Altocumulus Average Cloud Amount (%) December, January, February (1954 - 1997) , Ship Observations Only Global Average: 17.5 Zonal Averages 17 zones Lat.N Average 85 12.4 75 12.6 65 13.1 55 12.3 45 13.1 35 16.0 25 13.9 15 11.9 5 19.2 -5 19.8 -15 18.2 -25 17.6 -35 17.4 -45 19.8 -55 24.0 -65 23.0 -75 19.1 Grid Box Averages 394 filled boxes Box # Lat.N Lon.E Average 1 85 60 14.2 2 85 180 10.2 3 85 300 13.0 4 75 20 15.1 5 75 60 10.3 6 75 100 3.4 7 75 140 10.1 8 75 180 13.0 9 75 220 14.5 11 75 300 15.6 12 75 340 16.6 13 65 10 18.2 14 65 30 13.4 15 65 50 11.0 21 65 170 5.0 22 65 190 4.2 23 65 210 8.4 27 65 290 12.4 29 65 330 14.7 30 65 350 16.9 31 55 10 14.6 32 55 30 19.4 37 55 130 10.2 38 55 150 8.0 39 55 170 10.3 40 55 190 10.3 41 55 210 11.9 42 55 230 12.4 45 55 290 15.0 46 55 310 11.4 47 55 330 16.5 48 55 350 15.8 49 45 5 15.5 50 45 15 15.9 51 45 25 13.4 52 45 35 12.1 53 45 45 11.7 54 45 55 10.9 61 45 125 9.1 62 45 135 7.1 63 45 145 8.4 64 45 155 9.7 65 45 165 10.4 66 45 175 10.8 67 45 185 10.8 68 45 195 11.7 69 45 205 12.6 70 45 215 14.0 71 45 225 14.3 72 45 235 14.9 77 45 285 11.2 78 45 295 12.7 79 45 305 14.4 80 45 315 15.9 81 45 325 16.3 82 45 335 17.0 83 45 345 16.2 84 45 355 15.5 85 35 5 15.4 86 35 15 15.0 87 35 25 15.2 88 35 35 14.1 89 35 45 18.4 90 35 55 9.9 96 35 115 4.7 97 35 125 13.6 98 35 135 13.0 99 35 145 11.4 100 35 155 14.1 101 35 165 14.2 102 35 175 14.0 103 35 185 14.7 104 35 195 15.4 105 35 205 16.8 106 35 215 18.2 107 35 225 17.2 108 35 235 13.6 109 35 245 10.3 112 35 275 16.3 113 35 285 18.6 114 35 295 19.5 115 35 305 19.0 116 35 315 19.1 117 35 325 18.1 118 35 335 18.9 119 35 345 15.7 120 35 355 14.4 124 25 35 6.3 125 25 45 13.0 126 25 55 7.8 127 25 65 4.5 128 25 75 2.3 129 25 85 6.0 130 25 95 5.4 131 25 105 24.6 132 25 115 17.3 133 25 125 17.4 134 25 135 14.9 135 25 145 15.1 136 25 155 14.3 137 25 165 13.1 138 25 175 12.7 139 25 185 12.6 140 25 195 12.1 141 25 205 12.7 142 25 215 16.7 143 25 225 18.9 144 25 235 18.3 145 25 245 13.7 146 25 255 15.2 147 25 265 19.8 148 25 275 15.8 149 25 285 14.0 150 25 295 12.3 151 25 305 12.0 152 25 315 13.0 153 25 325 13.4 154 25 335 11.5 155 25 345 9.0 156 25 355 8.4 160 15 35 9.0 161 15 45 6.4 162 15 55 5.5 163 15 65 5.1 164 15 75 5.1 165 15 85 7.8 166 15 95 7.4 167 15 105 14.5 168 15 115 13.4 169 15 125 13.3 170 15 135 13.9 171 15 145 11.7 172 15 155 9.5 173 15 165 8.1 174 15 175 9.4 175 15 185 10.5 176 15 195 11.7 177 15 205 12.9 178 15 215 16.9 179 15 225 19.7 180 15 235 22.1 181 15 245 18.3 182 15 255 11.2 183 15 265 6.8 184 15 275 11.3 185 15 285 9.2 186 15 295 9.7 187 15 305 10.6 188 15 315 12.9 189 15 325 15.1 190 15 335 14.7 191 15 345 11.7 193 5 5 17.4 197 5 45 8.1 198 5 55 9.8 199 5 65 10.0 200 5 75 12.9 201 5 85 20.2 202 5 95 24.4 203 5 105 22.8 204 5 115 23.5 205 5 125 21.4 206 5 135 26.8 207 5 145 20.3 208 5 155 20.7 209 5 165 22.9 210 5 175 22.7 211 5 185 19.1 212 5 195 18.8 213 5 205 18.8 214 5 215 17.6 215 5 225 18.4 216 5 235 20.7 217 5 245 20.1 218 5 255 16.6 219 5 265 16.9 220 5 275 18.6 221 5 285 18.9 222 5 295 14.4 223 5 305 17.4 224 5 315 22.7 225 5 325 23.7 226 5 335 21.2 227 5 345 14.6 228 5 355 16.3 229 -5 5 24.1 230 -5 15 20.9 232 -5 35 12.8 233 -5 45 12.5 234 -5 55 16.4 235 -5 65 21.9 236 -5 75 24.1 237 -5 85 25.8 238 -5 95 28.2 239 -5 105 35.4 240 -5 