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Hail roof damage: how it is identified, and what the storm records show for Arlington
Hail damage is identified by a pattern, not by one mark: impacts scattered at random across the roof covering, soft bruised spots, cracks, and matching dents on gutters, flashing and other soft metal nearby, with look-alikes such as edge wear and installation marks ruled out. This guide defines the terms the sources use, then reads NOAA's own hail records for Arlington County, which list 15 reports between 1996 and 2026.
- 15 hail reports for Arlington County in NOAA files, 1996 to 2026
- 1.50 in: the largest size listed, on August 11, 2004
- 1 inch: the size NWS and NSSL treat as severe
Hail damage, defined
Roofing and weather sources use a handful of precise terms, defined here first.
- Hail
- Solid ice that forms inside thunderstorm updrafts, according to NOAA's National Severe Storms Laboratory (NSSL). A hailstone must be at least 0.2 inch across. Smaller frozen pellets are graupel or sleet.
- Severe hail
- Hail the size of a quarter, 1 inch across, or larger. NSSL and the National Weather Service office for the Washington area both use that line.
- Sub-severe hail
- Stones under 1 inch. The Insurance Institute for Business and Home Safety (IBHS) studies them because they occur more frequently and may wear shingles down over time.
- Collateral evidence
- IBHS's term for spatter marks or impact dents on air conditioners, gutters, metal flashing, downspouts and patio furniture. It confirms that a hail event happened, which helps separate hail from ordinary wear.
- Random impact pattern
- One of IBHS's indicators of hail on shingles: a random pattern of impact marks on the shingles, listed after collateral evidence is found and look-alikes are ruled out.
- Bruise
- IBHS describes a bruise as a soft spot you can feel when pressing on the shingle. That is a hands-on check for whoever inspects the roof surface, not a reason for an owner to climb up.
- Hail swath
- The path hail leaves as a storm moves. NSSL says swaths range from a few acres to an area 10 miles wide and 100 miles long.
- Impact rating
- A product score from lab hail tests. IBHS says shingles it rates Good or Excellent have been tested to UL 2218 or FM 4473.
What NOAA lists for Arlington County
NOAA's National Centers for Environmental Information publishes the National Weather Service's storm reports as county records, and NSSL names that database as the official archive for hail events. We downloaded the 31 yearly detail files for 1996 through 2026 on October 26, 2026 and counted the rows with event type Hail for Arlington County.
| Date | Rows | Largest size listed | Report source listed |
|---|---|---|---|
| August 7, 2000 | 1 | 0.88 in | Emergency manager |
| May 5, 2004 | 1 | 1.00 in | Amateur radio |
| August 11, 2004 | 1 | 1.50 in | Law enforcement |
| March 20, 2005 | 1 | 0.88 in | Emergency manager |
| April 3, 2006 | 1 | 0.75 in | Amateur radio |
| August 14, 2008 | 1 | 0.75 in | Trained spotter |
| June 3, 2009 | 1 | 0.75 in | Amateur radio |
| May 14, 2010 | 1 | 1.00 in | Trained spotter |
| April 24, 2011 | 1 | 1.00 in | Public |
| June 1, 2011 | 1 | 1.00 in | NWS employee |
| April 15, 2024 | 5 | 1.25 in | Emergency manager, NWS employee, trained spotters |
Source: NOAA NCEI Storm Events detail files, Arlington County, VA, event type Hail. Sizes are as listed by the reporter.
Three things stand out. The dates fall in March, April, May, June and August, with none from September through February. Five of the 15 rows come from a single afternoon, April 15, 2024. And a row is a report, not a measurement at a particular address, so the table shows what was reported rather than every stone that fell.
Size, speed and swaths
Hail size is reported against everyday objects, and the National Weather Service office in Sterling, Virginia, publishes the comparison it uses. The table lines those objects up against the sizes in the Arlington rows above.
| Size listed | NWS comparison | Arlington County rows |
|---|---|---|
| 0.75 in | Penny or large marble | 3 |
| 0.88 in (7/8 in) | Nickel | 2 |
| 1.00 in | Quarter, the severe criterion | 7 |
| 1.25 in | Half dollar | 2 |
| 1.50 in | Walnut or ping pong ball | 1 |
Sources: NWS Baltimore/Washington hail size table; NOAA NCEI Storm Events.
