Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 240855

Area Forecast Discussion
National Weather Service Des Moines IA
355 AM CDT Mon Jul 24 2017

.SHORT TERM.../Today through Tonight/
Issued at 355 AM CDT Mon Jul 24 2017

Surface high pressure will dominate the weather pattern today
providing plenty of sunshine and much needed cooler and less humid
air today. Dew points are likely to range in the lower 60s
through the period with temperatures remaining near or slightly
below normal through tonight. Some low stratus seems possible
across the northeast today with soundings suggesting saturated
around 3kft. This will keep temperatures down slightly and went
closer to the NAM for highs.

.LONG TERM.../Tuesday through Sunday/
Issued at 355 AM CDT Mon Jul 24 2017

Warm advection will be ongoing at the beginning of the period with
fairly strong theta-e advection as well. There may be some threat
of convection in northern Iowa although best lift and convergence
remain a bit farther north into Minnesota where pops will be
higher. Otherwise, readings will be quite a bit warmer with more
humid conditions as the moisture returns. The bulk of convection
on Tuesday night will remain north of the state near the surface
front where convergence will be maximized overnight. Temperatures
will remain quite warm overnight with the warm sector across the
state along with steady south winds.

The boundary will drop into the state on Wednesday with a weak
surface low into southeast Nebraska. This will help to enhance
inflow into the boundary by afternoon and likely back winds a bit
more as well. This backing should locally increase low level shear
and given the decent instability, strong to severe storms are
expected by afternoon into the evening across much of the forecast
area. Main severe threat will be damaging winds and some large
hail although the localized backing may aid in the development of
a tornado or two. This convection will dive southeast overnight as
the surface low progresses to the east and south with cooler and
drier air spreading into the state on Thursday. Thereafter,
persistent ridging in the western United States will keep the
upper Midwest in northwest flow aloft. It appears overall
temperatures will be at or below normal into the later half of the
upcoming work week into next weekend as this pattern maintains.


.AVIATION.../For the 06Z TAFS through 06Z Monday night/
Issued at 1138 PM CDT Sun Jul 23 2017

Main concern this TAF cycle continues to be the fog development
expected later tonight as well as some low clouds that may slip
into northern Iowa. Low MVFR with TEMPO IFR/LIFR visibilities are
expected over the north central Iowa terminals, especially KMCW
and KFOD. Farther east, while there will be patchy fog,
restrictions are a bit more uncertain so maintained TEMPO MVFR
visibilities. Other concern are low clouds over southeast
Minnesota that will drift southwestward. This may bring some
scattered to broken ceilings around MVFR restrictions at KMCW
later tonight into Monday morning. After the fog dissipates in the
morning and any low clouds scatter, VFR conditions will prevail
as high pressure drifts over the western Great Lakes.





SHORT TERM...Podrazik
AVIATION...Ansorge is the U.S. government's official web portal to all federal, state and local government web resources and services.