Altocumulus Average Cloud Amount (%) August (1954 - 1997) Night, Ship Observations Only Global Average: 16.7 Zonal Averages 15 zones Lat.N Average 85 18.7 75 18.5 65 20.9 55 17.9 45 18.3 35 13.8 25 13.3 15 17.8 5 23.6 -5 16.7 -15 15.8 -25 15.8 -35 14.4 -45 12.8 -55 17.9 Grid Box Averages 314 filled boxes Box # Lat.N Lon.E Average 1 85 60 23.8 2 85 180 14.4 3 85 300 18.0 4 75 20 22.0 5 75 60 19.3 6 75 100 17.2 7 75 140 17.3 8 75 180 14.6 9 75 220 16.8 10 75 260 21.7 11 75 300 19.8 12 75 340 21.2 13 65 10 22.9 14 65 30 16.9 15 65 50 15.4 21 65 170 12.3 22 65 190 19.8 23 65 210 19.9 24 65 230 22.6 25 65 250 23.8 26 65 270 23.2 27 65 290 21.0 28 65 310 20.8 29 65 330 20.2 30 65 350 23.1 31 55 10 20.2 32 55 30 16.3 38 55 150 13.7 39 55 170 13.2 40 55 190 16.9 41 55 210 19.1 42 55 230 18.3 44 55 270 19.5 45 55 290 24.3 46 55 310 17.6 47 55 330 20.5 48 55 350 21.7 49 45 5 10.4 50 45 15 7.0 51 45 25 5.6 52 45 35 6.0 62 45 135 16.3 63 45 145 14.5 64 45 155 17.7 65 45 165 17.4 66 45 175 20.5 67 45 185 24.6 68 45 195 22.4 69 45 205 23.3 70 45 215 23.8 71 45 225 18.8 72 45 235 12.1 77 45 285 14.8 78 45 295 15.9 79 45 305 17.3 80 45 315 16.0 81 45 325 17.6 82 45 335 18.9 83 45 345 17.4 84 45 355 17.4 85 35 5 8.2 86 35 15 3.8 87 35 25 1.2 88 35 35 1.4 97 35 125 16.0 98 35 135 16.2 99 35 145 18.6 100 35 155 16.7 101 35 165 15.9 102 35 175 16.4 103 35 185 17.4 104 35 195 15.9 105 35 205 17.4 106 35 215 17.9 107 35 225 16.2 108 35 235 11.7 109 35 245 6.8 112 35 275 13.9 113 35 285 17.7 114 35 295 15.4 115 35 305 11.2 116 35 315 10.9 117 35 325 10.8 118 35 335 13.1 119 35 345 10.1 120 35 355 7.7 124 25 35 5.8 125 25 45 1.9 126 25 55 8.8 127 25 65 22.9 129 25 85 25.2 132 25 115 16.1 133 25 125 14.2 134 25 135 14.8 135 25 145 16.3 136 25 155 14.9 137 25 165 12.4 138 25 175 13.9 139 25 185 11.9 140 25 195 12.2 141 25 205 12.4 142 25 215 15.8 143 25 225 21.1 144 25 235 17.6 145 25 245 12.6 146 25 255 17.0 147 25 265 14.7 148 25 275 14.5 149 25 285 13.6 150 25 295 9.6 151 25 305 7.1 152 25 315 8.5 153 25 325 10.5 154 25 335 10.4 155 25 345 9.8 160 15 35 22.3 161 15 45 20.7 162 15 55 11.3 163 15 65 21.1 164 15 75 26.3 165 15 85 23.9 166 15 95 32.0 167 15 105 29.7 168 15 115 19.8 169 15 125 18.8 170 15 135 21.1 171 15 145 20.3 172 15 155 16.9 173 15 165 10.0 174 15 175 13.1 175 15 185 13.8 176 15 195 11.0 177 15 205 16.1 178 15 215 18.3 179 15 225 19.6 180 15 235 19.1 181 15 245 17.0 182 15 255 25.4 183 15 265 27.9 184 15 275 21.4 185 15 285 14.4 186 15 295 10.3 187 15 305 10.6 188 15 315 13.8 189 15 325 16.2 190 15 335 19.2 191 15 345 21.0 193 5 5 34.7 197 5 45 9.9 198 5 55 7.6 199 5 65 12.2 200 