Beaufort scale for sea kayaking

Beaufort Scale	Windspeed (Knots)	Windspeed (MPH)	Description (Sea State)	Description in Forecasts	State of Sea
0	0	0	Calm: Sea like a mirror - nice paddling.	Calm	Calm
1	1-3	1-3	Light Air: Ripples but without foam crests.	Light	Calm
2	4-6	4-7	Light Breeze: Small wavelets. Crests do not break.	Light	Smooth
3	7-10	8-12	Gentle Breeze: Large wavelets. Perhaps scattered white horses.	Light	Smooth
4	11-16	13-18	Moderate Breeze: Small waves. Fairly frequent white horses. Getting bouncy, inexperienced paddlers should head to shore unless it's an onshore breeze.	Moderate	Slight
5	17-21	19-24	Fresh Breeze: Moderate waves, many white horses. Inexperienced paddlers will find it hard work paddling into this.	Fresh	Moderate
6	22-27	25-31	Strong Breeze: Large waves begin to form; white foam crests, probably spray. Seas getting big, rescues will be difficult. Warnings issued to small craft.	Strong	Rough
7	28-33	32-38	Near Gale: Sea heaps up and white foam blown in streaks along the wind direction. Big seas, kayaks are difficult to turn, communication very difficult.	Strong	Very Rough
8	34-40	39-46	Gale: Moderately high waves, crests begin to break into spindrift. Dangerous conditions - communication almost impossible. Rescues impractical.	Gale	High
9	41-47	47-54	Strong Gale: High waves. Dense foam along wind direction. Crests begin to roll over. Spray may affect visibility.	Severe gale	Very High
10	48-55	55-63	Storm: Very high waves with long overhanging crests. Sea surface appears white. Visibility affected. Lifeboat will have little chance of spotting you.	Storm	Very High

Sea State

Some coastal weather reports provide a brief description or a numerical code indicating the sea state. For reference, 1 meter equals 3 feet 4 inches.

• Calm: Waves under 0.5 meters
• Slight: Waves between 0.5 and 1.25 meters
• Moderate: Waves from 1.25 to 2.5 meters
• Rough: Waves ranging from 2.5 to 4 meters
• Very Rough: Waves between 4 and 6 meters
• High: Waves between 6 and 9 meters
• Very High: Waves from 9 to 14 meters
• Phenomenal: Waves exceeding 14 meters

According to the World Meteorological Organization’s sea state scale, a rating of 4 indicates a moderate sea, while 5 corresponds to rough conditions.