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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
627 am CDT Monday Sep 22 2014

issued at 622 am CDT Monday Sep 22 2014

Updated to include 12z aviation discussion.


Short term...(today and tonight)
issued at 417 am CDT Monday Sep 22 2014

Today-tonight...surface analysis shows the center of a large area of
surface high pressure over the middle Mississippi River valley with nearly
meridional flow aloft...helping enhance cold air advection this morning. Colder air
over residual moisture with clear skies and calm winds is helping
promote some patchy fog development...but any fog will burn off
shortly after daybreak. Surface high pressure atop the region
underneath incoming ridging aloft from The Rockies will spell lots
of sunshine with slightly warmer temperatures today due to increasing 500 mb
heights. Surface high pressure is expected to shift off to the east during the
day today while the ridge aloft moves ovhd through tonight. Return southerly
flow on the backside of the high means low temperatures Tuesday morning will not
be as cool as what is experienced this morning. However...there will
be a slight increases in clouds tonight...mainly over southwestern
response to a shortwave trough aloft over The Rockies. In eastern
portions of the County warning forecast area...where the center of high pressure will still
have some influence...winds will go calm again with the coolest
temperatures in the County warning forecast area so patchy fog looks to again develop over
western WI westward to the Minnesota state line. No precipitation is expected in the
short-term period.

Long term...(tuesday through sunday)
issued at 417 am CDT Monday Sep 22 2014

Sensible weather highlights for the extended period revolve around
upper level ridging bringing warm and dry conditions through the
end of the week. The only exception is late Tuesday into Wednesday
when a weakening upper level wave will move across the upper
Midwest and spread clouds over MN/WI. Aside from the high
confidence in clouds...a few light rain showers are possible as
well...especially across the western County Warning Area. The low level dry air
and lack of elevated instability will keep most locations
dry...but continued with small chances for showers. Temperatures
will continue to run 10 to 15 degrees above the seasonal average
for late September.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 622 am CDT Monday Sep 22 2014

Aside from shallow morning ground fog at stations mainly away from
kmsp...VFR conds to prevail through tmrw morning. Any mifg this morning
will burn off by 14z. There is a small chance of seeing some fog
again in western WI...affecting krnh and Keau...but chances are too low
for inclusion at this time. Backing winds today through tonight with speeds at or below 10

Kmsp...VFR throughout with no significant impacts to aviation

/Outlook for kmsp/
Tuesday...VFR. Winds S 10 kts.
Wednesday...VFR. Winds S 12-15 kts.
Thursday...VFR. Winds south-southeast 7-10 kts.


Mpx watches/warnings/advisories...


short term...jpc
long term...jrb

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