VALID 190100Z – 191200Z

…THERE IS A SLGT RISK OF SVR TSTMS FROM THE UPPER MS VALLEY TO WRN
NY…

…UPPER MS VALLEY TO LAKE WESTERN NY…

CONSIDERABLE VEERING AND WEAK LOW LEVEL CONVERGENCE APPEAR TO BE
PARTLY RESPONSIBLE FOR LACK OF STRONG CONVECTION ACROSS THE UPPER MS
VALLEY THIS EVENING. ORGANIZED DEEP CONVECTION HAS STRUGGLED TO
INTENSIFY AHEAD OF WEAK SFC LOW OVER THE ARROWHEAD OF MN BUT
APPROACHING SHORT-WAVE TROUGH IS EXPECTED TO AID DEVELOPMENT LATER
THIS EVENING NEAR THE CANADIAN BORDER.

HAVE OPTED TO LOWER SEVERE PROBS ACROSS MN/WI DUE TO THE STRUGGLING
NATURE OF THIS CONVECTION BUT TSTMS ARE STILL ANTICIPATED TO DEVELOP
SWWD ALONG THE COLD FRONT WHICH SHOULD THEN SPREAD EAST ACROSS THE
U.P. OF MI LATE TONIGHT.

DOWNSTREAM…A WELL ORGANIZED BAND OF TSTMS HAVE EVOLVED WITHIN WEAK
WARM ADVECTION ZONE ACROSS THE ERN U.P. INTO ONTARIO. THIS ACTIVITY
IS SPREADING SEWD AT ROUGHLY 35KT AND IF CONVECTION CAN REMAIN
ORGANIZED IT MAY SPREAD ACROSS LAKE ONTARIO INTO WRN NY AROUND
SUNRISE.

00Z SOUNDINGS ACROSS THE UPPER MS VALLEY INTO NRN LOWER MI REMAIN
FAVORABLE FOR MAINTENANCE OF ANY ORGANIZED BANDS OF CONVECTION THAT
EVOLVE ALONG/AHEAD OF COLD FRONT…THUS DAMAGING WINDS MAY BE THE
GREATEST SEVERE THREAT THE REST OF THE PERIOD.

..DARROW.. 07/19/2013