Altocumulus Average Cloud Amount (%) December, January, February (1954 - 1997) Night, Ship Observations Only Global Average: 17.3 Zonal Averages 17 zones Lat.N Average 85 12.0 75 11.3 65 11.5 55 10.8 45 11.9 35 14.8 25 13.5 15 11.8 5 19.1 -5 20.0 -15 18.5 -25 18.0 -35 17.1 -45 19.8 -55 23.9 -65 22.5 -75 20.1 Grid Box Averages 378 filled boxes Box # Lat.N Lon.E Average 1 85 60 14.1 2 85 180 9.1 3 85 300 13.5 4 75 20 12.5 5 75 60 8.1 7 75 140 8.1 8 75 180 11.6 9 75 220 15.2 12 75 340 11.6 13 65 10 15.5 14 65 30 13.1 15 65 50 9.2 21 65 170 4.0 22 65 190 4.2 23 65 210 6.0 29 65 330 12.2 30 65 350 14.9 31 55 10 12.1 32 55 30 18.7 38 55 150 7.0 39 55 170 9.3 40 55 190 9.3 41 55 210 10.5 42 55 230 10.2 46 55 310 10.0 47 55 330 14.5 48 55 350 13.1 49 45 5 14.3 50 45 15 14.8 51 45 25 12.1 52 45 35 10.7 53 45 45 12.2 54 45 55 8.7 62 45 135 6.3 63 45 145 7.7 64 45 155 9.5 65 45 165 9.9 66 45 175 10.1 67 45 185 9.9 68 45 195 11.2 69 45 205 11.9 70 45 215 12.9 71 45 225 12.2 72 45 235 12.5 77 45 285 9.8 78 45 295 11.6 79 45 305 12.6 80 45 315 14.0 81 45 325 14.6 82 45 335 15.0 83 45 345 14.4 84 45 355 13.7 85 35 5 14.1 86 35 15 13.4 87 35 25 13.7 88 35 35 12.9 96 35 115 2.9 97 35 125 12.4 98 35 135 12.1 99 35 145 10.3 100 35 155 13.3 101 35 165 13.4 102 35 175 13.3 103 35 185 14.1 104 35 195 14.6 105 35 205 15.3 106 35 215 17.1 107 35 225 15.6 108 35 235 12.2 109 35 245 9.7 112 35 275 16.0 113 35 285 17.1 114 35 295 17.9 115 35 305 17.7 116 35 315 17.6 117 35 325 16.4 118 35 335 17.6 119 35 345 14.9 120 35 355 13.2 124 25 35 6.0 125 25 45 11.7 126 25 55 7.3 127 25 65 4.4 128 25 75 1.4 129 25 85 7.0 130 25 95 3.9 132 25 115 15.8 133 25 125 16.9 134 25 135 15.1 135 25 145 15.2 136 25 155 13.9 137 25 165 12.8 138 25 175 12.9 139 25 185 12.9 140 25 195 11.5 141 25 205 11.6 142 25 215 16.3 143 25 225 18.9 144 25 235 18.4 145 25 245 12.9 146 25 255 14.0 147 25 265 19.0 148 25 275 15.6 149 25 285 13.6 150 25 295 11.6 151 25 305 11.2 152 25 315 12.2 153 25 325 12.8 154 25 335 10.8 155 25 345 8.8 160 15 35 8.1 161 15 45 6.2 162 15 55 5.4 163 15 65 5.1 164 15 75 4.9 165 15 85 8.0 166 15 95 7.3 167 15 105 13.5 168 15 115 12.8 169 15 125 12.3 170 15 135 14.0 171 15 145 12.1 172 15 155 9.0 173 15 165 7.6 174 15 175 9.1 175 15 185 10.8 176 15 195 11.6 177 15 205 12.5 178 15 215 17.4 179 15 225 19.8 180 15 235 22.1 181 15 245 17.9 182 15 255 10.9 183 15 265 7.4 184 15 275 12.1 185 15 285 8.7 186 15 295 9.0 187 15 305 10.1 188 15 315 12.8 189 15 325 15.3 190 15 335 15.6 191 15 345 12.2 193 5 5 18.2 197 5 45 8.8 198 5 55 10.4 199 5 65 9.4 200 5 75 12.5 201 5 85 19.3 202 5 95 24.5 203 5 105 21.1 204 5 115 22.0 205 5 125 20.1 206 5 135 27.4 207 5 145 18.9 208 5 155 19.5 209 5 165 22.1 210 5 175 23.1 211 5 185 20.4 212 5 195 18.4 213 5 205 18.6 214 5 215 15.9 215 5 225 18.9 216 5 235 22.0 217 5 245 22.3 218 5 255 17.1 219 5 265 17.1 220 5 275 20.2 221 5 285 18.8 223 5 305 17.2 224 5 315 22.1 225 5 325 24.2 226 5 335 21.4 227 5 345 14.3 228 5 355 16.4 229 -5 5 27.6 230 -5 15 19.1 232 -5 35 13.6 233 -5 45 11.8 234 -5 55 16.1 235 -5 65 23.2 236 -5 75 23.0 237 -5 85 25.0 238 -5 95 28.6 239 -5 105 35.0 240 -5 115 33.7 241 -5 125 26.2 242 -5 135 27.3 