5 75 21.2 201 5 85 25.3 202 5 95 37.0 203 5 105 27.1 204 5 115 24.2 205 5 125 27.2 206 5 135 29.4 207 5 145 22.1 208 5 155 21.3 209 5 165 19.6 210 5 175 17.3 211 5 185 21.5 212 5 195 18.1 213 5 205 19.8 214 5 215 22.0 215 5 225 21.9 216 5 235 24.7 217 5 245 29.6 218 5 255 25.6 219 5 265 31.4 220 5 275 37.6 221 5 285 35.0 223 5 305 18.5 224 5 315 20.6 225 5 325 19.6 226 5 335 25.9 227 5 345 29.2 228 5 355 26.8 229 -5 5 28.2 230 -5 15 23.0 233 -5 45 10.4 234 -5 55 14.4 235 -5 65 20.7 236 -5 75 20.6 237 -5 85 28.2 238 -5 95 25.9 239 -5 105 21.6 240 -5 115 12.5 241 -5 125 15.6 242 -5 135 20.7 243 -5 145 26.2 244 -5 155 22.9 245 -5 165 26.0 246 -5 175 12.7 247 -5 185 12.7 248 -5 195 9.1 249 -5 205 10.3 250 -5 215 7.6 251 -5 225 7.1 252 -5 235 10.3 253 -5 245 12.0 254 -5 255 19.3 255 -5 265 24.5 256 -5 275 18.9 260 -5 315 12.1 261 -5 325 10.1 262 -5 335 11.9 263 -5 345 12.8 264 -5 355 15.9 265 -15 5 24.7 266 -15 15 42.1 268 -15 35 5.8 269 -15 45 9.5 270 -15 55 17.6 271 -15 65 15.8 272 -15 75 19.2 273 -15 85 17.6 274 -15 95 20.9 275 -15 105 13.9 276 -15 115 6.0 277 -15 125 3.1 278 -15 135 10.2 279 -15 145 12.3 280 -15 155 16.5 281 -15 165 17.9 282 -15 175 17.3 283 -15 185 18.6 284 -15 195 14.0 285 -15 205 18.4 286 -15 215 12.1 287 -15 225 11.1 288 -15 235 9.3 289 -15 245 11.5 290 -15 255 16.4 292 -15 275 12.1 293 -15 285 18.0 297 -15 325 12.6 298 -15 335 17.1 299 -15 345 21.9 300 -15 355 25.1 301 -25 5 14.3 302 -25 15 12.5 304 -25 35 6.6 305 -25 45 9.3 306 -25 55 14.3 307 -25 65 16.9 308 -25 75 19.3 309 -25 85 20.1 310 -25 95 17.8 311 -25 105 19.0 312 -25 115 8.6 316 -25 155 10.3 317 -25 165 14.4 318 -25 175 16.9 319 -25 185 16.6 320 -25 195 19.3 321 -25 205 21.6 322 -25 215 14.6 323 -25 225 15.4 324 -25 235 15.7 325 -25 245 13.8 328 -25 275 7.9 329 -25 285 16.8 332 -25 315 17.8 333 -25 325 16.4 334 -25 335 16.0 335 -25 345 20.3 336 -25 355 19.5 337 -35 5 19.9 338 -35 15 10.0 339 -35 25 10.1 340 -35 35 9.6 341 -35 45 15.6 342 -35 55 16.0 343 -35 65 16.6 344 -35 75 18.1 345 -35 85 13.2 346 -35 95 13.3 347 -35 105 13.1 348 -35 115 13.5 349 -35 125 15.3 350 -35 135 15.7 351 -35 145 14.3 352 -35 155 13.3 353 -35 165 12.2 354 -35 175 12.7 355 -35 185 14.8 356 -35 195 12.8 357 -35 205 14.0 358 -35 215 14.8 359 -35 225 18.6 364 -35 275 6.5 365 -35 285 14.9 367 -35 305 13.9 368 -35 315 17.6 369 -35 325 17.1 370 -35 335 13.7 371 -35 345 15.1 372 -35 355 17.8 387 -45 145 17.4 388 -45 155 16.4 389 -45 165 15.2 390 -45 175 15.1 391 -45 185 6.9 400 -45 275 6.7 401 -45 285 15.3 402 -45 295 15.0 403 -45 305 14.6 404 -45 315 8.7 417 -55 170 20.4 423 -55 290 11.8 424 -55 310 26.5 425 -55 330 12.0