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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
1214 PM CDT Friday Oct 21 2016

issued at 1203 PM CDT Fri Oct 21 2016

Updated to include 18z aviation discussion below.


Short term...(today and tonight)
issued at 353 am CDT Fri Oct 21 2016

Very little change in the forecast today and tonight as a storm
system brushes the Canadian border later today, and into tonight.

Early morning water vapor imagery has shown a sharp short wave
moving across the northern rockies and into the High Plains of
Montana. A weak surface ridge overhead will move eastward this
morning with a wind shift to the south-southwest. As the short wave
approaches, the pressure gradient will also strengthen, allowing for
southerly winds to increase, especially in western Minnesota. A
stronger downslope wind along the Lee of the Buffalo Ridge may allow
for higher temperatures than expected. The current forecast has low
60s east of this ridge, but I would not be surprised to see a few
mid/upper 60s if the right downslope component develops. Elsewhere,
highs will be in the 50s, with upper 40s/lower 50s in western

This system that will move along the Canadian border later
today/tonight is moisture starved and any lift/moisture advection is
limited. Therefore, precipitation is not expected, but skies
will remain partly to mostly cloudy.

Long term...(saturday through thursday)
issued at 353 am CDT Fri Oct 21 2016

A mild and dry weekend is still in the works, as high pressure
ridging dominates the north central Continental U.S. Between troughs on both
coasts. Conditions deteriorate early in the upcoming week as
energy from the West Coast trough spills into the plains.

On Saturday, temperatures will moderate to values nearing 10
degrees above normal, which translates to highs in the upper 50s
to mid 60s. On Saturday night, a shortwave will top the ridge and
ride along the international border, with the attendant surface
low passing across northern Minnesota. Moisture and dynamics will stay
well to the north of the forecast area, so do not expect any
precip locally or really hardly even any cloud cover.

By late in the weekend, energy from the western trough starts to
push into the Central Plains. Monday night looks to be the first
real opportunity for measurable precipitation, as isentropic lift
ensues north of the warm front lifting toward the area. Higher
chances for showers and thunderstorms arrive Tuesday night and
Wednesday as another surface low tracks from Iowa toward Lake Michigan.
One half to 3 inch rainfall amounts look to be common across the
forecast area, with amounts upward of 4 inches appearing possible
in southeastern Minnesota. With the slight southward shift in the low
placement over the last 24 hours, the threat for thunder looks to
exist south of the Twin Cities along the Interstate 90 corridor.
High temps will be cooler given the ongoing precip and increased
clouds, with upper 40s to mid 50s anticipated.

By Thursday the precip looks to clear out, although clouds will
likely linger. It will still be a mild day however, with highs
primarily in the mid to upper 50s.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1203 PM CDT Fri Oct 21 2016

VFR throughout this forecast package. Mid-level benign few-scattered
cumulus clouds under high-level broken-overcast cirrostratus clouds will
prevail through much of the day today into tonight as a warm
front shifts east from the Dakotas through Minnesota. The following cold
front will push through the region during the day tomorrow. No
precipitation is expected but winds will have multiple shifts
throughout the next 24-30 hours. The main factor is that speeds
will remain 8kt or less throughout with winds going light/variable
at times. In addition, the mid-level clouds are expected to
dissipate by tomorrow, leaving scattered high clouds in place. additional weather impacts are expected.

/Outlook for kmsp/
sun...VFR. MVFR cigs possible. Wind northwest 10-15 kt.
Mon...VFR. Wind light/variable.
Tue...mainly VFR. Chance MVFR/-ra late. Wind southeast 5-10 kt.


Mpx watches/warnings/advisories...


short term...jlt

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