MESOSCALE DISCUSSION 1299
   NWS STORM PREDICTION CENTER NORMAN OK
   0118 PM CDT WED JUN 27 2007
   
   AREAS AFFECTED...CNTRL ME
   
   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
   VALID 271818Z - 272015Z
   
   TRENDS ARE BEING MONITORED FOR AN INCREASING SEVERE THREAT.  IT
   APPEARS LIKELY THAT A WW WILL BE NEEDED SOMETIME LATER THIS
   AFTERNOON.
   
   DEEPENING CONVECTIVE DEVELOPMENT IS EVIDENT NEAR FRONTAL
   ZONE...WHICH HAS BECOME QUASI-STATIONARY IN EAST-WEST FASHION ACROSS
   CENTRAL MAINE.  BOUNDARY LAYER INSTABILITY IS NOT PARTICULARLY
   STRONG...WITH CAPE GENERALLY ON THE ORDER OF 1500-2000 J/KG...BUT
   INHIBITION IS BECOMING NEGLIGIBLE.  AND...ISOLATED TO WIDELY
   SCATTERED STORMS SEEM LIKELY TO DEVELOP THROUGH 19-20Z.  ALTHOUGH
   STRONGER MID/UPPER FLOW IS SHIFTING TO THE NORTHEAST OF
   REGION...30-40 KT WESTERLY 500 MB WINDS WILL STILL CONTRIBUTE TO
   FAVORABLE DEEP LAYER SHEAR FOR UPDRAFT ROTATION.  ISOLATED
   SUPERCELLS ARE POSSIBLE...WITH A RISK FOR LARGE HAIL/DAMAGING WIND
   GUSTS...PERHAPS A TORNADO.  HOWEVER...COVERAGE OF STORMS MAY REMAIN
   LIMITED UNTIL STRONGER UPPER FORCING AHEAD OF VIGOROUS ONTARIO SHORT
   WAVE TROUGH SPREAD INTO THE ST. LAWRENCE VALLEY BY/SHORTLY AFTER THE
   28/00-03Z TIME FRAME.
   
   ..KERR.. 06/27/2007
   
   
   ATTN...WFO...CAR...GYX...
   
   45457066 45897017 45456833 45186746 44556827 44386952
   44927031