Dangerous Roof Collapses Possible With Deep Snow, Rain
By By Alex Sosnowski, senior meteorologist.
February 21, 2014, 4:15:05 AM EST
While flooding is likely to be minor and sporadic through Friday, the warmup and rainfall will continue to bring the risk of leaky roofs and roof collapses into the weekend.
This risk is greatest on flat roofs.
"A deep snow varied by drifting, combined with rainfall, natural melting and blocked drainage systems on the roofs can lead to uneven weight distribution," According to Forensic Weather Expert Steve Wistar, "When this weight exceeds the design of the roof, a partial or total collapse could occur."
Property owners may want to consider removing some of the snow from the roof, only if they can do so safely. If any doubt, consult a properly-insured private contractor.
In some cases, strained roofs that survive the added weight from this week's rain could succumb to additional storms later this season.
Cold air is expected to return in stages this weekend, and additional storms with heavy snow are possible beginning next week. The return of cold air will cause slush and runoff to freeze.
The lingering snow cover and added moisture from the rainfall and additional snowstorms will carry the flooding forward through the remainder of the winter and perhaps into the spring.
As of Tuesday, Feb., 18, 2014, there was as much as 6 inches of water locked up in the snow over parts of the Upper Midwest and northern New England. Farther south in the Midwest and Northeast, there was between 1 and 3 inches of water contained within the snow on the ground.
Over a surface area of one square foot, an inch of water (approximately 10 inches of snow on average) weighs about 5.2 pounds. However, the weight of the snow can vary, depending on its water content when it first fell and how much rain it absorbed later.
Steve Wistar is one of the nation's leading experts on roof snow loads.
Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.
More Weather News
Weather News - April 25, 2019, 5:56:49 AM EDT
Those tired of the seemingly endless weather pattern bringing frequent rounds of soaking rain to the Northeast since the summer of 2018 should expect no end to the onslaught in the near future.
Weather News - April 24, 2019, 6:50:03 PM EDT
In a race against time, crews are frantically working to cover up the damaged ceiling of Notre Dame following the intense fire that set the cathedral ablaze last week.
Weather News - April 24, 2019, 2:30:42 PM EDT
A groundbreaking otherworldly recording may reveal clues into the secrets of one of our closest cosmic neighbors.
Weather News - April 24, 2019, 11:50:51 PM EDT
Travelers parked at Dallas Love Field Airport will be greeted by an unfortunate surprise when they return, after many cars in the garage were left surrounded by floodwaters following an outbreak of stormy weather overnight.
Weather News - April 24, 2019, 12:02:30 PM EDT
Big changes in the weather are expected in the days leading up to the marathon, which may impact race conditions.
Weather News - April 25, 2019, 1:21:06 AM EDT
The same storm responsible for flooding downpours and localized severe thunderstorms in Texas will gradually shift eastward and affect areas from Florida to the Carolinas at the end of this week.
Weather News - April 24, 2019, 11:32:40 PM EDT
Old Man Winter still has a few tricks up his sleeve and he will reveal one of those tricks across parts of the northern Plains and Great Lakes region in the form of snow this weekend.
Weather News - April 24, 2019, 12:05:21 PM EDT
It happened twice in the skies over the middle of the country for just a split second -- and he managed to catch both occurrences.