Derecho or not, storm left its mark
Scientists see evidence of 100 mph wind gust in Rensselaer County
To really grasp what happened last Wednesday afternoon, you may want to go to 42.912183 by -73.453227 degrees latitude and longitude, which is in a rural part of Rensselaer County.
Those are the coordinates that National Weather Service scientists used when they observed “steel girders holding up a large billboard bent to the point that the billboard was almost horizontal with the ground, structural damage to a saw mill, numerous power poles leaning, and numerous trees uprooted,” according to their preliminary observation after the storm.
The Times Union found some of the conditions scientists found, as a billboard's metal supports are still left crunched and twisted on Route 7 in Valley Falls.
Those conditions suggest a gust of 100 mph likely tore through there at 3:56 p.m.
Post-storm damage assessments like that are used by weather scientists in deciding whether Wednesday’s mess, which led to countless downed trees and a days-long
power outage across the Capital Region, was an actual derecho, or weather phenomenon that almost always brings a good deal of wreckage or worst.
As of Friday, officials at the National Weather Service’s Norman, Oklahoma headquarters were still compiling data on whether the storm was a derecho — which would be a wind swath at least 250 miles wide with gusts of 58 mph along most of the length and separated by gusts of 75 mph or more.
The severe thunderstorm started around Syracuse and pushed east through to Boston, causing more than 200,000 customers in New York to lose power. Sunday afternoon crews were still working to restore the last 800 or so customers who had gone without power for four days, most of whom were in Albany and Colonie. All power was expected to be restored by Sunday evening.
Regardless of what meteorologists find, the storm had the characteristics of an unusually fearsome weather phenomenon which, while more common in the Great Plains, isn’t unknown in the Northeast.
“It’s a really interesting case,” said Jerald Brotzge, program manager for the NYS Mesonet, the statewide grid-like system of weather observatories based at the University at Albany.
A derecho, he said, begins when a cluster of thunderstorms with cold air aloft begins moving forward pushing against warmer air below. Under the right conditions that can create a “bubble” of cold air, rain and hail that can drop and push hard against the warm air below, creating the strong winds, Brotzge explained.
If this is classified as a derecho, or even if it wasn’t, the storm was unusual for October, said Brotzge. Storm watchers like Brotzge and the National Weather Service knew that a bad storm was coming and put out warnings as it developed near Syracuse.
And while derechos are large, the destructiveness can be hard to pinpoint. Wednesday's storm caused havoc because it blasted through the populated Capital Region where there are lots of residential neighborhoods and above-ground power lines.
A similar storm tore through the Adirondacks in 1995 killing five people, knocking out power for roughly 300,000 customers and leveling about 900,000 acres of trees. The Ontario-adirondack derecho, as it was later named, occurred during a July heat wave that sparked a series of derechos nationwide.
This past week's storm also blew around a 727 plane parked at the Syracuse airport and tore the roof off a Holyoke, Mass., apartment building.
Times Union meteorologist Jason Gough noted in a video that there are several types of derechos, some of which can travel 1,000 miles. “That line was [tearing ] through here,” he said of the line of thunderstorms that rolled through the region at around 60 mph.
Wednesday ’s storm in the Capital Region and beyond also led to at least two deaths — a motorist hit by a falling tree in Clifton Park and a golf pro in Great Barrington who was also struck by a tree while trying to make sure people had gotten to safety.
Are we going to see more derechos, perhaps due to climate change? That’s not yet known, said Brotzge, but there has been a long-term increase over 50 years of heavy rain events in the Northeast.
Other potential winds on Wednesday included an estimated 90 mph gust in Pittstown and an 80 mph one in Root, Montgomery County, noted Joe Villani, a meteorologist for the National Weather Service in Albany.
The highest recorded gust from the storm, or one that was physically measured on a device like an anemometer or wind gauge, was 67 mph at the Albany International Airport.
Regardless of whether Wednesday ’s storm was deemed a derecho or not, Villani, like Brotzge, said it was unusually ferocious. “It’s still safe to say that it was a very unusual and high-end wind damage storm,” he said.