243 -5 145 29.7 244 -5 155 24.1 245 -5 165 28.2 246 -5 175 26.6 247 -5 185 21.5 248 -5 195 16.8 249 -5 205 12.6 250 -5 215 8.8 251 -5 225 6.1 252 -5 235 8.0 253 -5 245 12.6 254 -5 255 18.8 255 -5 265 19.8 256 -5 275 31.5 257 -5 285 19.0 260 -5 315 19.6 261 -5 325 13.4 262 -5 335 11.4 263 -5 345 14.9 264 -5 355 15.9 265 -15 5 23.7 266 -15 15 20.4 268 -15 35 16.4 269 -15 45 18.2 270 -15 55 17.7 271 -15 65 16.4 272 -15 75 16.9 273 -15 85 18.1 274 -15 95 21.7 275 -15 105 17.6 276 -15 115 14.5 277 -15 125 16.3 278 -15 135 22.9 279 -15 145 22.6 280 -15 155 16.7 281 -15 165 17.4 282 -15 175 23.3 283 -15 185 25.3 284 -15 195 27.7 285 -15 205 21.0 286 -15 215 12.6 287 -15 225 12.4 288 -15 235 13.7 289 -15 245 16.8 290 -15 255 19.4 291 -15 265 20.1 292 -15 275 23.2 293 -15 285 19.9 297 -15 325 15.7 298 -15 335 11.1 299 -15 345 15.6 300 -15 355 19.2 301 -25 5 17.5 302 -25 15 12.0 304 -25 35 13.6 305 -25 45 14.9 306 -25 55 17.2 307 -25 65 16.0 308 -25 75 18.2 309 -25 85 19.9 310 -25 95 22.9 311 -25 105 16.6 312 -25 115 10.1 315 -25 145 11.1 316 -25 155 15.4 317 -25 165 17.1 318 -25 175 21.4 319 -25 185 21.2 320 -25 195 24.2 321 -25 205 23.3 322 -25 215 19.5 323 -25 225 13.7 324 -25 235 15.8 325 -25 245 13.4 326 -25 255 15.2 327 -25 265 24.9 328 -25 275 19.2 329 -25 285 17.3 332 -25 315 23.6 333 -25 325 18.0 334 -25 335 15.0 335 -25 345 15.7 336 -25 355 17.5 337 -35 5 18.1 338 -35 15 9.5 339 -35 25 14.3 340 -35 35 16.1 341 -35 45 17.4 342 -35 55 15.8 343 -35 65 17.6 344 -35 75 18.1 345 -35 85 21.4 346 -35 95 22.7 347 -35 105 17.2 348 -35 115 12.6 349 -35 125 19.2 350 -35 135 18.6 351 -35 145 14.2 352 -35 155 16.0 353 -35 165 18.7 354 -35 175 18.0 355 -35 185 21.0 356 -35 195 20.1 357 -35 205 20.5 358 -35 215 17.1 359 -35 225 17.5 360 -35 235 14.9 361 -35 245 14.3 362 -35 255 18.2 363 -35 265 14.6 364 -35 275 12.7 365 -35 285 9.5 367 -35 305 14.5 368 -35 315 15.9 369 -35 325 17.1 370 -35 335 18.2 371 -35 345 19.6 372 -35 355 19.1 373 -45 5 19.3 374 -45 15 20.4 375 -45 25 22.1 376 -45 35 23.4 377 -45 45 16.3 378 -45 55 18.2 379 -45 65 25.4 380 -45 75 24.3 381 -45 85 21.1 382 -45 95 22.1 383 -45 105 21.9 384 -45 115 21.1 385 -45 125 18.2 386 -45 135 23.3 387 -45 145 19.6 388 -45 155 18.9 389 -45 165 21.3 390 -45 175 19.3 391 -45 185 20.3 392 -45 195 19.9 393 -45 205 19.0 394 -45 215 16.6 399 -45 265 17.8 400 -45 275 13.4 401 -45 285 13.8 402 -45 295 13.0 403 -45 305 17.5 404 -45 315 17.6 405 -45 325 20.5 406 -45 335 21.2 407 -45 345 20.1 408 -45 355 19.6 409 -55 10 25.4 410 -55 30 25.9 411 -55 50 30.1 412 -55 70 25.6 413 -55 90 27.2 414 -55 110 22.8 415 -55 130 19.3 416 -55 150 16.5 417 -55 170 25.2 418 -55 190 24.5 419 -55 210 28.4 420 -55 230 21.6 421 -55 250 19.1 422 -55 270 17.8 423 -55 290 21.3 424 -55 310 27.3 425 -55 330 27.4 426 -55 350 24.9 427 -65 10 22.1 428 -65 30 26.1 429 -65 50 23.1 430 -65 70 20.3 431 -65 90 23.1 432 -65 110 15.4 433 -65 130 19.8 434 -65 150 20.9 435 -65 170 20.2 436 -65 190 23.7 437 -65 210 24.3 438 -65 230 18.6 439 -65 250 22.6 440 -65 270 22.6 441 -65 290 22.1 442 -65 310 37.3 443 -65 330 18.4 444 -65 350 20.4 449 -75 180 19.1 450 -75 220 19.2 451 -75 260 22.0 452 -75 300 22.1 453 -75 340 19.6