Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 230842

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
342 AM CDT SUN OCT 23 2016

.SHORT TERM...(Today and tonight)
Issued at 320 AM CDT Sun Oct 23 2016

Early morning water vapor imagery to the north nicely illustrates a
shortwave skirting the International border. This feature will
spread some clouds as far south as central MN/WI today, and spawn a
few showers across the north as well. At this point the forcing and
moisture sufficient for precipitation look to stay mostly north of
the forecast area, although a few early afternoon showers could make
it as far south as Ladysmith, WI. Breezy northwest winds will
develop this morning and afternoon as the associated surface trough
passes. The attendant cool air advection will cause temperatures to
be 5-10 degrees cooler than yesterday, with highs in the lower 50s
to lower 60s anticipated.

Tonight, clouds scatter out and winds become light and variable.
This will make for a chilly night, with Monday morning lows in the
30-35 degree range anticipated.

.LONG TERM...(Monday through Saturday)
Issued at 340 AM CDT Sun Oct 23 2016

Two concerns over the next several days as a strong storm system
begins to organize in the Central Plains and Upper Midwest

First, precipitation onset remains questionable on Tuesday due to
initial dry air mass to the east and how fast moisture builds
northward across the plains. Due to this drier air mass to the
east, the onset of precipitation could hold off across eastern
Minnesota until late in the afternoon, early evening. West central
Wisconsin may not see any precipitation until late Tuesday
evening, or early Wednesday morning depending upon the strength of
isentropic lift and how it will be oriented from southwest to

Secondly, this system is very dynamic and has very high anomalous
water content just to the south of MPX forecast area. Precipitation
water values of 1.0" to 1.2" along the Minnesota/Iowa border are
very rare for late October. Therefore, once this system become
very organized I would expect periods of heavy rainfall once the
setup develops along the nose of the low level jet Tuesday
evening. As with any system, any deviation of this jet and
orientation of the frontal boundary, will shift the heavier
rainfall amounts to the south or north.

Confidence remain very high on a wet period once the
precipitation starts, and will likely not end until the main short
wave moves through Wednesday afternoon/evening.

Further information on how much precipitation could fall is
evident in the latest GEFS QPF ensemble members which have
anywhere from 0.40" to 1.8" for the Twin Cities area by Wednesday
afternoon, with the mean and current operational run (00z/23) of
0.80". Further to the south across Iowa, these ensemble members
increase to 1.0 to nearly 2.4" with a mean and operational run of

Past Thursday, the progressive pattern will continue with a long
wave trough across the west coast, and weak ridging across the
plains. This will lead to several fast moving short waves and
associated frontal boundaries across the Upper Midwest by the end
of next week, and into the weekend.

This mean upper flow regime will hold the near or above normal
temperatures profile through the first part of November over the
Upper Midwest. The orientation of the PNA and AO would also suggest
that the warm pattern will continue through the first week of
November. I don`t see any major cold waves until the PNA becomes
more positive or the AO becomes positive.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1023 PM CDT Sat Oct 22 2016

Few changes made to the TAFs with going forecast looking on track
in terms of timing the wind shift with the low and front coming
through late tonight/early Sunday morning. In addition, confidence
has increased further on MVFR cigs remaining north of the MPX
terminals, save for a small chance for some MVFR cigs at AXN
around 15z.

KMSP...the hrrr has been very stable with its timing of the wind
shift Sunday morning and confidence is high in a 14z fropa.
Confidence is high in the rest of the forecast as well.

Mon...VFR. Winds bcmg SE at 5KT.
Tue...BCMG MVFR with -RA. Chc IFR late. Wind ESE at 10G20kt.
Wed...MVFR/IFR/-ra early. Then MVFR. Wind ENE at 5-10kt.


.MPX Watches/Warnings/Advisories...


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