Severe Weather Possible Again Today/ Review Of Yesterdays Storms

Review Of Severe Weather On 7/16/09:
     Yesterday was a significant day for severe weather across our region. It was extremely busy, over a dozen severe thunderstorm warnings were issued, including two tornado warnings. Numerous reports of wind damage and large hail were received by the National Weather Service, including hail stones that tied the largest hail ever recorded in Vermont history (3 Inch Diameter). Also the National Weather Service will be conducting a survey of a Severe Thunderstorm in Orange County Vermont, that may have produced a Tornado. Official results of that survey will be available around 5PM this evening.

Wind Damage:
     Yesterday 7 reports of wind damage were received. Ranging from numerous limbs down to large trees down, to even a barn roof being blow off, in Williamstown, Vermont, Located in Orange County, where the storm survey is being conducted today.

Hail:
     The primary severe weather maker yesterday was hail, and some very large. 10 Reports of severe sized hail (three quarters of an inch or larger in diameter) were reported. 4 of those 10 hail reports were greater then one inch in diameter. Of most significance was the size of hail reported out of Northwestern Westford, in Chittenden County Vermont. Hail 3 inches in diameter, this ties the largest hail ever recorded in Vermont history, dating back to severe weather records from 1955. The last time a 3 inch hail stone was reported in Vermont, it was August 8th 1968, in Burlington, Vermont. Overall hail 2 inches in diameter or larger is rare for Vermont. The most recent large hail reported of 2 inches or greater across the region was in Swanton Village, Vermont on July 22nd, 2005, when hail 2 inches in diameter pounded the village, causing significant damage to cars. Other then that the most recent large hail was in 1988 when hail 2.5 inches in diameter fell in Rutland County Vermont. Hopefully pictures were taken of this most recent 3 inch hail stone. If I can get a picture of it, I will put it up for you all to see.

Tornadoes:
     Tornadoes are the most rare form of Severe weather in Vermont, although they are oddly becoming more frequent. What was an average of one tornado per year, seems to be increasing to 2 or 3 a year now. Although statistics still state an average of 1 per year for Vermont. It will be interesting to see what the National Weather Service finds in Orange County today. If infact a Tornado did touch down this will be the second Tornado this year in Vermont, and it will have occurred in the same county as the last Tornado occurred in.

Champlain Valley Weather Discussion:
     Once again it looks like today may be another busy day, although no massive hail, or tornadoes are expected to occur. Overall the Severe weather threat is smaller then yesterday, but the threat still does exists. Already temperatures have jumped into the lower to mid 70's across the region, and should continue to rise until they reach there highs of the upper 70's to lower 80's. Already the atmosphere is destabilizing with pockets of moderate instability across the region. A surface trough that will be approaching later this evening, should help trigger some thunderstorms, some of which could be strong to occasionally severe. Overnight these storms will transition into a heavy rain event, dropping a widespread rainfall of a half to one inch. Isolated higher amounts to near an inch and a half to two inches are possible where heavier thunderstorms persist. The possibility of localized flooding will need to be watched. Also if enough instability can form, then we may have to be under another Severe Thunderstorm Watch today. We will have to watch closely how thing evolve over the next several hours. Stay tuned for further updates!