Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 190847

National Weather Service Des Moines IA
347 AM CDT Wed Oct 19 2016

.SHORT TERM.../Today/
Issued at 345 AM CDT Wed Oct 19 2016

Upper system will pass into the Plains today approaching the Lower
Missouri River valley by this evening.  Decent mid level
frontogenetical forcing develops across central/northern Iowa this
morning into early afternoon ahead of the system which will aid in
continuing cloudiness through the day and some hint of
precipitation.  However, dry north to northwest flow from around
750mb to the surface will undercut the moist layers aloft and will
hinder precipitation from reaching the ground in most instances.
That`s not to say some sprinkles will not reach the ground but will
overall limit the chances of seeing much in the way of measurable
precipitation across the forecast area during the day.  The thicker
cloudiness and weak cold advection will also limit heating and keep
readings cooler than on Monday.

.LONG TERM.../Tonight through Tuesday/
Issued at 345 AM CDT Wed Oct 19 2016

Summary...Primarily quiet, pleasant conditions into next week.
Temperatures will bottom out Thursday then rise above normal into
the 60s for the remainder of the forecast. Fleeting opportunity for
light precipitation tonight, then next opportunity not until mid
next week.

Wednesday night through Thursday...As upper trough continues to push
into the plains, best forcing and moisture combination will remain
south of the state. As the trough begins to pivot through Wed
evening, strongest wave/vort max will move through overnight but
will struggle produce any precipitation. Indications continue that
dry air will win out and prevent most, if not all, precipitation in
the area. That said, may remain possible to eek out highly scattered
light rain. With confidence low and spatial extent small, have kept
with removal of POPs overall. Thursday will be coolest day in the
package, with highs in the 50s as northwest winds prevail.

Thursday through Tuesday...Models generally in good agreement
regarding overall pattern. Upper level flow will be quiet into next
week with northwest flow and ridging primarily dominating before
southwest flow returns Tuesday. Surface flow will shift southerly by
Friday and mostly remain so through the remainder of the package,
helping boost temperatures into the 60s, possibly touching 70 at
times. Next opportunity for precipitation, even thunder, returns
Tuesday night concurrent with good surface moisture return and more
active southwest upper level flow.


.AVIATION.../For the 06Z TAFS through 06Z Wednesday night/
Issued at 1137 PM CDT Tue Oct 18 2016

VFR conditions are expected through the forecast period with light
and variable wind generally becoming North at 10kts or less. An
upper level trough will approach by late in the period finally
passing through the state by 18Z Thursday.  Most of the forcing with
this stays West then goes South of the state only brushing Western
Iowa.  There is such a deep layer of dry air from just off the
surface to around 10KFt that I do not see much threat of precip.
Maybe sprinkles if we can get enough forcing into Western/Southern
TAF locations but the main impact will be an increase in mid clouds.




LONG TERM...Curtis
AVIATION...FAB is the U.S. government's official web portal to all federal, state and local government web resources and services.