Coordinating communications for severe weather response in the County Warning Area (CWA) of the NWS in Gray, ME.
When severe weather threatens Southern Maine and New Hampshire, please utilize the following guidelines to report observations to net control:
| Weather Phenomenon | Threshold | Required Information |
|---|---|---|
| TORNADO | Always Report | Persistent rotation, movement direction, visible debris or damage path |
| FUNNEL CLOUD | Always Report | Persistent rotation, movement direction, placement within the storm |
| WALL CLOUD | Wall Cloud | Persistent rotation, movement direction, placement within the storm |
| HAIL | Pea-size or larger | Report the largest size hailstone |
| WIND GUSTS | > 45 mph | Specify estimate or measurement |
| HEAVY RAIN | Rainfall >1" per/hr | How much, how quick, what you measured with |
| FLASH FLOODING | Always Report | Flooding of roads & structures, rivers outside their banks |
| STORM DAMAGE | Any Significant Impact |
|
Commonly used hail sizes are provided below. As a reminder, spotters are encouraged to report pea-sized hail or greater.
| Hail Descriptor | Diameter (Inches) |
|---|---|
| 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 |
General guidelines for estimating wind speeds are below. As a reminder, we encourage spotters to report wind gusts of 45 mph or greater.
| Wind Speed | Observable Impacts & Effects |
|---|---|
| 30-44 mph (26-39 kt) |
Whole trees in motion. Inconvenient walking into the wind. Light-weight loose objects (e.g., lawn furniture) tossed or toppled. |
| 45-57 mph (39-49 kt) |
Hardwood tree twigs and branches snap; some weakened soft trees snap or uproot. Old/weak structures (e.g., sheds, barns) may sustain minor damage (roof, doors). Buildings partially under construction may be damaged. A few loose shingles removed from houses. |
| 58-74 mph (50-64 kt) |
Large limbs break off hardwood trees; shallow rooted trees pushed over. Soft wood trees snap and uproot. Semi-trucks overturned. More significant damage to old/weak structures. Shingles, awnings removed from houses; damage to chimneys and antennas. |
| 75-89 mph (65-77 kt) |
Widespread damage to trees with large limbs down or trees broken/uprooted. Mobile homes may be pushed off foundation or overturned. Roof may be partially peeled off industrial/commercial/warehouse buildings. Some minor roof damage to homes. Weak structures (e.g., farm buildings, airplane hangars) may be severely damaged. |
| 90+ mph (78+ kt) |
Widespread areas of uprooted and snapped trees. Mobile homes damaged. Roofs partially peeled off homes and buildings. Moving automobiles pushed off the road. Barns, sheds heavily impacted. |
The NWS is especially interested in reports when snow is falling and radar echoes are not always able to detect the amount of snowfall and conditions on the ground. Precipitation types and ice accretion are also very important.