
I would call this a Force 9 on The Beaufort Wind Scale.
Going from Calm to near gale, to strong gale, violent storm, and hurricane. A visual numeric measure of the seas.
“The Gust” is in a Strong Gale.
Force 0 Less than 1 knots Calm Sea surface smooth and mirror-like Calm, smoke rises vertically
Force1 1-3 knots Light Air Scaly ripples, no foam crests
Force 2 4-6 knots Light Breeze Small wavelets, crests glassy, no breaking
Force 3 7-10 knots Gentle Breeze Large wavelets, crests begin to break, scattered whitecaps
Force 4 11-16 knots Moderate Breeze Small waves 1-4 ft. becoming longer, numerous whitecaps
Force 5 17-21 knots Fresh Breeze Moderate waves 4-8 ft taking longer form, many whitecaps, some spray
Force 6 22-27 knots Strong Breeze Larger waves 8-13 ft, whitecaps common, more spray
Force 7. 28-33 knots Near Gale. Sea heaps up, waves 13-19 ft, white foam streaks off breakers. Resistance felt walking against wind.
Force 8 34-40 knots Gale Moderately high (18-25 ft) waves of greater length, edges of crests begin to break into spindrift, foam blown in streaks
Force 9 41-47 mph Strong Gale High waves (23-32 ft), sea begins to roll, dense streaks of foam, spray may reduce visibility
Force 10 48-55 Knots Storm Very high waves (29-41 ft) with overhanging crests, sea white with densely blown foam, heavy rolling, lowered visibility
Force 11 56-63 mph Violent Storm. Exceptionally high (37-52 ft) waves, foam patches cover sea, visibility more reduced.
Force 12 64+ mph Hurricane Air filled with foam, waves over 45 ft, sea completely white with driving spray, visibility greatly reduced
The Beaufort Scale gives us a way of describing measured mean wind speeds (in numbers) with words. It was devised by Irishman Francis Beaufort in 1805, an officer in the British Royal Navy. He wanted to create a standard scale, which would allow naval officers to relate sea conditions to a mean wind speed when taking meteorological observations. If you would like to read about how the Beaufort Scale is used at sea, you can refer back to this great blog, Sea State and Swell.
Since 1805, the Beaufort Scale has been adjusted to be used over land as well. The table below describes how the Beaufort Scale relates to the winds on land. Wind speeds are given in both km/h and also knots (a unit of measurement for wind speed, often used by mariners).
Beaufort Wind Scale
Developed in 1805 by Sir Francis Beaufort, U.K. Royal Navy.
WE&P by EZorrilla.