Hail and Severe Storm Exposure in Loudoun County

The forecast office in Sterling

The National Weather Service's Baltimore/Washington Weather Forecast Office sits on the north side of Dulles Airport in Sterling. It provides forecast and warning services for 46 counties in Maryland, northern Virginia and the eastern West Virginia panhandle, plus Washington, D.C. and the city of Baltimore. When a severe thunderstorm warning pops up on your phone in Sterling, this is the office that issued it.

What counts as a severe storm

The Weather Service classifies a thunderstorm as severe when it produces wind gusts of 58 mph or more, hail one inch in diameter or larger (about quarter size), or a tornado. Those thresholds are useful for a homeowner because they line up with what can damage a roof. Gusts in that range can lift shingle tabs, break their seal and crease them. Hail of that size can knock granules loose and bruise shingles. Neither is always visible from the ground.

A local example: the 2012 derecho

On June 29, 2012, a long-lived line of severe thunderstorms called a derecho raced from the Midwest to the Mid-Atlantic coast. The Weather Service recorded a peak gust of 71 mph at Dulles Airport, next to Sterling, along with 70 mph at Reagan National and 66 mph at BWI. Storms like that are not common, but they show that eastern Loudoun can see winds well above the severe threshold.

How to look up storms near you

NOAA's National Centers for Environmental Information keeps the Storm Events Database, which records reported severe weather such as hail and thunderstorm wind events. You can search it by state, county and event type, for example Loudoun County, Virginia, and hail. The records are useful context if you are wondering whether a particular storm was serious, or if your insurer asks about the date of an event.

• Reports come from spotters, the public, emergency managers and other sources, so a storm that hit your street may or may not have a report right there.
• Hail size is usually estimated by observers, not measured at every house.
• A database entry is not proof your roof was damaged, and the absence of one is not proof it was not. The roof itself is the evidence.

After a severe storm: a Sterling checklist

1. Stay off the roof. Look from the ground and from upstairs windows.
2. Look for missing or lifted shingles, shingle pieces in the yard, dents in gutters and downspouts, and damaged vent caps.
3. Check the attic and top-floor ceilings for new stains or drips.
4. Look at soft metals and outdoor items like the air conditioner fins or mailbox. Dents there suggest hail hit the roof too.
5. Photograph everything with the date before cleanup.
6. Note the storm date and time; the Weather Service warnings and the Storm Events Database can help confirm it later.
7. If you see damage or a leak, call your insurer to ask how they want the claim started, and have a roofer assess the roof.

Wind damage and hail damage look different

Wind damage tends to show up along edges, ridges and the windward side of the roof: tabs folded back, shingles missing, or a line of creases where shingles flexed and broke their seal. Hail damage tends to be scattered across the slopes facing the storm, as dark spots where granules were knocked off, sometimes with soft bruises underneath. A roofer looking for one should check for the other, because severe storms often bring both.

Older roofs and storm damage

Sterling has many roofs in their second or third decade. Older shingles lose flexibility and their seal strips weaken, so they can be more vulnerable to wind than when they were new. That also makes insurance conversations harder, because an adjuster may weigh age and wear against storm damage. Good documentation helps: dated photos, a roofer's description of what failed, and the storm date.

What Roofing Roughnecks does after a storm

We assess the roof, document the damage to support an insurance claim, and recommend repair or replacement depending on its extent, working around your insurance timeline. Your policy and insurer decide what is covered; we do not interpret policies or promise outcomes. The division's typical Northern Virginia reference range for storm and insurance-related roofing is $3,000–$20,000, a range rather than a quote.