Altocumulus Frequency of Occurrence (%) August (1954 - 1997) Night, Ship Observations Only Global Average: 34.1 Zonal Averages 15 zones Lat.N Average 85 30.0 75 34.0 65 39.9 55 35.4 45 36.5 35 33.0 25 33.7 15 38.7 5 44.7 -5 34.4 -15 32.8 -25 34.0 -35 30.6 -45 26.2 -55 28.7 Grid Box Averages 314 filled boxes Box # Lat.N Lon.E Average 1 85 60 37.0 2 85 180 22.5 3 85 300 31.1 4 75 20 41.2 5 75 60 36.9 6 75 100 31.4 7 75 140 33.9 8 75 180 24.3 9 75 220 28.7 10 75 260 42.9 11 75 300 39.9 12 75 340 37.4 13 65 10 44.5 14 65 30 35.5 15 65 50 31.7 21 65 170 24.9 22 65 190 33.7 23 65 210 41.3 24 65 230 44.7 25 65 250 47.2 26 65 270 46.1 27 65 290 42.5 28 65 310 39.5 29 65 330 37.8 30 65 350 43.5 31 55 10 40.1 32 55 30 34.1 38 55 150 25.6 39 55 170 26.6 40 55 190 31.9 41 55 210 37.7 42 55 230 38.9 44 55 270 48.1 45 55 290 52.4 46 55 310 36.4 47 55 330 36.4 48 55 350 43.6 49 45 5 26.5 50 45 15 20.9 51 45 25 13.5 52 45 35 13.7 62 45 135 30.1 63 45 145 28.7 64 45 155 38.2 65 45 165 35.5 66 45 175 37.6 67 45 185 42.2 68 45 195 43.3 69 45 205 46.6 70 45 215 44.6 71 45 225 39.3 72 45 235 29.4 77 45 285 32.8 78 45 295 33.8 79 45 305 35.3 80 45 315 31.7 81 45 325 35.4 82 45 335 38.0 83 45 345 36.1 84 45 355 38.5 85 35 5 21.6 86 35 15 11.9 87 35 25 3.8 88 35 35 4.6 97 35 125 33.4 98 35 135 38.0 99 35 145 44.1 100 35 155 40.4 101 35 165 35.5 102 35 175 39.9 103 35 185 40.0 104 35 195 43.5 105 35 205 43.8 106 35 215 41.3 107 35 225 34.8 108 35 235 25.8 109 35 245 15.0 112 35 275 37.9 113 35 285 37.7 114 35 295 33.7 115 35 305 28.8 116 35 315 29.5 117 35 325 28.0 118 35 335 31.2 119 35 345 24.6 120 35 355 20.6 124 25 35 12.9 125 25 45 6.5 126 25 55 17.9 127 25 65 35.0 129 25 85 47.5 132 25 115 33.5 133 25 125 35.2 134 25 135 40.2 135 25 145 43.3 136 25 155 38.9 137 25 165 36.7 138 25 175 39.2 139 25 185 36.4 140 25 195 37.7 141 25 205 33.8 142 25 215 38.2 143 25 225 37.4 144 25 235 33.7 145 25 245 30.9 146 25 255 41.5 147 25 265 39.1 148 25 275 40.9 149 25 285 37.9 150 25 295 27.6 151 25 305 22.3 152 25 315 25.3 153 25 325 27.3 154 25 335 22.7 155 25 345 20.3 160 15 35 40.5 161 15 45 35.6 162 15 55 20.9 163 15 65 36.2 164 15 75 42.4 165 15 85 43.6 166 15 95 49.0 167 15 105 51.6 168 15 115 40.0 169 15 125 42.3 170 15 135 48.3 171 15 145 48.9 172 15 155 36.9 173 15 165 34.8 174 15 175 34.5 175 15 185 36.7 176 15 195 32.2 177 15 205 39.6 178 15 215 39.9 179 15 225 42.8 180 15 235 41.4 181 15 245 40.0 182 15 255 49.9 183 15 265 52.4 184 15 275 46.0 185 15 285 35.4 186 15 295 28.1 187 15 305 26.4 188 15 315 33.5 189 15 325 33.1 190 15 335 35.9 191 15 345 36.0 193 5 5 52.9 197 5 45 23.4 198 5 55 17.5 199 5 65 27.8 200 