Speed depends on size, and the numbers are estimates
NSSL gives expected fall speeds of 9 to 25 mph for stones under 1 inch, 25 to 40 mph for 1 to 1.75 inches, and 44 to 72 mph for 2 to 4 inches, and adds that there is much uncertainty in those figures. It also notes that recent wind-tunnel work shows natural hailstones fall more slowly than solid ice spheres would.
Surface wind changes the picture. NSSL says hail can fall at an angle or nearly sideways in strong winds, and that wind-driven hail tears up siding and breaks windows. A slope facing the wind can therefore be struck differently from the slope behind it.
Hail marks and their look-alikes
IBHS lays out a sequence: confirm the storm with collateral evidence, rule out the look-alikes, then look for the indicators on the roof covering. The two columns below follow that page.
Points toward hail
- A random pattern of impact marks across the shingles.
- Bruises, meaning soft spots felt when pressing on a shingle.
- Cracks or breaks where a stone struck.
- Ridge caps, which IBHS says are especially vulnerable on an asphalt shingle roof.
- Dents or spatter marks on air conditioners, gutters, flashing, downspouts or patio furniture.
Not hail, according to IBHS
- Granule loss along the edge of shingles, which IBHS calls natural weathering.
- Uniform wear or discoloration across a slope.
- Manufacturer defects.
- Marks left by installation, tools or other human activity.
- Granules knocked off by heavy rain.
A roof with worn edges and a dented gutter carries two stories. The dent supports a hail event and the edge wear does not, so a written finding should say which mark belongs to which story.
Why small hail still matters
Five of the 15 Arlington rows list stones under 1 inch, seven sit exactly at the 1 inch line, and IBHS has a research program on the smaller size class. Its summary page reports three findings for asphalt shingles.
- Repeated small hail causes cumulative damage and can reduce a roof's resistance to a later large-hail event.
- Sub-severe hail knocks protective granules away, exposing the asphalt to sunlight and speeding aging.
- Roofs exposed to natural weathering plus two simulated sub-severe hail events became up to ten times more susceptible to damage from later large hail than new shingles.
IBHS adds that current test standards do not assess how performance changes over time or with different concentrations of hail. For an owner, the practical reading is narrow: a storm with stones under 1 inch is a reason to keep dated photographs and have the roof surface examined, not a reason to assume harm or to rule it out.
What the research covers, and what it leaves out
IBHS says asphalt shingles are about 80% of installed US residential roofs, citing a 2019 industry estimate, and began its systematic hail research with them. It tests with laboratory-made hailstones of 1.5 and 2.0 inches and states that the lab tests do not exactly replicate natural impacts but allow relative comparison.
- Asphalt shingles: public ratings by product, with detail for dents, tears and granule loss.
- Synthetic composite shingles, low-slope metal roofing, solar panels and cladding: IBHS has run studies, and the low-slope metal work was done with the Metal Building Manufacturers Association. Several of these reports are open to IBHS members only.
- Everything else, including flat membranes and tile: the public IBHS pages read for this guide do not give identification marks or ratings, so this page does not either. Ask the roofer to name a source for any claim about your covering.
Our guides to flat roof systems, metal roofing and roofing materials describe the coverings themselves.
What to ask any roofer or inspector
Put these in writing before any hail finding is accepted, whether it comes from a roofer or from anyone else.
- Which marks did you find, on which slopes, and is there a photograph of each with a marker beside it?
- Which marks do you treat as look-alikes, and why: edge granule loss, uniform wear, installation marks?
- What collateral evidence did you find, and on which items?
- Were the ridge caps examined?
- Does your finding name the date of the storm it ties to, and where does that date come from?
- For a replacement shingle: which test, UL 2218 or FM 4473, and which IBHS rating applies to the product you quote?
- Who obtains any permit the work needs?
- What is your Virginia contractor license number, class and specialty? See how to check a license.
Roofers of Arlington installs, repairs and replaces roofs, flat and metal systems included, in Arlington and nearby. You can book a phone consultation and talk through the building before any visit.
