Total Cloud Cover Average Cloud Amount (%) September, October, November (1954 - 1997) Night, Ship Observations Only Global Average: 68.9 Zonal Averages 17 zones Lat.N Average 85 81.9 75 83.6 65 80.8 55 78.4 45 74.4 35 63.8 25 55.3 15 58.5 5 65.9 -5 59.4 -15 62.5 -25 66.5 -35 71.6 -45 78.6 -55 85.4 -65 85.5 -75 73.4 Grid Box Averages 386 filled boxes Box # Lat.N Lon.E Average 1 85 60 83.5 2 85 180 82.2 3 85 300 79.4 4 75 20 85.5 5 75 60 86.5 6 75 100 85.1 7 75 140 84.4 8 75 180 83.1 9 75 220 81.8 10 75 260 80.9 11 75 300 74.0 12 75 340 85.6 13 65 10 79.3 14 65 30 80.1 15 65 50 81.6 16 65 70 86.2 20 65 150 74.5 21 65 170 76.3 22 65 190 85.6 23 65 210 74.5 25 65 250 82.6 26 65 270 81.3 27 65 290 80.5 28 65 310 74.6 29 65 330 81.3 30 65 350 81.8 31 55 10 71.8 32 55 30 69.9 38 55 150 70.1 39 55 170 76.8 40 55 190 84.2 41 55 210 80.2 42 55 230 77.9 44 55 270 81.7 45 55 290 76.8 46 55 310 79.8 47 55 330 82.0 48 55 350 75.8 49 45 5 49.8 50 45 15 43.8 51 45 25 47.5 52 45 35 50.3 53 45 45 54.5 54 45 55 43.0 62 45 135 45.8 63 45 145 64.6 64 45 155 77.8 65 45 165 82.1 66 45 175 83.4 67 45 185 82.9 68 45 195 82.3 69 45 205 80.7 70 45 215 80.8 71 45 225 78.4 72 45 235 66.5 77 45 285 57.7 78 45 295 63.3 79 45 305 72.6 80 45 315 77.7 81 45 325 76.8 82 45 335 76.7 83 45 345 73.2 84 45 355 66.8 85 35 5 49.5 86 35 15 42.3 87 35 25 33.9 88 35 35 29.4 90 35 55 40.4 96 35 115 36.8 97 35 125 57.0 98 35 135 62.3 99 35 145 69.8 100 35 155 73.1 101 35 165 71.6 102 35 175 71.9 103 35 185 74.1 104 35 195 72.3 105 35 205 71.8 106 35 215 70.8 107 35 225 71.2 108 35 235 61.9 109 35 245 53.9 112 35 275 53.2 113 35 285 58.3 114 35 295 64.6 115 35 305 62.5 116 35 315 61.2 117 35 325 61.9 118 35 335 63.9 119 35 345 58.7 120 35 355 42.8 124 25 35 16.2 125 25 45 16.3 126 25 55 13.0 127 25 65 23.7 128 25 75 26.4 129 25 85 54.9 130 25 95 52.2 131 25 105 63.4 132 25 115 63.7 133 25 125 65.1 134 25 135 60.5 135 25 145 56.2 136 25 155 54.7 137 25 165 54.7 138 25 175 56.2 139 25 185 57.6 140 25 195 56.6 141 25 205 56.6 142 25 215 62.0 143 25 225 71.4 144 25 235 74.1 145 25 245 45.4 146 25 255 43.9 147 25 265 53.7 148 25 275 54.9 149 25 285 55.8 150 25 295 54.0 151 25 305 53.3 152 25 315 53.7 153 25 325 52.9 154 25 335 51.6 155 25 345 38.7 160 15 35 24.1 161 15 45 24.3 162 15 55 33.4 163 15 65 41.5 164 15 75 52.8 165 15 85 60.7 166 15 95 63.3 167 15 105 67.7 168 15 115 65.0 169 15 125 64.2 170 15 135 62.5 171 15 145 61.4 172 15 155 61.0 173 15 165 59.6 174 15 175 57.2 175 15 185 59.5 176 15 195 60.4 177 15 205 59.2 178 15 215 65.1 179 15 225 70.4 180 15 235 73.1 181 15 245 63.1 182 15 255 56.6 183 15 265 58.7 184 15 275 62.9 185 15 285 55.9 186 15 295 50.5 187 15 305 53.9 188 15 315 57.2 189 15 325 60.3 190 15 335 56.1 191 15 345 43.4 193 5 5 72.8 197 5 45 39.5 198 5 55 41.5 199 5 65 52.5 200 5 75 62.9 201 5 85 69.1 202 5 95 78.8 203 5 105 71.7 204 5 115 70.8 205 5 125 65.5 206 5 135 66.8 207 5 145 67.5 208 5 155 65.8 209 5 165 64.9 210 5 175 64.3 211 5 185 62.6 212 5 195 62.2 213 5 205 61.4 214 5 215 65.7 215 5 225 63.9 216 5 235 69.7 217 5 245 72.5 218 5 255 76.8 219 5 265 79.0 220 5 275 81.0 221 5 285 76.9 223 5 305 53.0 224 5 315 54.4 225 5 325 59.8 226 5 335 68.8 227 5 345 68.2 228 5 355 72.2 229 -5 5 82.4 230 -5 15 64.7 232 -5 35 