Altocumulus Average Cloud Amount (%) December, January, February (1954 - 1997) Day, Ship Observations Only Global Average: 17.7 Zonal Averages 17 zones Lat.N Average 85 12.7 75 14.3 65 14.6 55 13.9 45 14.3 35 17.1 25 14.3 15 12.0 5 19.2 -5 19.6 -15 18.0 -25 17.3 -35 17.7 -45 19.7 -55 24.1 -65 23.5 -75 18.2 Grid Box Averages 393 filled boxes Box # Lat.N Lon.E Average 1 85 60 14.2 2 85 180 11.3 3 85 300 12.6 4 75 20 17.6 5 75 60 12.6 6 75 100 4.4 7 75 140 12.0 8 75 180 14.4 9 75 220 13.8 11 75 300 15.9 12 75 340 21.5 13 65 10 20.9 14 65 30 13.6 15 65 50 12.8 21 65 170 5.9 22 65 190 4.2 23 65 210 10.7 27 65 290 12.3 29 65 330 17.3 30 65 350 18.9 31 55 10 17.2 32 55 30 20.2 37 55 130 11.7 38 55 150 9.0 39 55 170 11.2 40 55 190 11.2 41 55 210 13.3 42 55 230 14.5 45 55 290 17.7 46 55 310 12.8 47 55 330 18.5 48 55 350 18.4 49 45 5 16.8 50 45 15 17.1 51 45 25 14.7 52 45 35 13.5 53 45 45 11.1 54 45 55 13.0 61 45 125 10.3 62 45 135 7.9 63 45 145 9.1 64 45 155 9.9 65 45 165 10.9 66 45 175 11.4 67 45 185 11.8 68 45 195 12.2 69 45 205 13.3 70 45 215 15.1 71 45 225 16.5 72 45 235 17.2 77 45 285 12.6 78 45 295 13.9 79 45 305 16.1 80 45 315 17.7 81 45 325 17.9 82 45 335 18.9 83 45 345 18.0 84 45 355 17.4 85 35 5 16.8 86 35 15 16.6 87 35 25 16.8 88 35 35 15.4 89 35 45 19.8 90 35 55 10.3 96 35 115 6.5 97 35 125 14.9 98 35 135 14.0 99 35 145 12.5 100 35 155 14.9 101 35 165 15.0 102 35 175 14.7 103 35 185 15.4 104 35 195 16.3 105 35 205 18.3 106 35 215 19.3 107 35 225 18.8 108 35 235 14.9 109 35 245 10.8 112 35 275 16.7 113 35 285 20.0 114 35 295 21.0 115 35 305 20.2 116 35 315 20.5 117 35 325 19.8 118 35 335 20.1 119 35 345 16.5 120 35 355 15.6 124 25 35 6.6 125 25 45 14.3 126 25 55 8.3 127 25 65 4.6 128 25 75 3.2 129 25 85 4.9 130 25 95 6.8 131 25 105 23.7 132 25 115 18.8 133 25 125 17.8 134 25 135 14.8 135 25 145 14.9 136 25 155 14.7 137 25 165 13.4 138 25 175 12.6 139 25 185 12.3 140 25 195 12.8 141 25 205 13.8 142 25 215 17.2 143 25 225 19.0 144 25 235 18.2 145 25 245 14.5 146 25 255 16.3 147 25 265 20.5 148 25 275 16.0 149 25 285 14.4 150 25 295 13.0 151 25 305 12.8 152 25 315 13.8 153 25 325 14.1 154 25 335 12.1 155 25 345 9.3 160 15 35 9.9 161 15 45 6.7 162 15 55 5.5 163 15 65 5.2 164 15 75 5.3 165 15 85 7.6 166 15 95 7.5 167 15 105 15.5 168 15 115 14.0 169 15 125 14.3 170 15 135 13.9 171 15 145 11.4 172 15 155 10.1 173 15 165 8.6 174 15 175 9.6 175 15 185 10.1 176 15 195 11.9 177 15 205 13.4 178 15 215 16.4 179 15 225 19.5 180 15 235 22.1 181 15 245 18.7 182 15 255 11.4 183 15 265 6.1 184 15 275 10.4 185 15 285 9.7 186 15 295 10.4 187 15 305 11.0 188 15 315 12.9 189 15 325 14.9 190 15 335 13.8 191 15 345 11.2 193 5 5 16.6 197 5 45 7.5 198 5 55 9.2 199 5 65 10.6 200 5 75 13.3 201 5 85 21.1 202 5 95 24.3 203 5 105 24.4 204 5 115 24.9 205 5 125 22.8 206 5 135 26.2 207 5 145 21.7 208 5 155 21.9 209 5 165 23.8 210 5 175 22.2 211 5 185 17.8 212 5 195 19.3 213 5 205 19.0 214 5 215 19.2 215 5 225 17.9 216 5 235 19.5 217 5 245 18.1 218 5 255 16.2 219 5 265 16.6 220 5 275 17.0 221 5 285 19.1 222 5 295 15.0 223 5 305 17.7 224 5 315 23.3 225 5 325 23.2 226 5 335 20.9 227 5 345 14.8 228 5 355 16.1 229 -5 5 20.5 230 -5 15 22.7 232 -5 35 12.0 233 -5 45 13.1 234 -5 55 16.7 235 -5 65 20.6 236 -5 75 25.2 237 -5 85 26.6 238 -5 95 27.8 239 -5 105 35.9 240 -5 115 