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fxus63 kdmx 140452 

Area forecast discussion
National Weather Service Des Moines Iowa
1052 PM CST Wed Nov 13 2019

Discussion.../tonight through Wednesday/
issued at 347 PM CST Wed Nov 13 2019

A shortwave is currently pushing through northwest Iowa and will
quickly move east of the state this evening. Lack of deep
moisture...or patchy deeper moisture at best...with this system
until you get to eastern Iowa led to freezing drizzle/freezing rain
across west central Iowa through early afternoon. Currently the main
band of precip is along and north of the Highway 30 corridor with
the better forcing beneath the dendritic growth zone so the forecast
of light snow with an inch or less accumulation still looks good. I
did nose snowfall amounts up a couple tenths from Waterloo to south
of Marshalltown as they had some snow this morning/early afternoon
which put some minor accumulations down. Total snowfall for the day
may be a touch more than an inch with the earlier snowfall.

By 9 PM snow will be east of the area with cloud cover gradually
diminishing overnight. With the passage of the shortwave, a brief
shot of cooler air comes in for tonight and Thursday though there
will not be an Arctic intrusion so we will not see temps as cold as
they have been.

For Thursday through Friday, an upper ridge builds across The
Rockies and while the NAM and GFS suggest a weak wave passing across
northern Iowa this seems insignificant and with a large surface high
over the region and into the Great Lakes, i'm going with the dry and
warmer forecast that we have going.

Late Saturday and Saturday evening, a considerably stronger
shortwave will pass through the region. There appears to only be a
brief window where moisture is sufficiently deep and forcing is
decent for light rain or snow depending on timing.

Beyond this, upper ridging will slide east of The Rockies for early
to mid next week bringing near to possibly slightly above normal
temps. The longer term also looks dry as well.


Aviation.../for the 06z tafs through 06z Thursday night/
issued at 1052 PM CST Wed Nov 13 2019

Main concern yet through 07-08z will be small chance of -fzdz over
the east. Loss of ice and MVFR cigs of 010-015kft have been
producing some patchy fzdz over the area; though not expected to
last long. Second front over Minnesota spreading another area of stratus
which should mainly affect kmcw/Kalo and perhaps kotm/kfod. Winds
remain northwest under 12kts and cigs return to VFR between 13-17z
with mainly high sct clouds aft 19z. /Rev


Dmx watches/warnings/advisories...

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