115 36.2 241 -5 125 29.2 242 -5 135 29.6 243 -5 145 31.8 244 -5 155 26.6 245 -5 165 29.3 246 -5 175 28.8 247 -5 185 21.2 248 -5 195 16.1 249 -5 205 12.1 250 -5 215 8.4 251 -5 225 6.7 252 -5 235 8.4 253 -5 245 11.9 254 -5 255 16.9 255 -5 265 17.8 256 -5 275 25.5 257 -5 285 18.9 260 -5 315 20.5 261 -5 325 13.8 262 -5 335 11.4 263 -5 345 13.1 264 -5 355 13.9 265 -15 5 20.2 266 -15 15 21.8 268 -15 35 16.3 269 -15 45 20.3 270 -15 55 16.9 271 -15 65 16.2 272 -15 75 17.6 273 -15 85 17.7 274 -15 95 19.9 275 -15 105 17.4 276 -15 115 14.0 277 -15 125 18.7 278 -15 135 24.8 279 -15 145 22.7 280 -15 155 17.4 281 -15 165 18.7 282 -15 175 23.5 283 -15 185 25.8 284 -15 195 26.4 285 -15 205 21.7 286 -15 215 15.6 287 -15 225 13.4 288 -15 235 13.7 289 -15 245 16.3 290 -15 255 18.0 291 -15 265 18.3 292 -15 275 19.4 293 -15 285 19.8 297 -15 325 16.2 298 -15 335 11.1 299 -15 345 14.5 300 -15 355 17.6 301 -25 5 14.6 302 -25 15 13.5 304 -25 35 13.9 305 -25 45 14.9 306 -25 55 17.0 307 -25 65 16.3 308 -25 75 16.9 309 -25 85 17.5 310 -25 95 20.1 311 -25 105 17.0 312 -25 115 10.1 315 -25 145 13.3 316 -25 155 15.4 317 -25 165 17.0 318 -25 175 20.4 319 -25 185 20.3 320 -25 195 23.4 321 -25 205 23.7 322 -25 215 21.1 323 -25 225 16.8 324 -25 235 17.1 325 -25 245 14.2 326 -25 255 15.4 327 -25 265 20.5 328 -25 275 17.0 329 -25 285 18.6 332 -25 315 23.8 333 -25 325 19.6 334 -25 335 15.9 335 -25 345 14.5 336 -25 355 16.7 337 -35 5 16.9 338 -35 15 9.9 339 -35 25 14.2 340 -35 35 16.5 341 -35 45 17.1 342 -35 55 16.4 343 -35 65 17.7 344 -35 75 17.9 345 -35 85 20.6 346 -35 95 21.2 347 -35 105 18.5 348 -35 115 13.2 349 -35 125 19.2 350 -35 135 18.4 351 -35 145 15.6 352 -35 155 16.1 353 -35 165 18.5 354 -35 175 18.4 355 -35 185 20.5 356 -35 195 20.6 357 -35 205 21.0 358 -35 215 19.5 359 -35 225 19.4 360 -35 235 17.5 361 -35 245 16.3 362 -35 255 18.3 363 -35 265 13.1 364 -35 275 12.4 365 -35 285 10.1 366 -35 295 15.2 367 -35 305 14.2 368 -35 315 16.4 369 -35 325 18.5 370 -35 335 19.6 371 -35 345 19.1 372 -35 355 18.9 373 -45 5 22.0 374 -45 15 21.3 375 -45 25 22.2 376 -45 35 23.3 377 -45 45 18.3 378 -45 55 18.7 379 -45 65 23.7 380 -45 75 24.7 381 -45 85 22.1 382 -45 95 20.2 383 -45 105 20.5 384 -45 115 20.7 385 -45 125 19.7 386 -45 135 22.9 387 -45 145 21.0 388 -45 155 19.2 389 -45 165 20.1 390 -45 175 19.4 391 -45 185 19.8 392 -45 195 20.7 393 -45 205 18.4 394 -45 215 18.0 395 -45 225 18.2 396 -45 235 15.9 397 -45 245 20.7 398 -45 255 19.9 399 -45 265 16.2 400 -45 275 12.3 401 -45 285 14.6 402 -45 295 13.4 403 -45 305 17.3 404 -45 315 19.0 405 -45 325 20.8 406 -45 335 19.4 407 -45 345 20.9 408 -45 355 20.2 409 -55 10 27.1 410 -55 30 25.4 411 -55 50 31.9 412 -55 70 25.0 413 -55 90 26.7 414 -55 110 22.4 415 -55 130 20.2 416 -55 150 17.2 417 -55 170 24.1 418 -55 190 23.6 419 -55 210 25.4 420 -55 230 21.1 421 -55 250 19.6 422 -55 270 17.2 423 -55 290 22.2 424 -55 310 27.2 425 -55 330 27.5 426 -55 350 27.8 427 -65 10 22.6 428 -65 30 26.1 429 -65 50 23.0 430 -65 70 20.3 431 -65 90 23.1 432 -65 110 16.3 433 -65 130 20.2 434 -65 150 21.4 435 -65 170 20.3 436 -65 190 23.4 437 -65 210 23.7 438 -65 230 17.9 439 -65 250 24.4 440 -65 270 24.7 441 -65 290 22.3 442 -65 310 36.4 443 -65 330 22.2 444 -65 350 21.0 449 -75 180 18.2 450 -75 220 16.2 451 -75 260 19.9 452 -75 300 23.9 453 -75 340 19.3