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fxus63 kmpx 210405 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1105 PM CDT Fri Jul 20 2018

Short term...(this evening through saturday)
issued at 252 PM CDT Fri Jul 20 2018

Isolated showers are redeveloping this afternoon. Clearing skies
and temperatures rising into the upper 70s/low 80s are building
instability. Could see some of these showers develop into
thunderstorms through early evening before losing instability
around sunset. So far, lightning activity has been confined to
northern Minnesota. Coverage is not expected to be particularly
widespread, perhaps 30-40 percent.

Widespread smoke across northwestern Minnesota associated with
wildfires over southern Canada will drift south tonight. Visibilities
range from 2 to 5 miles. The rap smoke model maintains this plume
overnight into southwest Minnesota, which seems reasonable with an
inversion trapping the smoke near the surface and continued northerly
flow. The mpca has posted an air quality alert for northwest and
portions of west central/central Minnesota through mid morning
Saturday before better mixing takes over.

Long term...(saturday night through friday)
issued at 252 PM CDT Fri Jul 20 2018

Overall, models continue to support a cooling trend after the
middle of next week as the mean wind in the boundary layer
contributes to a more Canadian air mass regime.

For The Ladder part of the weekend, and into early next week, the
anomalous upper low, which is currently located across the
western Great Lakes, will drift southward and weaken over the next
few days. This will keep deep tropical moisture limited to the
far south in the extended period. The mean upper flow will also
become stronger and westerly early next week as a storm system
moves across southern Canada.

Although pwats do increase slightly as another weak cold front moves
across the region Monday, most of the energy with this system will
remain in Canada. Thus, any rainfall will be isolated or scattered
in nature and no robust updrafts for strong storms. A more potent
short wave, and a stronger jet streak, will move across the upper
Midwest the middle of next week. Instability will remain weak as
another front passes through the region. However, with better jet
energy, any thunderstorms could be capable of producing strong wind

The end of next week can be characterized as cooler than normal as
the mean upper flow remains northwest. This will likely mean highs
near 80 and lows in the 60s.


Aviation...(for the 06z tafs through 06z Saturday night)
issued at 1104 PM CDT Fri Jul 20 2018

Main concern now is how extensive does stratus get tonight.
Beginning to see the first signs of this stratus showing up to
the northeast of Mille Lacs. Rap/hrrr continue to show this
stratus working toward southwest Minnesota. NAM soundings are certainly
moist in the low levels, but that moisture is relatively shallow,
so it's hard to say how widespread the stratus will become. At
either rate, lav continues to show best IFR/MVFR probs at
axn/stc/rwf, though msp and mkt could get in on the fun as well.
No rain Saturday, with morning stratus slowly lifting through the
morning. Looks like cloudiest skies will be over Minnesota, with mainly
sunny skies over WI.

Kmsp...still potential for 1k to 1.5k ft cigs to impact the
Airport between 10z and 16z Sat morning. Will have to watch how
stratus to the northeast of Mille Lacs Lake evolves.

/Outlook for kmsp/
sun...VFR. Wind NE 5-10 kts.
Mon...VFR. Slight chc -tsra. Wind vrbl becoming northwest 5-10 kts.
Tue...VFR. Wind west 5 kts.


Mpx watches/warnings/advisories...


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