Commonly Used Hail Sizes
Pea                         0.25 inch
Half-inch                0.50 inch
Dime                      0.75 inch
Nickel                    0.88 inch
Quarter                  1.00 inch
Half Dollar             1.25 inch
Ping Pong Ball      1.50 inch
Golf Ball                 1.75 inch
Hen Egg                 2.00 inch
Tennis Ball            2.50 inch
Baseball                2.75 inch
Tea Cup                 3.00 inch
Grapefruit              4.00 inch
Softball                  4.50 inch
***Please note there is no ‘marble size’ due to the multiple different sizes of marbles.***

Guidelines for Estimating Wind Speeds
30-44 mph—Whole trees in motion (light-weight loose items tossed or toppled, e.g., lawn furniture)

45-57 mph—Large trees bend; twigs, small limbs break and a few larger dead or weak branches break.  Old weak structures may sustain minor damage, loose shingles blow off.

58-74 mph—Large limbs break; shallow rooted trees pushed over.  Semi-trucks overturned.  Significant damage to weak structures, shingles and awnings removed, damage to chimneys and antennas.

75-89 mph—Widespread damage to trees with large limbs down or trees broken/uprooted.  Mobile homes pushed off foundation.  Roof may peal off industrial/commercial/warehouse buildings.

90+ mph—Many large trees broken and uprooted.  Mobile homes damaged.  Roofs partially pealed off homes and buildings.  Moving cars pushed off road.

The above information was taken directly from the National Weather Service - http://www.srh.noaa.gov/oun/stormspotting/reports.php