37.3 233 -5 45 44.0 234 -5 55 55.5 235 -5 65 62.4 236 -5 75 67.5 237 -5 85 70.9 238 -5 95 73.8 239 -5 105 69.5 240 -5 115 50.4 241 -5 125 45.2 242 -5 135 50.8 243 -5 145 65.3 244 -5 155 65.5 245 -5 165 64.8 246 -5 175 59.0 247 -5 185 56.1 248 -5 195 48.9 249 -5 205 42.6 250 -5 215 41.1 251 -5 225 39.1 252 -5 235 40.4 253 -5 245 48.6 254 -5 255 66.8 255 -5 265 80.7 256 -5 275 86.5 257 -5 285 78.7 260 -5 315 40.5 261 -5 325 44.4 262 -5 335 50.5 263 -5 345 67.0 264 -5 355 79.4 265 -15 5 92.0 266 -15 15 66.1 268 -15 35 37.2 269 -15 45 33.7 270 -15 55 54.9 271 -15 65 61.2 272 -15 75 66.1 273 -15 85 67.8 274 -15 95 65.2 275 -15 105 55.1 276 -15 115 26.7 277 -15 125 25.5 278 -15 135 35.7 279 -15 145 48.1 280 -15 155 54.5 281 -15 165 63.1 282 -15 175 66.8 283 -15 185 64.5 284 -15 195 64.0 285 -15 205 60.0 286 -15 215 57.2 287 -15 225 49.6 288 -15 235 50.7 289 -15 245 58.7 290 -15 255 72.1 291 -15 265 82.3 292 -15 275 91.3 293 -15 285 82.5 297 -15 325 56.1 298 -15 335 61.5 299 -15 345 77.7 300 -15 355 91.6 301 -25 5 80.6 302 -25 15 55.0 304 -25 35 54.6 305 -25 45 54.5 306 -25 55 55.1 307 -25 65 61.5 308 -25 75 65.8 309 -25 85 69.7 310 -25 95 70.3 311 -25 105 66.0 312 -25 115 36.9 315 -25 145 36.5 316 -25 155 46.0 317 -25 165 57.9 318 -25 175 64.9 319 -25 185 66.5 320 -25 195 69.7 321 -25 205 71.8 322 -25 215 71.0 323 -25 225 67.2 324 -25 235 63.5 325 -25 245 59.8 326 -25 255 68.7 327 -25 265 74.5 328 -25 275 80.5 329 -25 285 77.5 332 -25 315 68.0 333 -25 325 67.0 334 -25 335 67.4 335 -25 345 71.0 336 -25 355 77.9 337 -35 5 77.6 338 -35 15 54.4 339 -35 25 60.1 340 -35 35 69.3 341 -35 45 68.9 342 -35 55 68.0 343 -35 65 72.7 344 -35 75 76.4 345 -35 85 76.9 346 -35 95 76.3 347 -35 105 75.0 348 -35 115 61.6 349 -35 125 65.7 350 -35 135 67.4 351 -35 145 62.5 352 -35 155 61.6 353 -35 165 70.7 354 -35 175 66.0 355 -35 185 69.0 356 -35 195 71.9 357 -35 205 74.9 358 -35 215 75.5 359 -35 225 73.4 360 -35 235 75.5 361 -35 245 75.2 362 -35 255 76.8 363 -35 265 81.5 364 -35 275 79.9 365 -35 285 68.2 367 -35 305 56.5 368 -35 315 65.2 369 -35 325 72.2 370 -35 335 74.3 371 -35 345 77.2 372 -35 355 77.3 373 -45 5 79.2 374 -45 15 75.3 375 -45 25 76.3 376 -45 35 80.4 377 -45 45 76.1 378 -45 55 82.0 379 -45 65 83.9 380 -45 75 81.2 381 -45 85 85.5 382 -45 95 84.0 383 -45 105 77.2 384 -45 115 78.7 385 -45 125 71.5 386 -45 135 74.7 387 -45 145 63.9 388 -45 155 75.7 389 -45 165 78.8 390 -45 175 66.8 391 -45 185 77.2 392 -45 195 78.3 393 -45 205 82.1 394 -45 215 80.3 395 -45 225 86.6 396 -45 235 84.2 397 -45 245 84.6 398 -45 255 89.4 399 -45 265 83.0 400 -45 275 81.8 401 -45 285 76.2 402 -45 295 57.1 403 -45 305 57.8 404 -45 315 73.2 405 -45 325 77.3 406 -45 335 84.8 407 -45 345 86.1 408 -45 355 84.1 409 -55 10 88.2 410 -55 30 90.5 411 -55 50 89.1 412 -55 70 87.7 413 -55 90 90.8 414 -55 110 85.8 415 -55 130 84.7 416 -55 150 87.6 417 -55 170 86.5 418 -55 190 77.8 419 -55 210 82.0 420 -55 230 89.3 421 -55 250 89.1 422 -55 270 84.6 423 -55 290 75.4 424 -55 310 79.0 425 -55 330 80.6 426 -55 350 87.2 429 -65 50 82.5 430 -65 70 80.8 431 -65 90 84.1 432 -65 110 84.3 433 -65 130 85.9 434 -65 150 89.9 435 -65 170 90.5 436 -65 190 89.4 441 -65 290 83.8 442 -65 310 89.8 443 -65 330 84.6 444 -65 350 78.3 449 -75 180 74.0 453 -75 340 72.4