Arlington rules that sit on top of a hail repair
Whether repairs after hail need a county permit, a historic review or an association vote depends on the building, not on the storm. The Arlington roofing hub sets out the county's permit table and historic district rules, and five guides apply them to particular buildings.
- Condo and co-op roofs: who decides and who pays for shared roofs.
- 1940s subdivision houses and slate roofs: what the historic papers say.
- Garden apartments and flat-roof apartments.
For the order of steps after a storm, the three-day cancellation rule for door-to-door sales and Virginia's emergency permit timing, see our storm damage guide. For ground-level checks, see the roof inspection guide, and for what ages a roof apart from hail, the roof lifespan guide. Neutral insurance background is on our roofing insurance page. Coverage, deductibles and reporting deadlines come from your policy, so ask your insurer.
Where each fact above comes from
Every page below was opened on October 26, 2026. The Storm Events counts were recomputed by us from the downloaded files.
- NOAA NSSL, Severe Weather 101: Hail Basics
- NOAA NSSL, Hail Types
- National Weather Service Baltimore/Washington, SKYWARN hail size
- NOAA NCEI, Storm Events detail files 1996 to 2026
- IBHS, Is It Hail Damage?
- IBHS, Impact Testing of High Concentrations of Small Hail
- IBHS, Relative Hail Impact Resistance of Asphalt Shingles
- IBHS, Hail Impact-Resistant Shingle Ratings
- IBHS, Hail Impact Performance of Low-Slope Metal Roofing
Questions people ask
How do I tell hail damage from normal shingle wear?
IBHS says to look first for collateral evidence such as dents or spatter marks on air conditioners, gutters, flashing and downspouts. Granule loss along shingle edges, uniform wear or fading, manufacturer defects and installation marks are not hail damage. Random impact marks, soft bruised spots and cracks where a stone struck do point to hail.
Can hail smaller than one inch hurt a roof?
IBHS research on sub-severe hail, meaning stones under 1 inch, found that it knocks protective granules off asphalt shingles and that repeated small-hail events add up. Roofs that had weathered and then taken two simulated small-hail events were up to ten times more susceptible to later large-hail damage than new shingles.
What is the largest hail NOAA lists for Arlington County?
In the NOAA Storm Events files for 1996 to 2026, the largest Arlington County hail report is 1.50 inches on August 11, 2004, from a law enforcement source. The next largest are two 1.25 inch reports from April 15, 2024. NOAA files are reports, so they show what was reported rather than every stone that fell.
Does a NOAA hail report prove my roof was hit?
No. Each row is a report tied to a county and a source, such as a trained spotter or an emergency manager, not a measurement at your address. NSSL says hail falls in swaths that range from a few acres to 10 miles wide, so a row is a date and size to set beside your own photographs, not proof about one roof.
Why would one street have damage and the next street not?
NSSL says hail falls in paths called swaths as the storm moves, and that stronger surface winds can drive it at an angle or nearly sideways. Both effects change which buildings and which slopes take the impacts, so a neighbor's roof is a weak guide to yours.
Is a dented gutter proof that the shingles are damaged?
IBHS calls dents on gutters, flashing and similar items collateral evidence that a hail event occurred. It then lists separate indicators for the roof covering itself: a random pattern of impact marks, bruising and cracks. Collateral dents help confirm the storm, and the roof surface still has to be examined for its own marks.
What do impact ratings on replacement shingles mean?
IBHS buys shingles at retail, strikes them with realistic hail impacts and records damage such as granule loss, dents and cracks, then publishes ratings by product. Its hail damage guide says shingles rated Good or Excellent have been tested to UL 2218 or FM 4473. Ask a roofer which test and which rating apply to any product quoted.
Who should I call first after a hailstorm?
IBHS says to call your insurance agent first, who will explain coverage and next steps, and to make temporary repairs such as tarping exposed areas. Coverage terms and reporting deadlines are set by your policy, so ask your insurer. Our storm damage guide covers the order of steps in more detail.
Talk through your roof with Roofers of Arlington
Share the address, what you are seeing on the roof and the decision you need to make. We will tell you what to expect before anything is scheduled.