Wind speed can be expressed in knots or mph 1 knot = 1.151 mph Wind direction is generally expressed in "true" degrees, but sometimes in magnetic. We sail or fly by magnetic compass. The local magnetic variation here is 11.1 magnetic so 183 degrees true would equal 194 magnetic (just add 11 degrees to true for magnetic) Wind direction is measured from where it is coming, but courses are measured in the direction we are going, so reciprocals are important for comparison. -90 -45 0 +45 +90 (outermost rows are reciprocals) 270 315 0 45 90 280 325 10 55 100 290 335 20 65 110 300 345 30 75 120 310 355 40 85 130 320 5 50 95 140 330 15 60 105 150 340 25 70 115 160 350 35 80 125 170 360 45 90 135 180 10 55 100 145 190 20 65 110 155 200 30 75 120 165 210 40 85 130 175 220 50 95 140 185 230 60 105 150 195 240 70 115 160 205 250 80 125 170 215 260 90 135 180 225 270 100 145 190 235 280 110 155 200 245 290 120 165 210 255 300 130 175 220 265 310 140 185 230 275 320 150 195 240 285 330 160 205 250 295 340 170 215 260 305 350 180 225 270 315 360 190 235 280 325 10 200 245 290 335 20 210 255 300 345 30 220 265 310 355 40 230 275 320 5 50 240 285 330 15 60 250 295 340 25 70 260 305 350 35 80 270 315 360 45 90 I have included 36 rows rather than 360 rows because it is very easy to fill in 1 to 10. You just add the same amount to both rows. The reciprocal of 95 would be 275 by example.