National Weather Service Forecast Office

Microburst Winds Town of Seneca, Ontario County
July 20, 2006

On Thursday evening July 20, 2006 thunderstorms developed along lake breeze boundaries in a warm, moist unstable air mass. While most of the storms only produced heavy rains (up to 2 inches in less than an hour in some parts of the Finger Lakes), one thunderstorm over Ontario county produced a funnel cloud and strong damaging winds.

Base Reflectivity radar images from the NWS Binghamton WSR-88D at 7:18PM. The upper left image is the 0.5 degree elevation scan with the upper right, lower right and lower left images the 1.5 degree, 2.4 degree and 3.4 degree scans, respectively.

...DAMAGE SURVEYED IN ONTARIO COUNTY...

A NATIONAL WEATHER SERVICE SURVEY TEAM LOOKED OVER DAMAGE IN THE TOWN OF SENECA IN ONTARIO COUNTY FROM THUNDERSTORMS WHICH MOVED ACROSS THE COUNTY THURSDAY EVENING JULY 20.

BASED ON THE INFORMATION GATHERED THE NATIONAL WEATHER SERVICE HAS DETERMINED THE DAMAGE IS CONSISTENT WITH STRAIGHT LINE WINDS. ALTHOUGH SEVERAL WITNESSES REPORTED SEEING A FUNNEL.

IN AN AERIAL SURVEY...IT WAS DETERMINED THAT THE MAIN DOWNBURST OCCURRED JUST EAST OF WHITNEY ROAD BETWEEN COUNTY ROUTE 4 AND ROUTE 5 AND 20. ALONG COUNTY ROUTE 4...BETWEEN WHITNEY AND GATES ROADS ...A GRAIN SILO WAS DESTROYED...SHINGLES WERE TORN OFF A HOUSE AND NUMEROUS TREES WERE DOWNED.

ALONG ROUTE 5 AND 20...AGAIN BETWEEN WHITNEY AND GATES ROAD...A BARN WAS DESTROYED AND A HOME LOST SIDING AND INSULATION. SOME PIECES OF PLYWOOD AND INSULATION WERE CARRIED UP TO 1000 YARDS DOWNWIND. DAMAGE CONTINUED TO THE SOUTH FOR ABOUT A HALF MILE ALONG NUMBER NINE ROAD WHICH INCLUDED MINOR ROOF DAMAGE TO A HOME...A DESTROYED SHED AND NUMEROUS DOWNED TREES.

LARGE HAIL WHICH ACCOMPANIED THE STORM PELTED CROPS IN THE AREA. ACRES OF CORN AND SQUASH WERE RUINED. THE AERIAL SURVEY ALSO REVEALED DAMAGE TO CORN FIELDS EAST OF SUTTON ROAD...FLATTENED AND LYING IN AN EASTERLY DIRECTION.

THE TOTAL DAMAGE AREA ENCOMPASSED ABOUT FOUR SQUARE MILES. WIND SPEEDS WERE ESTIMATED AROUND 80 MPH.

THE NATIONAL WEATHER SERVICE PARTNERED WITH THE ONTARIO COUNTY EMERGENCY MANAGEMENT OFFICE AND MERCY FLIGHT TO COMPLETE THE AERIAL AND GROUND SURVEYS.

$$

LEVAN

Storm Photos....Click the thumbnail to see a larger image

Acres of corn were destroyed	Small squash shows the affects of the hail	Several acres of squash were destroyed

Trees down on the south side of Route 5 & 20 between Savage and Number Nine Roads	Barn destroyed on the north side of Route 5& 20 between Whitney and Gates Roads	Numerous trees and branches were downed throughout the 4 square mile damage area

Corn downed on the west side of Number Nine Road	A silo on County Road 4 between Whitney and Gates Roads was destroyed	Roofing shingles were stripped off this house on County Road 4 between Whitney and Gates Roads