Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 222335

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
635 PM CDT MON AUG 22 2016

.UPDATE...For 00z Aviation discussion below


.SHORT TERM...(This evening through Tuesday)
Issued at 300 PM CDT Mon Aug 22 2016

Dry weather expected for the next 24 hours, but an area of showers
and thunderstorms will move up from the southwest Tuesday afternoon
ahead of an upper level wave. Early morning water vapor imagery
together with GFS 500 mb heights and winds identified the trough
across the OK/TX panhandle. This wave will lift northeast, and
forecast models are in good agreement with showers and thunderstorms
develop across the NE/IA border shortly after 18Z, and these storms
will move into southern MN Tuesday afternoon.

The highest threat for severe weather will be near initiation across
NE/IA, but there is a marginal risk for storms across Minnesota and
Wisconsin. Forecast soundings show around 1500 to 2000 J/kg of CAPE,
but the wind profile is very unorganized with a veered/backed
pattern, so there should a very limited ceiling on the extent of
severe weather.

.LONG TERM...(Tuesday night through Monday)
Issued at 300 PM CDT Mon Aug 22 2016

The extended period will remain progressive for the next 7 to 10

The best chance of widespread precipitation occurs from Tuesday`s
night, through Wednesday morning. Due to the progressive nature
and a strong west-southwest flow aloft, I would not be surprised
to see the precipitation end by sunrise Wednesday for most of MPX
forecast area. The only area of concern or lingering showers will
occur in west central Wisconsin where wrap around moisture and
instability showers/storms may occur as the system intensities
across the Great Lakes region.

As discuss earlier with the progressive nature of the extended
period, the next chance of precipitation may occur quicker Friday
then what models indicate. Based on current trends, most of Friday
should be dry with the exception in western Minnesota by the
afternoon. Usually as the low level jet kicks in, the best chance
of precipitation will occur Friday night. Depending upon the how
outflow boundaries interact with the instability over the weekend,
chances of showers and thunderstorms will continue. Timing and
placement remains questionable. It will also turn warmer and more
humid by Saturday/Sunday. The driest day in the next 7 will occur
on Thursday with temperatures will be 5 to 10 degrees below

The mean upper level flow continues from the west-southwest next
week along with embedded short waves diving southeast across the
Rockies and into the Northern Plains. One weather element that
remains favorable is near or slightly below normal temperatures
along with wetter than normal conditions. There are also no signs
of a big heat wave for the next 10-14 days.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 636 PM CDT Mon Aug 22 2016

VFR conditions will prevail through the TAF period. The main
concern is wind. Gusts will gradually subside this evening, but
will be replaced by low level wind shear concerns. Expect to see
2000ft winds around 45-50kts developing by 06z...from a 210-230
directional component. Surface gusts return around 15z Tuesday,
albeit a few knots lower than today`s speeds. A fairly sunny day
is expected on Tuesday, but mid/high clouds will be on the
increase toward the evening as convection develops over IA/SD.

Wind gusts will linger a bit longer into the evening than they
typically do, and then low level wind shear will develop from 06z
through a couple hours after daybreak when surface gusts re-
develop. Speeds on Tuesday will be a tad lower, generally
sustained up to 15 kts with gusts into the lower 20s (knots). Mid
level clouds will be on the increase toward the end of the period
as convection lifts toward the area from IA.

Wed...VFR with -TSRA/MVFR possible. Wind SW 5-10 kts becoming W.
Thu...VFR. Wind NW 7-10 kts.
Fri...VFR. Wind SSW 5-10 kts.


.MPX Watches/Warnings/Advisories...


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