Hail Size Comparison Guide: From Pea to Softball
When a storm spotter says “golf ball sized hail,” or when the NWS issues a severe thunderstorm warning with a “2-inch hail threat,” what does that actually mean for your property? This guide explains the standard hail size references used by meteorologists, and what damage to realistically expect at each size.
How the SPC Measures Hail
The Storm Prediction Center records hail size in hundredths of inches. A database entry of `175` means 1.75 inches — golf ball size. This is a common source of confusion: some tools incorrectly display “175 inch hail” because they fail to convert. FindTheTornado.com always divides by 100 to display the correct decimal value.
The SPC considers hail severe when it reaches 1.00 inch (quarter size) or larger.
Hail Size Reference Chart
| Common Name | Diameter | Notes |
|————-|———-|——-|
| Pea | 0.25″ | Usually harmless. No property damage. |
| Marble | 0.5″ | Minor surface marks on soft metals. |
| Penny | 0.75″ | Window screen damage, paint chips. Below SPC severe threshold. |
| Quarter | 1.00″ | SPC “severe” threshold. Granule loss on asphalt shingles begins. |
| Half dollar | 1.25″ | Increasing shingle bruising. Soft metal dents possible. |
| Ping pong ball | 1.50″ | Significant shingle damage. Vehicle dimpling. |
| Golf ball | 1.75″ | Professional inspection strongly advised. Shingle bruising likely. Vehicle hood/roof dents. |
| Tennis ball | 2.50″ | Severe shingle and siding damage. Windshield cracking. |
| Baseball | 2.75″ | Major damage. Multiple inspection categories. Structural concerns on older roofs. |
| Grapefruit | 4.00″ | Catastrophic damage to most property types. |
| Softball | 4.50″ | Rarely observed. Catastrophic structural and vehicle damage. |
What Damage to Expect by Size
1.00″ – 1.25″ (Quarter to Half Dollar)
This is the most common “severe” hail size. From the ground, you may not see obvious damage. However, impact marks on asphalt shingles — visible as dark, circular bruises — are common. Granule loss (shingle mineral granules knocked off by hail) appears as dark patches and accumulates in gutters and downspouts.
1.50″ – 1.75″ (Ping Pong to Golf Ball)
Vehicle owners frequently notice dents on hoods, roofs, and trunks at this size. Window screens may develop holes. Gutters and downspouts typically show visible denting. Vinyl siding may crack in cold-weather events. A professional inspection is warranted.
2.50″+ (Tennis Ball and Larger)
At this size, damage is often visually obvious. Shingles may be punctured. Windshields and skylights crack. Vehicle damage is severe. Structural damage to older or damaged roofing systems is possible.
Factors That Affect Damage
Size alone doesn’t determine damage. Other factors include:
- Wind speed and direction: Hail driven by strong winds hits at an angle, concentrating damage on wind-facing surfaces.
- Hail density: Some hailstones are more solid (graupel-free) than others, affecting impact energy.
- Roof age and condition: A 5-year-old roof and a 20-year-old roof respond very differently to the same hail size.
- Duration of storm: Longer events accumulate more impacts per surface area.
Use Our Damage Calculator
Enter the hail size reported near your location into our Storm Damage Risk Calculator to get an estimate of shingle, siding, window, and vehicle risk.
Sources: SPC Storm Data, Insurance Institute for Business & Home Safety (IBHS)
*FindTheTornado.com does not perform inspections, repairs, or insurance work. All content is educational.*