High Level (Cirriform) Amount-When-Present (%) September, October, November (1954 - 1997) , Ship Observations Only Global Average: 34.5 Zonal Averages 17 zones Lat.N Average 85 32.8 75 43.8 65 36.7 55 36.2 45 33.9 35 32.9 25 29.5 15 33.2 5 33.6 -5 33.6 -15 30.7 -25 31.6 -35 34.4 -45 36.6 -55 42.1 -65 41.4 -75 44.7 Grid Box Averages 343 filled boxes Box # Lat.N Lon.E Average 1 85 60 24.1 2 85 180 45.7 3 85 300 24.4 4 75 20 34.4 5 75 60 37.1 6 75 100 39.3 7 75 140 44.8 8 75 180 53.0 9 75 220 49.6 10 75 260 40.0 11 75 300 39.5 12 75 340 36.4 13 65 10 32.0 14 65 30 35.1 15 65 50 36.6 20 65 150 38.3 21 65 170 34.3 22 65 190 38.0 23 65 210 34.9 25 65 250 37.2 26 65 270 41.2 27 65 290 42.5 28 65 310 35.4 29 65 330 34.2 30 65 350 35.3 31 55 10 35.1 32 55 30 40.6 37 55 130 29.0 38 55 150 34.8 39 55 170 33.2 40 55 190 32.7 41 55 210 36.3 42 55 230 33.5 44 55 270 43.9 45 55 290 40.5 46 55 310 38.9 47 55 330 40.1 48 55 350 34.3 49 45 5 32.7 50 45 15 35.2 51 45 25 39.5 52 45 35 37.2 53 45 45 33.5 54 45 55 33.3 62 45 135 34.9 63 45 145 35.0 64 45 155 32.6 65 45 165 29.7 66 45 175 31.2 67 45 185 33.5 68 45 195 34.3 69 45 205 31.9 70 45 215 32.2 71 45 225 34.9 72 45 235 33.5 77 45 285 37.8 78 45 295 37.5 79 45 305 37.6 80 45 315 39.2 81 45 325 35.3 82 45 335 34.1 83 45 345 32.6 84 45 355 32.3 85 35 5 32.4 86 35 15 33.5 87 35 25 34.6 88 35 35 33.5 90 35 55 31.4 96 35 115 38.1 97 35 125 35.5 98 35 135 34.5 99 35 145 31.9 100 35 155 31.3 101 35 165 36.6 102 35 175 32.2 103 35 185 31.9 104 35 195 32.3 105 35 205 31.3 106 35 215 30.6 107 35 225 33.8 108 35 235 32.8 109 35 245 37.7 112 35 275 35.9 113 35 285 36.4 114 35 295 35.2 115 35 305 31.6 116 35 315 33.6 117 35 325 30.7 118 35 335 32.1 119 35 345 31.5 120 35 355 31.4 124 25 35 34.8 125 25 45 40.5 126 25 55 34.3 127 25 65 32.1 128 25 75 29.0 129 25 85 30.3 131 25 105 38.6 132 25 115 34.7 133 25 125 32.5 134 25 135 27.2 135 25 145 26.7 136 25 155 27.3 137 25 165 29.0 138 25 175 28.3 139 25 185 28.4 140 25 195 30.5 141 25 205 31.1 142 25 215 30.3 143 25 225 31.2 144 25 235 26.2 145 25 245 29.3 146 25 255 30.8 147 25 265 28.4 148 25 275 27.8 149 25 285 30.1 150 25 295 29.2 151 25 305 29.2 152 25 315 28.9 153 25 325 30.3 154 25 335 33.4 155 25 345 36.4 160 15 35 35.0 161 15 45 32.0 162 15 55 30.2 163 15 65 29.7 164 15 75 35.6 165 15 85 32.6 166 15 95 33.0 167 15 105 42.6 168 15 115 36.1 169 15 125 32.8 170 15 135 31.9 171 15 145 29.5 172 15 155 33.6 173 15 165 35.8 174 15 175 33.4 175 15 185 34.1 176 15 195 36.5 177 15 205 34.4 178 15 215 29.3 179 15 225 33.6 180 15 235 31.3 181 15 245 30.9 182 15 255 30.3 183 15 265 30.3 184 15 275 31.0 185 15 285 33.1 186 15 295 29.7 187 15 305 30.1 188 15 315 33.6 189 15 325 38.4 190 15 335 43.3 191 15 345 43.5 193 5 5 36.8 197 5 45 26.5 198 5 55 28.9 199 5 65 31.9 200 5 75 35.8 201 5 85 35.7 202 5 95 40.9 203 5 105 42.2 204 5 115 39.9 205 5 125 37.9 206 5 135 35.3 207 5 145 