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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
1256 am CDT Fri Oct 28 2016

Update...updated for 06z aviation discussion below.


Short term...(this evening through friday)
issued at 318 PM CDT Thu Oct 27 2016

Main concern in the near term is timing of any clearing across the
region tonight and how warm to go Friday afternoon.

Pesky narrow band of light showers/sprinkles exiting west central
Wisconsin late this afternoon. It should remain dry the remainder of
the period. Lower clouds remain over most of the County Warning Area this moist lower level southeast/south flow continues.
Still anticipate overall lower cloud clearing trend to occur during
the night. Latest rap showing lower level relative humidity clearing
to the northeast...along and north of i94 through about 07z. Slower
to clear into western Wisconsin. Southerly winds will remain up this will preclude significant fog from forming. Did
mention some patchy fog to the far east...where winds will be

Warming ahead of the incoming cold front should warm temperatures
into at least the lower 70s to the southwest...record for msp is 75
in 1948...with mid/upper 60s common elsewhere. The front will
contain a fair amount of high clouds...but we expect the lower
clouds to gradually break up over the far eastern areas into Friday
morning. They may return in the afternoon with the approach of the
cold front and lower level begin to saturate again. Will likely see
some wind gusts around 30 mph into the afternoon...mainly into south
central Minnesota as the gradient tightens vicinity of the front.

Long term...(friday night through thursday)
issued at 318 PM CDT Thu Oct 27 2016

A progressive weather pattern will set through next week with
several upper level waves brining areas of surface high pressure and
low pressure though the region. This will bring windy conditions
across the upper Midwest. The best chance for rain will be Saturday
afternoon across central Minnesota/WI, and again on Monday across northern
MN/WI. At this time no heavy precipitation is expected.

On Friday night a cold front will move through the region. H850
temperatures at forecast to go from 15c to around 0c between 00z
Saturday and 00z Sunday. This cold air advection will keep the
boundary layer mixed and Saturday will be cool and blustery with
northerly winds of 10 to 20 mph. An upper level shortwave will skirt
west to east across the region and lead to mid level clouds along
with some light rain, but accumulations should only be around a
tenth of an inch or less since this system will be weakening, not

Sunday will be the nicer day of the two this weekend as high
pressure builds across the region and then tracks eastward during
the day. Therefore expect light winds to start off the day, but then
a warm southerly breeze will ensue during the afternoon. Monday
winds will increase once again, and in fact will likely end up
higher than currently forecast, especially if there is some sun in
the warm sector across southern Minnesota. Most of the precipitation will
stay north of I-94 on Monday.

Looking ahead, a cold front will push well south of the area Monday
night, but there is not much temperature advection. The rain will be
focused along this frontal boundary while high pressure brings dry
weather for the upper Midwest.


Aviation...(for the 06z tafs through 06z Friday night)
issued at 1249 am CDT Fri Oct 28 2016

Main challenge with this period is how the low stratus edge will
move tonight as low level southwesterly winds continue ushering
drier and warmer air in well ahead of a cold front that will
eventually move through near the end of the period. Low stratus
will be stubborn to move overnight and the guidance is all over
the board on how to handle it. Thinking some of the models are a
little overzealous in blowing the low clouds out too quickly,
though. Gusty winds are likely during the day today, and with very
strong winds just off the surface, did include wind shear at krwf.

Kmsp...dry southwesterly flow is pushing in, but the main question
is when will the edge of the clouds break over msp. Fcm already
scattered out, as did lvn to the south. So, bumped up the
scattering time to the overnight period, but there is a chance the
cloud deck halts its progression as the night progresses.

/Outlook for kmsp/
Sat...VFR with MVFR/rain showers possible. Wind north-northwest at 5-10 kts.
Sun...VFR. Wind south-southeast 5 kts.
Mon...VFR. Wind S 15g25 kts.


Mpx watches/warnings/advisories...


Short term...dwe
long term...jrb

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