Effective this Sunday night and Monday morning from 810 PM until
300 am EDT.

Hail to 1.5 inches in diameter... thunderstorm wind gusts to 70
mph... and dangerous lightning are possible in these areas.

The Severe Thunderstorm Watch area is approximately along and 105
statute miles east and west of a line from 40 miles north of
Burlington Vermont to 35 miles south southeast of Harrisburg
Pennsylvania. For a complete depiction of the watch see the
associated watch outline update (wous64 kwns wou5).

Remember... a Severe Thunderstorm Watch means conditions are
favorable for 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. Severe thunderstorms can and occasionally
do produce tornadoes.

Other watch information... this Severe Thunderstorm Watch replaces
Severe Thunderstorm Watch number 642. Watch number 642 will not
be in effect after 810 PM EDT. Continue... ww 640... ww 641... ww
643... ww 644...

Discussion... sctd tstms... including a few sustained storms/possible
bowing segments... expected to persist across ww through late
tonight. Mid/upr lvl winds across region... and large scale
ascent... will slowly increase as jet streak now over the cntrl
aplcns develops farther newd. Low to mid lvl lapse rates will be
weak. But presence of high pws with strengthening wind field/ascent
suggests a threat for locally dmgg wind and perhaps an isold tornado
through early Monday.

Aviation... a few severe thunderstorms with hail surface and aloft
to 1.5 inches. Extreme turbulence and surface wind gusts to 60
knots. A few cumulonimbi with maximum tops to 500. Mean storm
motion vector 24035.