National Weather Service Burlington, VT Twitter Page National Weather Service Burlington, VT Facebook Page
Local forecast by
"City, St" or zip code
 Current Hazards
 Current Conditions
 Model Data
 Weather Safety
 Contact Us
WFO BTV Top 10 Weather Events of 2000 to 2009
Main 10 9 8 7 6 5 4 3 2 1

10.) June 10th 2008 Widespread Severe Weather Outbreak (over 50 reports) with every country reporting severe weather
On June 10, 2008, a significant severe weather outbreak occurred across northern New York as well as central and northern Vermont. This outbreak featured two major rounds of severe weather, which produced over 50 severe weather reports across the Weather Forecast Office (WFO) Burlington (BTV) forecast area, with severe weather occurring in every county in our area of responsibility. The severe weather reports included numerous trees and power lines being knocked down, from damaging thunderstorm winds up to 80 mph, along with up to golf ball size hail. The widespread severe thunderstorms produced over 50,000 power outages across northern New York and Vermont during the event. Click here to view the local storm report from the National Weather Service Office in Burlington, Vermont.

The large scale pattern on June 10th featured a departing mid/upper level ridge along the eastern seaboard, which provided our region with surface temperatures well into the 80s and lower 90s, along with very high humidity levels. On June 10th Burlington reached a high temperature of 93 degrees, before the thunderstorms arrived. Meanwhile, several potent disturbances in the fast jet stream winds aloft helped to enhance a mid/upper level trough across the central Great Lakes. This energy and associated cold pocket of air at 30,000 to 35,000 feet above the surface interacted with a very moist and unstable air mass at the surface to produce several rounds of significant severe weather across the WFO BTV county warning area (CWA).

Click to enlarge
The first round of severe thunderstorms occurred between noon and 4 PM and was associated with a weak pre frontal surface trough and embedded disturbance aloft. The second round of storms occurred between 6 PM and 10 PM, which featured a sharp cold front, along with another potent disturbance in the winds aloft. This setup of two rounds of significant severe weather is unusual across our forecast area; rain-cooled air associated with the first round often stabilizes the atmosphere and limits the overall severe weather threat associated with the second round of storms.

Figure 10-1 shows a water vapor loop, along with lightning activity (indicated in red/white), and movement of several disturbances aloft (shown in red) from 1225 PM through 700 PM on June 10th. The image shows two distinct rounds of storms across our county warning area, which is shown by the lightning activity. In addition, note the significant drying/subsidence aloft across the Ohio Valley and eastern Great Lakes associated with potent short wave energy and digging mid/upper level trough.
Click to enlarge
The first line of convection produced numerous trees down across St. Lawrence County in northern New York, along with damaging winds between Shelburne and Williston, Vermont. An Automated Weather Observing Station (AWOS) at Potsdam measured a 58 mph wind gust, while winds were estimated at 70 mph at North Hero, associated with the first line of convection. In addition to the damaging thunderstorm wind gusts, one inch diameter hail was observed at Shelburne, Vermont at 225 PM.

Figure 10-2 shows a composite reflectivity radar loop from Noon through 4 PM, along with lightning activity in white. First, note the very strong storm with (65 to 70 DBZ) the purple reflectivity returns across St Lawrence County in northern New York along with the associated cloud-to-ground lightning strikes. Then notice the line redeveloping across the Champlain Valley around 2 PM with more purple returns in the reflectivity structure.
Click to enlarge
The second line of damaging thunderstorm winds and up to golf ball sized hail occurred between 6:30 and 10:00 PM. Figure 10-3 is a composite reflectivity loop with lightning from 530 PM to 10:00 PM.

Note the several embedded lines of strong to severe thunderstorms that develop across our forecast area ahead of the approaching cold front. In addition, note all the lightning activity associated with these thunderstorms.
Click to enlarge
This severe weather event on 10 June 2008 produced over 50 reports of severe weather, along with widespread power outages across northern New York as well as central and northern Vermont.

In addition, damaging hail up to golf ball size and thunderstorm wind gusts to 60 mph occurred with this significant severe weather outbreak, ranking this outbreak among the top ten weather events of the past decade across WFO BTV. The photo in figure 10-4 shows a shelf cloud structure near South Burlington, Vermont associated with strong thunderstorm wind gusts.
Click to enlarge
Figure 10-5 shows thunderstorm wind damage near Williston, Vermont on 10 June 2008.
A further analysis of this event, with details radar and pre-storm analysis can be found at the following link:

<<< Back #9 >>>
Figure 10-1: Water Vapor from 1215 PM to 700 PM on 10 June 2008
Figure 10-2: Composite Reflectivity Radar Loop from Noon through 4 PM on 10 June 2008 (Lightning Activity in White)
Figure 10-3: Composite Reflectivity Radar Loop from 5:30 through 10 PM on 10 June 2008 (Lightning Activity in White)
Figure 10-4: Shelf Cloud Structure near Overlook Park South Burlington, Vermont
Figure 10-5: Tree Damage Williston, Vermont

National Weather Service
1200 Airport Drive
S. Burlington VT 05403

Webmaster: Webmaster
Page last modified: February 20, 2010
About Us
Career Opportunities
Privacy Policy