31.5 208 5 155 32.2 209 5 165 39.3 210 5 175 32.5 211 5 185 29.9 212 5 195 34.5 213 5 205 31.5 214 5 215 29.6 215 5 225 26.5 216 5 235 22.3 217 5 245 27.1 218 5 255 35.5 219 5 265 30.6 220 5 275 35.6 221 5 285 44.9 223 5 305 27.7 224 5 315 27.7 225 5 325 29.4 226 5 335 33.5 227 5 345 36.0 228 5 355 32.4 229 -5 5 37.0 230 -5 15 33.3 232 -5 35 30.8 233 -5 45 24.3 234 -5 55 30.5 235 -5 65 35.4 236 -5 75 33.8 237 -5 85 36.1 238 -5 95 40.0 239 -5 105 45.3 240 -5 115 38.8 241 -5 125 36.6 242 -5 135 35.9 243 -5 145 39.0 244 -5 155 35.3 245 -5 165 32.2 246 -5 175 29.5 247 -5 185 29.8 248 -5 195 32.3 249 -5 205 31.9 250 -5 215 28.6 251 -5 225 19.8 252 -5 235 19.0 253 -5 245 22.6 254 -5 255 24.4 255 -5 265 29.6 256 -5 275 40.2 257 -5 285 44.6 260 -5 315 27.1 261 -5 325 25.8 262 -5 335 26.6 263 -5 345 26.0 264 -5 355 29.9 265 -15 5 35.6 266 -15 15 33.6 268 -15 35 30.0 269 -15 45 26.4 270 -15 55 25.7 271 -15 65 29.5 272 -15 75 31.1 273 -15 85 30.7 274 -15 95 30.9 275 -15 105 28.7 276 -15 115 28.0 277 -15 125 31.6 278 -15 135 35.8 279 -15 145 31.6 280 -15 155 31.1 281 -15 165 31.6 282 -15 175 31.1 283 -15 185 31.7 284 -15 195 32.4 285 -15 205 30.8 286 -15 215 24.9 287 -15 225 24.2 288 -15 235 24.6 289 -15 245 25.4 290 -15 255 24.8 292 -15 275 45.4 293 -15 285 38.6 297 -15 325 29.4 298 -15 335 28.8 299 -15 345 31.9 300 -15 355 37.4 301 -25 5 31.3 302 -25 15 30.8 304 -25 35 32.1 305 -25 45 29.1 306 -25 55 25.6 307 -25 65 26.3 308 -25 75 26.5 309 -25 85 28.7 310 -25 95 29.3 311 -25 105 28.3 312 -25 115 27.5 315 -25 145 22.6 316 -25 155 28.3 317 -25 165 28.5 318 -25 175 30.5 319 -25 185 33.1 320 -25 195 37.2 321 -25 205 40.3 322 -25 215 34.3 323 -25 225 34.4 324 -25 235 33.6 325 -25 245 28.8 326 -25 255 28.2 327 -25 265 30.7 328 -25 275 30.4 329 -25 285 31.1 332 -25 315 39.4 333 -25 325 35.0 334 -25 335 30.2 335 -25 345 30.4 336 -25 355 31.0 337 -35 5 32.7 338 -35 15 31.2 339 -35 25 33.8 340 -35 35 34.5 341 -35 45 31.7 342 -35 55 30.8 343 -35 65 31.0 344 -35 75 31.8 345 -35 85 31.5 346 -35 95 30.8 347 -35 105 34.7 348 -35 115 34.5 349 -35 125 36.7 350 -35 135 37.9 351 -35 145 35.4 352 -35 155 34.0 353 -35 165 33.0 354 -35 175 29.1 355 -35 185 33.2 356 -35 195 33.2 357 -35 205 39.5 358 -35 215 44.1 359 -35 225 44.0 360 -35 235 35.0 364 -35 275 35.4 365 -35 285 36.3 366 -35 295 40.3 367 -35 305 35.4 368 -35 315 35.5 369 -35 325 31.9 370 -35 335 34.3 371 -35 345 34.7 372 -35 355 34.2 379 -45 65 40.8 380 -45 75 40.2 386 -45 135 38.2 387 -45 145 39.8 388 -45 155 38.0 389 -45 165 35.1 390 -45 175 31.7 391 -45 185 35.0 392 -45 195 31.9 393 -45 205 35.4 400 -45 275 35.2 401 -45 285 39.5 402 -45 295 35.9 403 -45 305 37.4 404 -45 315 35.5 405 -45 325 40.3 414 -55 110 42.4 416 -55 150 54.5 417 -55 170 40.5 423 -55 290 37.1 424 -55 310 39.1 425 -55 330 39.3 429 -65 50 44.9 430 -65 70 34.1 432 -65 110 34.0 435 -65 170 50.3 441 -65 290 43.5 442 -65 310 40.8 449 -75 180 44.7