Update 7:10 p.m. Monday:
Hurricane Sandy has morphed into Post-Tropical Cyclone Sandy and is very close to making landfall, according to NOAA.
Sandy is expected to bring near-hurricane force winds and flood-producing rainfall through much of Tuesday. NOAA added that the most severe portion of the storm will affect the DC metro region from 6 p.m. Monday through dawn on Tuesday.
"Residents and businesses along the Potomac River...should prepare for a flood not seen since the floods of 1996," NOAA said in an advisory.
Around 7 p.m., data show about 90,000 Northern Virginia customers are without power, along with about 18,000 in Maryland's Prince George's and Montgomery counties. About 3,700 customers are without power in DC.
Virginia Gov. Bob McDonnell issued a statement encouraging Virginians to use the Virginian Disaster Relief Fund to help fellow citizens recover from Sandy. The fund is a state-managed relief vehicle allowing individual Virginians and businesses to assist in recovery efforts following major natural disasters in the commonwealth. https://payments.vi.virginia.gov/donatenow
Update 4:10 p.m. Monday:
The Office of Personnel Management (OPM) has announced that the federal government will be closed for a second day, Tuesday in response to Hurricane Sandy. More information is available on the OPM website.
Most local school districts have announced they will be closed Tuesday.
VRE travel for Tuesday is canceled. The Washington Metropolitan Area Transportation Authority (WMATA) has not made a decision yet regarding travel on Tuesday.
The National Hurricane Center is predicting Hurricane Sandy will make official landfall near Cape May, NJ, this evening. But the storm remains so large that strong winds and heavy rain are a concern hundreds of miles out in all directions.
The National Weather Service in Sterling forecast warns, "The main immediate threats for Sandy will be strong winds, resulting in widespread downed trees and power/communications outages...and heavy rains which will result in extensive flooding of local streams and creeks."
Other regional news:
Gov. McDonnell: Prep for Hurricane Sandy Power Outages
Fairfax County Urban Search and Rescue Team Departs for Hurricane Sandy Recovery Efforts
Will Hurricane Sandy Cancel Halloween?
Update: 3:15 p.m. Monday:
The Washington Metropolitan Airports Authority released this statement:
"All airlines serving Reagan National and Dulles International Airports have canceled operations until further notice due to Hurricane Sandy. However, the airports will remain open throughout this significant weather event.
"The Airports Authority strongly encourages passengers not to travel to the airports. Many food and retail concessions are closed and staffing is limited. Passengers should contact their airline directly to confirm or rebook travel."
Update 1:10 p.m. Monday:
In an updated National Weather Service weather statement, forecasters are now saying peak winds from Sandy will come in late this afternoon and last through daybreak on Wendnesday.
Putting the seriousness of the weather into perspective, Fairfax County's emergency blog posted: "Hurricane Sandy is about to get worse. Think of the derecho storm with high winds in June that lasted 24 minutes. The winds we’re about to experience beginning this afternoon are like the derecho, but they will last for 24 hours."
"The Potomac River is likey to go into flood stage beginning around Wednesday and lasting through Friday," the National Weather Service in Sterling reported.
Gov. Bob McDonnell is expected to speak at 1:15 p.m. today. Dominion Virginia Power is reporting fewer than 1,000 people without power throughout Northern Virginia. Those outages are scattered in small pockets throughout the region.
More information on power outages is available here.
Fairfax County officials have also release useful information on what to do if a tree hits your home (that is relevant for residents living outside Fairfax County, too).
Anyone in the District, Virginia or Maryland can also dial 211 for vital (non-emergency) information.
Update 11 a.m. Monday:
The maximum sustained winds in Hurricane Sandy are near 90 mph, according to the the National Hurricane Center's (NHC) 11 a.m. update.
Hurricane-force winds extend outward up to 175 miles mainly southwest of the center of the storm. Tropical-storm-force winds extend outward up to 485 miles.
The storm is moving toward the north-northwest at 18 mph and is expected to turn northwestward soon.
National Hurricane Center officials continue to expect the storm to transition into a frontal or wintertime low pressure system prior to landfall.
Sandy is "expected to bring life-threatening storm surge and coast hurricane winds," according to the NHC. It will also bring heavy appalachian snows.
Update - 9:20 a.m. Monday:
The maximum sustained winds in Hurricane Sandy are near 85 mph with higher gusts, the National Hurricane Center reported this morning.
Hurricane-force winds extend 175 from the center of the storm, which is now located over the Atlantic Ocean essentially due east of Norfolk. The storm is moving toward the north-northwest at 20 mph.
The National Weather Service in Sterling reported this morning, "Winds will increase steaily today...with the maximum wind gusts occuring late this afternoon through Tuesday morning. Generally, sustained winds of 30 to 50 mph with gusts to 60 mph can be expected across the entire area. ... Coupled with heavy rains from Sandy...the high winds will result in significant tree damage and power line damage."
The Virginia State Police and Department of Transportation are both asking residents to stay off the roads.
For updated power outage information, see "Widespread Power Outages Expected with Hurricane Sandy."
Original Post - 5:30 a.m. Monday:
The National Hurricane Center said there would be more rain and stronger winds across the District of Columbia and Northern Virginia than originally predicted.
Maximum sustained winds overnight increased to 85 mph from 75 mph, according to the National Hurricane Center's 5 a.m. statement Monday. Those winds will be slower — but still quite strong — over Northern Virginia and the District.
"Sandy is expected to transition into a frontal or wintertime low pressure system prior to landfall. However...this transition will not be accompanied by a weakening of the system...and in fact...a little strengthening is possible during this process. Sandy is expected to weaken after moving inland," according to National Hurricane Center officials.
A high wind warning is in effect from 8 a.m. Monday through 8 p.m. Tuesday. Winds will be sustained at 30 to 40 mph by 8 a.m. Monday and will increase to 35 to 45 mph during the day Monday. Wind gusts could reach up to 70 mph late Monday night into Tuesday. The earlier prediction was for gusts up to 60 mph.
Rainfall could be 5 – 10 inches in some areas, according to forecasters, up from an original prediction of 4 – 8 inches. The amount of flooding depends on many factors, including wind direction, wind speed, high tide levels and even Monday night’s full moon.
The Capital Weather Gang’s Jason Samenow wrote in a Sunday night blog post, “I’d like to stress that beyond a certain time Monday, it will probably become unsafe to be outside, either walking or driving. In the morning hours, you may be able to get around OK, but with wind-driven rain, it will be unpleasant. Some time after 2 or 3 p.m., once sustained winds reach 30-40 mph, and it’s gusting over 50 mph, I would not advise going out.”
The Washington Metropolitan Area Transportation Authority has closed Metrorail, Metrobus and other services. VRE trains are canceled for Monday, as are most local bus services. Schools across Northern Virginia and D.C. are closed Monday (Fairfax County Public Schools are also closed Tuesday; other districts will make decisions Monday as the storm progresses).
More on Hurricane Sandy:
Widespread Power Outages Expected with Hurricane Sandy
Food Safety Tips During Power Outages
Hurricane Sandy Pet Safety Tips
Local Boaters Prepare for Hurricane Sandy
Police Pass Out Flyers in Flood-Prone Huntington
Worst of Hurricane Sandy to Hit Monday Afternoon in Northern Virginia