirds...in 18z package. /rev


&&

.DMX Watches/Warnings/Advisories...
None.
&&

$$

SHORT TERM...Podrazik
LONG TERM...Cogil
AVIATION...REV



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