|
|
Beaufort
Number |
Wind
(knots) |
Desriptive
Term |
Land Observations |
Sea Observations |
| 0 |
<1 |
Calm |
Calm, smoke rises vertically |
Water calm, mirrorlike (.25 ft. waves) |
| 1 |
1-3 |
Light air |
Wind direction shown by smoke but not by windvanes |
Ripples with the appearance of scales (.5 to 1 ft. waves) |
| 2 |
4-6 |
Light breeze |
Leaves rustle; wind felt on face; windvanes moved by wind |
Small wavelets on water; crests have a glassy appearance and do not
break.
2-3 ft. |
| 3 |
7-10 |
Gentle breeze |
Leaves and twigs in constant motion; wind extends light flag |
Large wavelets; crests begin to break; maybe scattered whitecaps.
3.5 to 5 ft. |
| 4 |
11-16 |
Moderate breeze |
Wind raises dust and loose paper; small branches move |
Moderate waves; fairly frequent whitecaps 6 to 8 ft. |
| 5 |
17-21 |
Fresh breeze |
Small leafed trees begin to sway |
Moderate, longer waves; many whitecaps; chance of spray. 9.5 to 13
ft. |
| 6 |
22-27 |
Strong breeze |
Large branches in motion; phone lines whistle |
Large waves form; white foam crests everywhere; probable spray.
13.5 to 19 ft. |
| 7 |
28-33 |
Moderate gale |
Whole trees in motion; difficult to walk against wind |
Sea heaps up; white foam starts to blow in streaks. 18 to 25
ft. |
| 8 |
34-40 |
Fresh gale |
Wind breaks twigs off trees; walking impeded |
Moderately high waves with crests beginning to break into foam
that's blown in white streaks. 23 to 32 ft. |
| 9 |
41-47 |
Strong gale |
Slight damage to buildings occurs; shingles torn off roofs |
High waves; rolling seas; dense streaks of foam; wave crests begin
to topple, tumble and fall over. 29-41 ft. |
| 10 |
48-55 |
Whole gale |
Trees uprooted; considerable structural damage to buildings |
High waves with overhanging crests; sea is white. 64-72 ft. |
| 11-17 |
56+ |
Storm, Hurricane |
Widespread damage |
Huge waves; air filled with spray; little visibility
73 ft. + |