38.7 241 -5 125 32.2 242 -5 135 31.9 243 -5 145 33.8 244 -5 155 29.0 245 -5 165 30.3 246 -5 175 30.9 247 -5 185 20.8 248 -5 195 15.5 249 -5 205 11.7 250 -5 215 8.0 251 -5 225 7.4 252 -5 235 8.9 253 -5 245 11.1 254 -5 255 15.0 255 -5 265 15.7 256 -5 275 19.4 257 -5 285 18.9 260 -5 315 21.3 261 -5 325 14.2 262 -5 335 11.3 263 -5 345 11.3 264 -5 355 11.9 265 -15 5 16.8 266 -15 15 23.1 268 -15 35 16.2 269 -15 45 22.4 270 -15 55 16.2 271 -15 65 16.0 272 -15 75 18.4 273 -15 85 17.3 274 -15 95 18.1 275 -15 105 17.2 276 -15 115 13.4 277 -15 125 21.2 278 -15 135 26.7 279 -15 145 22.8 280 -15 155 18.2 281 -15 165 20.1 282 -15 175 23.7 283 -15 185 26.4 284 -15 195 25.1 285 -15 205 22.5 286 -15 215 18.5 287 -15 225 14.5 288 -15 235 13.6 289 -15 245 15.8 290 -15 255 16.7 291 -15 265 16.5 292 -15 275 15.6 293 -15 285 19.8 297 -15 325 16.7 298 -15 335 11.0 299 -15 345 13.3 300 -15 355 15.9 301 -25 5 11.7 302 -25 15 15.1 304 -25 35 14.1 305 -25 45 14.8 306 -25 55 16.8 307 -25 65 16.5 308 -25 75 15.7 309 -25 85 15.0 310 -25 95 17.3 311 -25 105 17.5 312 -25 115 10.1 315 -25 145 15.4 316 -25 155 15.4 317 -25 165 16.8 318 -25 175 19.4 319 -25 185 19.5 320 -25 195 22.5 321 -25 205 24.0 322 -25 215 22.6 323 -25 225 19.9 324 -25 235 18.4 325 -25 245 15.0 326 -25 255 15.7 327 -25 265 16.0 328 -25 275 14.7 329 -25 285 19.9 332 -25 315 23.9 333 -25 325 21.1 334 -25 335 16.8 335 -25 345 13.4 336 -25 355 15.9 337 -35 5 15.6 338 -35 15 10.3 339 -35 25 14.0 340 -35 35 16.9 341 -35 45 16.9 342 -35 55 16.9 343 -35 65 17.8 344 -35 75 17.7 345 -35 85 19.7 346 -35 95 19.7 347 -35 105 19.8 348 -35 115 13.8 349 -35 125 19.1 350 -35 135 18.3 351 -35 145 17.0 352 -35 155 16.1 353 -35 165 18.2 354 -35 175 18.8 355 -35 185 20.0 356 -35 195 21.0 357 -35 205 21.6 358 -35 215 21.9 359 -35 225 21.4 360 -35 235 20.2 361 -35 245 18.3 362 -35 255 18.3 363 -35 265 11.6 364 -35 275 12.1 365 -35 285 10.8 366 -35 295 12.1 367 -35 305 13.8 368 -35 315 17.0 369 -35 325 19.9 370 -35 335 20.9 371 -35 345 18.7 372 -35 355 18.6 373 -45 5 24.8 374 -45 15 22.2 375 -45 25 22.4 376 -45 35 23.2 377 -45 45 20.4 378 -45 55 19.2 379 -45 65 22.1 380 -45 75 25.0 381 -45 85 23.1 382 -45 95 18.3 383 -45 105 19.2 384 -45 115 20.4 385 -45 125 21.2 386 -45 135 22.5 387 -45 145 22.4 388 -45 155 19.4 389 -45 165 18.9 390 -45 175 19.4 391 -45 185 19.3 392 -45 195 21.5 393 -45 205 17.8 394 -45 215 19.4 395 -45 225 17.3 396 -45 235 17.6 397 -45 245 18.6 398 -45 255 15.4 399 -45 265 14.6 400 -45 275 11.3 401 -45 285 15.4 402 -45 295 13.7 403 -45 305 17.1 404 -45 315 20.5 405 -45 325 21.1 406 -45 335 17.7 407 -45 345 21.8 408 -45 355 20.8 409 -55 10 28.9 410 -55 30 24.8 411 -55 50 33.6 412 -55 70 24.3 413 -55 90 26.2 414 -55 110 21.9 415 -55 130 21.0 416 -55 150 17.9 417 -55 170 23.0 418 -55 190 22.7 419 -55 210 22.4 420 -55 230 20.7 421 -55 250 20.1 422 -55 270 16.7 423 -55 290 23.1 424 -55 310 27.1 425 -55 330 27.7 426 -55 350 30.8 427 -65 10 23.1 428 -65 30 26.2 429 -65 50 23.0 430 -65 70 20.4 431 -65 90 23.2 432 -65 110 17.3 433 -65 130 20.6 434 -65 150 22.0 435 -65 170 20.4 436 -65 190 23.1 437 -65 210 23.2 438 -65 230 17.2 439 -65 250 26.1 440 -65 270 26.9 441 -65 290 22.4 442 -65 310 35.5 443 -65 330 26.0 444 -65 350 21.6 449 -75 180 17.3 450 -75 220 13.3 451 -75 260 17.9 452 -75 300 25.8 453 -75 340 19.1