Area Forecast Discussion
Issued by NWS Des Moines, IA

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FXUS63 KDMX 300536

National Weather Service Des Moines IA
1136 PM CST Tue Nov 29 2016

.SHORT TERM.../Tonight through Wednesday/
Issued at 258 PM CST Tue Nov 29 2016

Upper low that has been impacting the region over the last few days
continues to spin across central MN tonight into Wednesday. It will
wobble around into Wednesday before finally beginning to push SE
into WI/Great Lakes region Wednesday night into Thursday. A few
waves of energy rotating around the parent low to drop through the
state bringing some chances for precipitation tonight into Wednesday
evening. The first is currently dropping through SE SD and WC MN and
will move through northern Iowa tonight. This is responsible for a
large area of light snow moving through ERN SD/WRN MN and just into
NW IA. The area of snow is expected to continue to progress ESE
through northern IA tonight. It is fighting some drier air in the
lower levels, so progression southward into the CWA is expected to
be limited. Otherwise decent chance for very light snow across the
northern few tiers through much of the night. Much deeper saturation
expected into Wednesday with a stronger lobe of energy dropping
through the day. This is expected to create more widespread light
precipitation that could extend as far south as I-80, before
precipitation begins to diminish from the east. By Wednesday
evening, the majority of the precipitation is expected to be
confined to the northeastern portions of the CWA closer to the main
upper low with energy wobbling around the main system as it meanders
into SRN WI. Therefore have some broadbrushed pops through the next
36 hours, and bumped up pops quite a bit to categorical/likely
across the north into Wednesday. Overall moisture is limited, which
will limit accumulations with mainly a dusting to just under an inch
expected mainly along and north of hwy 20. The greatest amounts of
around a half inch to close to an inch expected along the two
northern tiers of counties. Temperatures not expected to climb much
Wednesday either so expect temps mainly in the 30s through the day,
and close to 40 southeast.

.LONG TERM.../Wednesday night through Tuesday/
Issued at 258 PM CST Tue Nov 29 2016

Precipitation expected to taper off from west to east Wednesday
night with mainly dry conditions into Thursday. Some residual
energy moving through aloft Thursday could lead to greater
cloudiness, but overall enough dry air that any precipitation not
expected at this point. The drier and cooler period is expected to
remain into the weekend.

EC/GFS/Canadian coming together with the split upper level flow
regime into the weekend, keep cooler west to northwesterly flow
across the region and cutting off an upper low across the
southwestern US. One shortwave trough moves through later Saturday
into Sunday and could see some light precipitation with that system,
with another wave lifting through the region into Monday. This would
the system from the SW US filling as it lifts NE and is brought back
into the main upper level flow pattern as a large trough digs across
the western US. This could bring some more light precipitation into
Monday with more of a rain/snow mix across the CWA. Otherwise all
extended range models looking more active just beyond the period
into the middle/end of next week as they eject energy out of the
Rockies with the western US trough shifting eastward and a weather
system organizing across the central US. Will have to monitor this
system in the coming days as it moves into the forecast period, as
it could be the next widespread chance of precipitation for the


.AVIATION.../For the 06Z TAFS through 06Z Wednesday night/
Issued at 1136 PM CST Tue Nov 29 2016

Overall thinking has changed little since 00z. MN surface low
pressure will slowly drift toward the Great Lakes through the
period keeping IA in broad cyclonic flow. This will result in
widespread IFR to MVFR ceilings. After isolated sprinkles or
flurries early this morning, generally not worth a mention in
TAFs, rain and/or snow is expected to spread into the northern
half of the state into the afternoon reducing visibilities to IFR
or MVFR at times as well.





SHORT TERM...Beerends
LONG TERM...Beerends
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