5 75 39.0 201 5 85 46.0 202 5 95 57.3 203 5 105 47.8 204 5 115 44.3 205 5 125 48.7 206 5 135 54.7 207 5 145 51.9 208 5 155 49.4 209 5 165 42.1 210 5 175 47.0 211 5 185 47.7 212 5 195 38.8 213 5 205 41.8 214 5 215 39.0 215 5 225 43.4 216 5 235 52.4 217 5 245 50.8 218 5 255 43.7 219 5 265 53.7 220 5 275 62.0 221 5 285 55.2 223 5 305 41.1 224 5 315 40.6 225 5 325 35.9 226 5 335 44.3 227 5 345 44.7 228 5 355 42.2 229 -5 5 37.8 230 -5 15 26.2 233 -5 45 26.2 234 -5 55 29.7 235 -5 65 37.8 236 -5 75 41.9 237 -5 85 50.6 238 -5 95 52.0 239 -5 105 40.4 240 -5 115 27.3 241 -5 125 30.6 242 -5 135 35.3 243 -5 145 47.5 244 -5 155 47.4 245 -5 165 42.4 246 -5 175 41.1 247 -5 185 38.6 248 -5 195 28.0 249 -5 205 31.7 250 -5 215 26.2 251 -5 225 23.5 252 -5 235 23.8 253 -5 245 27.9 254 -5 255 37.1 255 -5 265 44.1 256 -5 275 30.6 260 -5 315 26.9 261 -5 325 25.6 262 -5 335 25.3 263 -5 345 24.3 264 -5 355 27.8 265 -15 5 36.6 266 -15 15 46.1 268 -15 35 15.1 269 -15 45 21.4 270 -15 55 38.8 271 -15 65 34.4 272 -15 75 40.4 273 -15 85 40.8 274 -15 95 45.8 275 -15 105 30.7 276 -15 115 13.6 277 -15 125 7.7 278 -15 135 18.9 279 -15 145 24.4 280 -15 155 35.8 281 -15 165 37.1 282 -15 175 40.9 283 -15 185 44.9 284 -15 195 33.0 285 -15 205 37.5 286 -15 215 29.9 287 -15 225 26.4 288 -15 235 24.3 289 -15 245 27.4 290 -15 255 35.1 292 -15 275 21.2 293 -15 285 30.7 297 -15 325 30.6 298 -15 335 32.8 299 -15 345 40.3 300 -15 355 40.3 301 -25 5 28.6 302 -25 15 21.3 304 -25 35 15.8 305 -25 45 25.4 306 -25 55 31.7 307 -25 65 35.4 308 -25 75 41.2 309 -25 85 44.6 310 -25 95 40.6 311 -25 105 38.7 312 -25 115 20.6 316 -25 155 23.5 317 -25 165 33.4 318 -25 175 37.8 319 -25 185 39.1 320 -25 195 39.8 321 -25 205 40.4 322 -25 215 28.4 323 -25 225 32.4 324 -25 235 32.3 325 -25 245 32.5 328 -25 275 26.8 329 -25 285 26.0 332 -25 315 33.7 333 -25 325 35.4 334 -25 335 33.0 335 -25 345 46.7 336 -25 355 40.2 337 -35 5 39.1 338 -35 15 22.4 339 -35 25 22.6 340 -35 35 21.0 341 -35 45 35.7 342 -35 55 33.8 343 -35 65 36.0 344 -35 75 38.6 345 -35 85 26.2 346 -35 95 31.7 347 -35 105 30.6 348 -35 115 31.3 349 -35 125 33.0 350 -35 135 31.4 351 -35 145 32.7 352 -35 155 29.7 353 -35 165 27.8 354 -35 175 29.1 355 -35 185 35.3 356 -35 195 28.9 357 -35 205 24.6 358 -35 215 33.8 359 -35 225 37.7 364 -35 275 19.2 365 -35 285 27.3 367 -35 305 26.9 368 -35 315 31.7 369 -35 325 32.3 370 -35 335 26.6 371 -35 345 33.4 372 -35 355 33.7 387 -45 145 39.5 388 -45 155 30.5 389 -45 165 27.3 390 -45 175 30.5 391 -45 185 14.7 400 -45 275 20.9 401 -45 285 29.1 402 -45 295 31.9 403 -45 305 26.3 404 -45 315 16.8 417 -55 170 27.3 423 -55 290 25.6 424 -55 310 35.6 425 -55 330 25.8