A pair of back-to-back nor'easters is revving up to hit the East Coast on the official start of spring, when they'll merge into the fourth storm to slam the region in a month.
The National Weather Service said Monday the bulk of the dangerous, wind-driven snow and sleet is expected to wallop New Jersey, Maryland, Delaware and parts of eastern Pennsylvania before heading off to Nantucket Island early Thursday. Hazardous road conditions and school closures are possible as early as Wednesday in Pittsburgh, where meteorologist Rich Redmond said as much as 5 inches of snow could fall.
"Being that it's middle of March, temperatures are warmer than say they'd be in January so that will have an effect on how much snow actually falls because with warmer temperatures the snow cannot accumulate as much," Redmond said.
*Updated on March 20 at 3:21 p.m.
The Pittsburgh area has seen 2 inches of snow this March and below-average temperatures.
Sleet and freezing rain are expected to start falling Tuesday, the first day of spring. By Wednesday, the East Coast could receive between 6 and 9 inches of snow, with some areas getting nearly a foot.
Officials warned widespread power outages would be possible east of Pittsburgh, especially Wednesday, as snow starts falling as fast as 3 inches an hour and gusts rise to 35 mph in some areas.
The area is under a winter weather advisory until 8 p.m. Wednesday night.
The Pennsylvania Turnpike has announced a ban on certain types of trucks, recreational vehicles and trailers due to the approaching storm.
Officials said vehicles being banned as of 8 p.m. Tuesday are empty straight CDL-weighted trucks, double trailers, tractors hauling empty trailers, and any trailers pulled by motorcycles, passenger vehicles, pickup trucks or sport utility vehicles. Also banned as of 8 p.m. Tuesday are all motorcycles and all recreational vehicles.
Turnpike officials said a comprehensive commercial vehicle ban or speed restrictions could be imposed as storm conditions develop.
The Pennsylvania Department of Transportation has announced similar restrictions on some interstates in the commonwealth, as well as some speed restrictions. The Department of Transportation says that the restrictions are in place "as long as conditions warrant."
*This post was updated to include Turnpike and Pennsylvania Department of Transportation road restrictions.
WESA's Adelina Lancianese contributed to this report.