Listen 5 min
Share
Comment on this story Comment
* Wind advisory for much of region 8 a.m. to 8 p.m. Saturday | Tropical storm warning for St. Mary’s and Calvert counties *
Saturday is not your day for outdoor plans in the D.C. area, and Sunday may not be great either.
Fast, informative and written just for locals. Get The 7 DMV newsletter in your inbox every weekday morning. ArrowRight
There is high confidence that Tropical Storm Ophelia will bring a prolonged period with waves of moderate to heavy rain and strong, gusty winds Friday night through Saturday night, although a decrease in the rain is possible late Saturday morning into early afternoon.
Moderate rain could continue into Sunday morning, tapering off by Sunday afternoon.
This won’t be a crippling storm for the D.C. region, but it could make for dangerous driving conditions during the periods of heaviest wind-swept rain, and there could be spotty downed trees and scattered power outages. The heavy rain will loosen soils, meaning tree roots will gradually become less anchored to the ground.
Advertisement
Conditions may be most turbulent across the region late Saturday afternoon into the night.
Because it has been rather dry lately, widespread flooding because of heavy rainfall is not expected, but localized flooding could occur in areas of poor drainage and near small streams. Areas that typically flood during heavy rain are most vulnerable.
Coastal flooding is a more serious concern for areas along the Tidal Potomac and shores of the Chesapeake Bay as the storm pushes a surge of water northward. This is especially true near high tide. Areas that typically flood during major coastal storms, including Old Town Alexandria, Southwest Washington, Annapolis and Baltimore, are at risk.
In Virginia, Gov. Glenn Youngkin (R) declared a state of emergency to activate its emergency support team.
“We want to ensure that all communities, particularly those with the greatest anticipated impact, have the resources they need to respond and recover from the effects of this storm,” Youngkin said in a statement.
Storm timeline
Friday 8 p.m. to midnight: Light rain arrives from south to north. Winds 15-20 mph, gusts to near 30 mph. Confidence: Medium-High Saturday 12 a.m. to 9 a.m.: Periods of moderate to heavy rain. Winds 20-25 mph, gusts to 30-35 mph. Confidence: Medium-High Saturday 9 a.m. to 2 p.m.: Steady rain, or just occasional lighter showers? Winds 20-25 mph, gusts to 30-35 mph. Confidence: Low-Medium Saturday 2 p.m. to Sunday 5 a.m.: Periods of moderate to heavy rain. Winds 20-30 mph, gusts to 30-45 mph. Confidence: Medium-High Sunday 5 a.m. to 2 p.m. Occasional light to moderate showers possible. Winds 10-20 mph, gusts to 20-30 mph. Confidence: Medium
It will be cool and raw both Saturday and Sunday, with high temperatures in the upper 50s to mid-60s.
Advertisement
Some thunder could accompany waves of heavy rain Saturday afternoon and night, especially south and east of Washington. There’s an outside chance of a couple brief tornadoes in Southern Maryland and Virginia’s Northern Neck, embedded within areas of heavy rain.
Share this article Share
Rainfall forecast
Light rain should move into the area Friday evening from south to north, with periods of moderate to heavy rain after midnight. The most uncertain portion of the forecast is late Saturday morning into early afternoon. That’s when we could see a period of lighter rain or even some breaks due to temporarily drier air. More waves of moderate to heavy rain are likely from midafternoon Saturday through late Saturday night. Lighter showers could linger at times on Sunday.
Rainfall totals of 1.5 to 4 inches are likely with localized amounts up to around 5 inches; the highest totals are probable south and east of Washington. Here are the rainfall amounts predicted by various models:
Advertisement
American (GFS): 1.2 inches German (ICON): 1.56 inches European (ECMWF): 1.86 inches Canadian (GEM): 2.3 inches NAM and high-resolution NAM: 2.5 inches High-resolution Canadian (RGEM): 2.67 inches
Wind forecast
The breeze starts to pick up Friday evening with gusts near 30 mph, increasing to near 35 mph overnight through midday Saturday. The strongest winds should blow Saturday afternoon and night.
In the immediate D.C. area, winds during that time should be sustained at 20-30 mph with gusts near 40-45 mph. They’ll be stronger in our eastern counties adjacent to the Chesapeake Bay, sustained at 25-35 mph with gusts near 45-55 mph. And weaker in our western counties (Loudoun, Fauquier and points west), sustained at 15-25 mph with gusts near 35 mph.
“Gusty winds and a saturated ground may cause downed trees and power outages, especially along the immediate western shoreline of Maryland,” the National Weather Service wrote.
Flooding potential
The rain shouldn’t be heavy enough to cause widespread flooding, especially because much of the region is in a drought or at least running below normal for precipitation. “However, the typical more vulnerable urbanized areas as well as quick responding creeks and small streams could see some flooding,” the Weather Service said.
Advertisement
It’s a different story for shoreline locations including Old Town Alexandria, the Southwest Waterfront and Annapolis, where minor flooding is likely, and moderate flooding is possible, due to an extended period of onshore winds from the northeast that is likely to push tides 1 to 3 feet higher than normal. Tidal sites in Southern Maryland, especially in St. Mary’s County, could see “moderate to even major flood stages during the day on Saturday and into early Sunday,” the Weather Service said.
Here are the times of high tide:
Old Town Alexandria: Saturday 2:20 a.m. and 3:13 p.m.; Sunday 3:30 a.m. Southwest Waterfront: Saturday 2:19 a.m. and 3:04 p.m.; Sunday 3:27 a.m. Annapolis: Saturday 12:09 a.m. and 11:04 a.m.; Sunday 1:13 a.m. Baltimore Inner Harbor: Saturday 1:15 a.m. and 1:11 p.m.; Sunday 2:17 a.m.
Jason Samenow contributed to this report.
Share
Comments
Loading...
View more