Sunday's winds reached 80-90 mph in Mont. Co.
Winds that accompanied Sunday's frontal passage in Montgomery County reached hurricane force - as high as 80 to 90 mph in some narrowly focused locations, according to the National Weather Service. And the area sustained widespread wind speeds of 60 to 75 mph.
The estimates came last night with a NWS report on some of the damage done in Montgomery County. The survey concluded that the damage was done by strong straight-line winds, and not a tornado. Here is a summary of the report:
(SUN PHOTO: Amy Davis)
"TWO SURVEY TEAMS FOCUSED ON DAMAGE IN WEST CENTRAL MONTGOMERY COUNTY
BOUNDED BY AN AREA EAST OF SENECA CREEK...SOUTH OF DARNESTOWN
ROAD...WEST OF INTERSTATE 270 AND ALONG AND NORTH OF RIVER ROAD.
WIDESPREAD DAMAGE TO LARGE HARDWOOD AND SOFTWOOD BRANCHES AND LIMBS
WAS NOTED THROUGHOUT THE SURVEYED AREA. MORE SPORADIC BUT
CONCENTRATED DAMAGE TO ENTIRE TREES ALSO WAS OBSERVED...CONSISTING
LARGELY OF UPROOTED OR SNAPPED PINE TREES. THE MOST INTENSE DAMAGE
WAS FOUND IN THE POTOMAC CHASE ESTATES AND ALONG TRAVILAH ROAD...
WHERE HARDWOOD AND SOFTWOOD TREES WERE SNAPPED 30 TO 50 FEET OFF
THE GROUND. FALLEN TREES AND LIMBS WERE TO BLAME FOR BRINGING DOWN
UTILITY LINES AND POLES THROUGH MUCH OF THE AREA.
"ANOTHER SURVEY TEAM FOCUSED ON DAMAGE IN THE ROCKVILLE...DERWOOD...
ASPEN HILL AND GLENMONT AREAS. SPORADIC YET INTENSE AREAS OF WIND
DAMAGE WERE NOTED...WITH LARGE HARDWOOD TREES UPROOTED AND
NUMEROUS LARGE LIMBS BROKEN ON BOTH HARDWOOD AND SOFTWOOD TREES.
MANY OF THESE LARGE LIMBS FELL ONTO POWER LINES AND ACROSS
NEIGHBORHOOD ROADS...MAKING ROADS IMPASSABLE. OF PARTICULAR
INTEREST WAS DAMAGE TO A LARGE CONTAINER CRANE LOCATED AT THE
MONTGOMERY COUNTY TRANSFER STATION IN DERWOOD. THE CRANE WAS
INSTALLED ON A TRACK THAT WAS ORIENTED FROM NORTHWEST TO SOUTHEAST
SUCH THAT THE HORIZONTAL MEMBER OF THE CRANE FACED TOWARD THE
NORTHWEST. WINDS ORTHOGANAL TO THE HORIZONTAL MEMBER OF THE CRANE
LIKELY PRODUCED SUFFICIENT BEARING LOAD FORCE TO PUSH THE UNSECURED
CRANE ALONG ITS TRACK BEFORE CAUSING IT TO TOPPLE DOWN A HILL
ADJACENT TO THE TRANSFER STATION.
"IN SUMMARY...ALL DAMAGE SURVEYED IN MONTGOMERY COUNTY WAS CONSISTENT
WITH VERY STRONG THUNDERSTORM OUTFLOW STRAIGHT LINE WIND. WIDESPREAD
WINDS OF 60 TO 75 MPH WERE ASSESSED...WITH SPORADIC NARROW FOCUSED
SWATHS OF 80 TO 90 MPH WINDS."
BOUNDED BY AN AREA EAST OF SENECA CREEK...SOUTH OF DARNESTOWN
ROAD...WEST OF INTERSTATE 270 AND ALONG AND NORTH OF RIVER ROAD.
WIDESPREAD DAMAGE TO LARGE HARDWOOD AND SOFTWOOD BRANCHES AND LIMBS
WAS NOTED THROUGHOUT THE SURVEYED AREA. MORE SPORADIC BUT
CONCENTRATED DAMAGE TO ENTIRE TREES ALSO WAS OBSERVED...CONSISTING
LARGELY OF UPROOTED OR SNAPPED PINE TREES. THE MOST INTENSE DAMAGE
WAS FOUND IN THE POTOMAC CHASE ESTATES AND ALONG TRAVILAH ROAD...
WHERE HARDWOOD AND SOFTWOOD TREES WERE SNAPPED 30 TO 50 FEET OFF
THE GROUND. FALLEN TREES AND LIMBS WERE TO BLAME FOR BRINGING DOWN
UTILITY LINES AND POLES THROUGH MUCH OF THE AREA.
"ANOTHER SURVEY TEAM FOCUSED ON DAMAGE IN THE ROCKVILLE...DERWOOD...
ASPEN HILL AND GLENMONT AREAS. SPORADIC YET INTENSE AREAS OF WIND
DAMAGE WERE NOTED...WITH LARGE HARDWOOD TREES UPROOTED AND
NUMEROUS LARGE LIMBS BROKEN ON BOTH HARDWOOD AND SOFTWOOD TREES.
MANY OF THESE LARGE LIMBS FELL ONTO POWER LINES AND ACROSS
NEIGHBORHOOD ROADS...MAKING ROADS IMPASSABLE. OF PARTICULAR
INTEREST WAS DAMAGE TO A LARGE CONTAINER CRANE LOCATED AT THE
MONTGOMERY COUNTY TRANSFER STATION IN DERWOOD. THE CRANE WAS
INSTALLED ON A TRACK THAT WAS ORIENTED FROM NORTHWEST TO SOUTHEAST
SUCH THAT THE HORIZONTAL MEMBER OF THE CRANE FACED TOWARD THE
NORTHWEST. WINDS ORTHOGANAL TO THE HORIZONTAL MEMBER OF THE CRANE
LIKELY PRODUCED SUFFICIENT BEARING LOAD FORCE TO PUSH THE UNSECURED
CRANE ALONG ITS TRACK BEFORE CAUSING IT TO TOPPLE DOWN A HILL
ADJACENT TO THE TRANSFER STATION.
"IN SUMMARY...ALL DAMAGE SURVEYED IN MONTGOMERY COUNTY WAS CONSISTENT
WITH VERY STRONG THUNDERSTORM OUTFLOW STRAIGHT LINE WIND. WIDESPREAD
WINDS OF 60 TO 75 MPH WERE ASSESSED...WITH SPORADIC NARROW FOCUSED
SWATHS OF 80 TO 90 MPH WINDS."
Comments
I back up to Travilah Road and at first I was convinced it was a tornado. I heard the "freight train" and then watched a phone pole get snapped in half. Very unusual for a T'storm
Posted by: Wick | July 27, 2010 1:53 PM
We were lucky, (glen park section of Rockville/Potomac,) An oak tree belonging to our back neighbor fell across our backyard shearing half of our 70 ft tall oak, while chopping the heads off two younger trees. Fortunately for us the trees fell diagonal to the house with top leaves and branches brushing across. The arborist says neighbors tree had termite damage in the middle. But the tree had leaves. Surprisingly, I have been told that all the clean up and cutting of our now damaged trees and neighbors fallen tree is our responsibility and the neighbor need not be bothered!! Almost every other year I spend 600 to 700 dollars trimming trees and branches in my backyard...and now it is someone else's tree that is going to cost me 3000 dollars of cleanup and loss of my own healthy trees....what kind of law is that?
Posted by: sukirti | July 29, 2010 6:55 PM