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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
115 PM CDT Friday Oct 9 2015

Updated for 18z aviation discussion...
issued at |108 PM CDT Friday Oct 9 2015


Short term...(today and tonight)
issued at 310 am CDT Friday Oct 9 2015

Relatively quiet short term period ahead. Initial forecast concern
this morning is dealing with the cloud cover and its impact on
temperatures across the area. Hrrr has performed well in handling
the clouds overnight...indicating last evening that a hole would
be blown open in the cloud deck from Western Lake Superior through
east central Minnesota and west central WI. Clouds continue to plague
western Minnesota early this morning which is expected to continue
through the morning hours. Hence...increased low temperatures for
this morning out west as additional cloud cover there continues to
hold strong. The expectation with the cloud cover is that the dry
wedge of clear skies will slowly transition east...and the clouds
over western Minnesota will do the expect an increase in cloud
cover across eastern Minnesota this morning. As the day
progresses...drying conditions and anticyclonic upper flow will
diminish the cloud deck...expect it to scatter out by late this
afternoon/early evening. With the cooler air mass and come cloud
cover during the day...highs will be held in the upper 50s for
most...except for some low 60s in far western Minnesota.

The surface ridge will work across the area this afternoon through
the northwesterly winds will eventually turn
southwesterly. The high will depart through the night and we'll
see southwest winds increase through the night as the pressure
gradient begins to tighten. No precipitation is expected during
the short term forecast period.

Long term...(saturday through thursday)
issued at 310 am CDT Friday Oct 9 2015

Rather few issues to deal with in this extended forecast pkg.

Surface high pressure will settle over the Great Lakes/Ohio River valley
regions while a large surface ridge over The Rockies shifts into the
central states. This will promote strong warming over the upper miss
River Valley due to strong southwesterly surface flow and increased 500 mb heights to
the 576-579 dam range. 850 mb temperatures will increases to around 20 degree c by
sun...and this will be in conjunction with the ridge axis moving
atop the region. Thus...Sunday has potential for record highs for
multiple sites within the weather forecast office mpx County warning forecast area. Mixing still does not look
as optimized as possible due to a slight relaxing of the wind
fields...thus temperatures may fall just short but still hit the lower 80s
for much of the County warning forecast area.

An approaching cold front for Sun night into Monday will bring a sharp
difference in temperatures going into Monday to the tune of 15-20
degrees cooler cwfa-wide. There is very little moisture associated
with this frontal have confined only slight chance probability of precipitation to the northern
and eastern fringes of the County warning forecast area for during the day on Monday. However...a
very tightened pressure gradient along with vorticity packing with the
frontal passage will mean a strong increase in wind speeds for Monday...
possibly to Wind Advisory criteria so will need to see how the models
develop this scheme over the next couple of days.

Beyond Monday...the forecast remains dry with cooler but still above-
normal temperatures for next week.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 108 PM CDT Friday Oct 9 2015

VFR conditions throughout. 4000ft ceilings will linger this
afternoon...but should dissipate close to sunset. On Saturday
southwest winds will increase...with late morning gusts near
20 to 20 kts.


VFR conditions throughout. 4000ft ceilings will linger this
afternoon...but should dissipate close to sunset. On Saturday
southwest winds will increase...with late morning gusts near
20 to 20 kts.

/Outlook for kmsp/
sun...VFR. Winds south-southwest at 10g15kt.
Monday...VFR and windy. Wind northwest at 20g35kt.
Tuesday...VFR. Wind west-southwest at 15g20kt.


Mpx watches/warnings/advisories...


Short term...speed
long term...jpc

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