Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 150901

National Weather Service Des Moines IA
401 AM CDT Sat Oct 15 2016

.SHORT TERM.../Today/
Issued at 359 AM CDT Sat Oct 15 2016

The main forecast concern was focused on cloud cover and
drizzle throughout the day today...and thus the impacts on
temperatures.  WAA looks to persist ahead of the surface trough over
the central to southern Plains.  The parent surface low looks to be
centered over the front range of the Rockies in eastern Colorado
with a secondary low centered over South Dakota. A nice fetch of low
level moisture will continue to stream into the state throughout the
day. Decent isentropic lift and enough QG forcing to cause for
drizzle through the morning into the afternoon hours. Typical
drizzle soundings per NAM/GFS Bufr with saturation below 850mb. The
hires models suggest the low ceilings and drizzle to persist through
much of the day with some lifting across the southeast. Have drizzle
mentioned through 20z then mainly light rain during the afternoon
hours. Expecting drizzle to begin in the southwest prior to 12z and
then across the rest of central Iowa b/t 11-15z. No major change
with ongoing temperature forecast with only a slight downward trend
across the south with the cloud cover expected to persist much of
the day.  Problematic temperature forecast with the strong WAA
throughout the day but the thick cloud cover and drizzle potential
counteracting any significant warm up. Leaned closer to the warmer
side of the models as the CWA remains in the lower 60s as of 09z and
confident temperatures could rise 9-12 degrees today.

.LONG TERM.../Tonight through Friday/
Issued at 359 AM CDT Sat Oct 15 2016

Slowing surface front will move into northern Iowa tonight before
stalling. Low level moist flow will be nearly parallel with the
front with convergence weakening with time. However, some showers
and storms will be possible in axis of low level flow across the
southeast half of Iowa overnight where weak instability will
reside. Meanwhile, farther north and west, winds will be light
near the front with near surface moisture in place along with weak
warm advection. Fog is expected to develop overnight in these
conditions, although the extent will depend if much status
remains limiting the near surface radiational cooling. Strong warm
advection become reestablished on Sunday and continues into
Monday. Very warm thermal ridge across the plains will slide east
into Iowa by Monday with very warm highs by afternoon. Near record
temperatures are expected during the day with decent southwest
surface winds and some sunshine helping temperatures climb.
The bulk of forcing during this time will be north of Iowa
limiting precipitation chances.

A cold front will sweep through the state Monday night with
decent cold advection into Tuesday. Cooler air will continue to
filter into the state through midweek as heights fall and upper
jet axis shifts southward. Medium range models begin to diverge in
the amplification of system toward the end of the period with Euro
more progressive and upper low closing off in the eastern United
States. GFS amplifies across the lower Missouri river valley and
is much more wet across the southern half of the state. Rain
threat will be mentioned in the forecast during this time given
the GFS solution but still plenty of uncertainty during this time
with the wide ranging solutions of the models.


.AVIATION.../For the 06Z TAFS through 06Z Saturday night/
Issued at 1139 PM CDT Fri Oct 14 2016

Current MVFR CIGS will gradually lower tonight to IFR/LIFR with
the lowest values over the south. DZ will develop overnight and
result in vsby restrictions across central Iowa through midday
Saturday. CIGs will lift to MVFR by afternoon with south winds of
10 to 15 kts with gusts to 25 kts. Low clouds will once again
develop tomorrow night.





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