Statement as of 2:25 PM CDT on May 24, 2012

The NWS Storm Prediction Center has issued a

Tornado Watch for portions of 

       western and central Upper Michigan

       southeast Minnesota

       northern and western Wisconsin

       Lake Superior

Effective this Thursday afternoon and evening from 225 PM until

1000 PM CDT.

Tornadoes... hail to 2 inches in diameter... thunderstorm wind

gusts to 70 mph... and dangerous lightning are possible in these

areas.

The Tornado Watch area is approximately along and 80 statute

miles east and west of a line from 25 miles south southwest of La

Crosse Wisconsin to 40 miles northeast of Ironwood Michigan. For

a complete depiction of the watch see the associated watch

outline update (wous64 kwns wou5).

Remember... a Tornado Watch means conditions are favorable for

tornadoes and severe thunderstorms in and close to the watch

area. Persons in these areas should be on the lookout for

threatening weather conditions and listen for later statements

and possible warnings.

Discussion... thunderstorms are beginning to increase in coverage

along a cold front from srn MN into nrn IA in response to increasing

forcing ahead of a strong short wave trough approaching from the

southwest. Storms are likely to intensify into nwrn/west central WI

this afternoon as a deepening surface low moves nnewd along a

pre-existing thermal gradient... with activity progressing ewd/newd

through the evening. Although low level moisture is somewhat

marginal... strong forcing and intense vertical shear will promote

development of bowing line segments and occasional embedded

supercells with attendant threats for wind damage and a few

tornadoes.

Aviation... tornadoes and a few severe thunderstorms with hail

surface and aloft to 2 inches. Extreme turbulence and surface

wind gusts to 60 knots. A few cumulonimbi with maximum tops to

450. Mean storm motion vector 22045.

... Weiss