Altostratus Amount-When-Present (%) June, July, August (1954 - 1997) Day, Ship Observations Only Global Average: 56.7 Zonal Averages 15 zones Lat.N Average 85 83.4 75 68.3 65 71.7 55 71.8 45 67.8 35 55.8 25 46.9 15 56.3 5 60.0 -5 51.6 -15 47.9 -25 49.6 -35 56.7 -45 58.7 -55 65.4 Grid Box Averages 314 filled boxes Box # Lat.N Lon.E Average 1 85 60 80.3 2 85 180 88.3 4 75 20 66.5 5 75 60 57.3 6 75 100 60.8 7 75 140 71.2 8 75 180 81.9 9 75 220 77.3 10 75 260 77.2 11 75 300 66.2 12 75 340 73.6 13 65 10 64.4 14 65 30 56.0 15 65 50 52.6 21 65 170 67.0 22 65 190 73.4 23 65 210 67.0 25 65 250 76.7 26 65 270 76.1 27 65 290 78.2 28 65 310 76.4 29 65 330 83.0 30 65 350 66.5 31 55 10 72.5 32 55 30 55.5 37 55 130 53.5 38 55 150 64.9 39 55 170 74.3 40 55 190 74.3 41 55 210 67.7 42 55 230 64.7 45 55 290 78.6 46 55 310 73.5 47 55 330 77.3 48 55 350 72.6 49 45 5 45.6 50 45 15 46.8 51 45 25 43.1 52 45 35 42.2 53 45 45 21.5 54 45 55 28.7 62 45 135 67.2 63 45 145 65.2 64 45 155 67.6 65 45 165 71.3 66 45 175 72.1 67 45 185 72.5 68 45 195 71.8 69 45 205 68.6 70 45 215 65.0 71 45 225 62.3 72 45 235 53.7 77 45 285 60.8 78 45 295 66.2 79 45 305 68.0 80 45 315 69.8 81 45 325 67.8 82 45 335 68.3 83 45 345 68.3 84 45 355 61.1 85 35 5 52.7 86 35 15 44.4 87 35 25 38.2 88 35 35 31.8 96 35 115 62.0 97 35 125 63.9 98 35 135 60.3 99 35 145 56.5 100 35 155 57.5 101 35 165 63.4 102 35 175 56.3 103 35 185 59.2 104 35 195 56.0 105 35 205 50.1 106 35 215 49.9 107 35 225 52.0 108 35 235 54.3 109 35 245 57.4 112 35 275 46.2 113 35 285 60.0 114 35 295 62.5 115 35 305 54.8 116 35 315 49.7 117 35 325 47.8 118 35 335 48.4 119 35 345 53.6 120 35 355 50.7 124 25 35 47.7 126 25 55 62.4 127 25 65 63.3 129 25 85 69.6 132 25 115 57.0 133 25 125 48.8 134 25 135 45.8 135 25 145 44.2 136 25 155 47.3 137 25 165 42.2 138 25 175 41.8 139 25 185 39.1 140 25 195 35.4 141 25 205 32.7 142 25 215 41.1 143 25 225 50.8 144 25 235 54.8 145 25 245 43.5 146 25 255 40.7 147 25 265 46.7 148 25 275 46.3 149 25 285 45.4 150 25 295 48.2 151 25 305 45.0 152 25 315 38.9 153 25 325 40.8 154 25 335 56.2 155 25 345 63.6 160 15 35 64.6 161 15 45 67.4 162 15 55 60.1 163 15 65 64.4 164 15 75 71.3 165 15 85 67.3 166 15 95 72.2 167 15 105 66.7 168 15 115 59.6 169 15 125 54.7 170 15 135 59.3 171 15 145 49.6 172 15 155 52.4 173 15 165 50.8 174 15 175 46.5 175 15 185 43.1 176 15 195 43.3 177 15 205 41.7 178 15 215 44.6 179 15 225 45.2 180 15 235 49.5 181 15 245 52.1 182 15 255 55.9 183 15 265 62.0 184 15 275 57.5 185 15 285 50.4 186 15 295 47.7 187 15 305 50.4 188 15 315 53.5 189 15 325 56.5 190 15 335 64.9 191 15 345 70.5 193 5 5 69.4 197 5 45 41.4 198 5 55 46.7 199 5 65 62.7 200 5 75 69.0 201 5 85 66.1 202 5 95 72.9 203 5 105 65.5 204 5 115 65.5 205 5 125 59.9 206 5 135 63.3 207 5 145 53.4 208 5 155 53.6 209 5 165 52.9 210 5 175 60.5 211 5 185 48.2 212 5 195 57.9 213 5 205 53.5 214 5 215 52.0 215 5 225 47.4 216 5 235 48.7 217 5 245 57.9 218 5 255 63.3 219 5 265 65.3 220 5 275 72.9 221 5 285 78.2 223 5 305 49.5 224 5 315 44.3 225 5 325 46.2 226 5 335 62.0 227 5 345 71.4 228 5 355 65.7 229 -5 5 56.3 230 -5 15 66.3 233 -5 45 40.6 234 -5 55 45.1 235 -5 65 63.0 236 -5 75 60.5 237 -5 85 72.4 238 -5 95 64.6 239 -5 105 49.1 240 -5 115 37.8 241 -5 125 41.3 242 -5 135 51.5 243 -5 145 55.7 244 -5 155 54.1 245 -5 165 52.5 246 -5 175 49.8 247 -5 185 52.6 248 -5 195 38.4 252 -5 235 24.9 253 -5 245 28.2 254 -5 255 37.8 255 -5 265 43.4 256 -5 275 63.4 257 -5 285 83.9 260 -5 315 30.9 261 -5 325 38.6 262 -5 335 29.6 263 -5 345 35.7 264 -5 355 47.7 265 -15 5 57.9 266 -15 15 70.9 268 -15 35 31.8 269 -15 45 31.8 270 -15 55 43.4 271 -15 65 43.6 272 -15 75 46.2 273 -15 85 55.0 274 -15 95 55.6 275 -15 105 40.8 276 -15 115 33.3 277 -15 125 30.0 278 -15 135 37.5 279 -15 145 41.6 280 -15 155 44.3 281 -15 165 51.0 282 -15 175 47.7 283 -15 185 50.9 284 -15 195 43.4 285 -15 205 43.9 286 -15 215 40.0 287 -15 225 37.1 288 -15 235 44.6 289 -15 245 41.1 290 -15 255 35.9 292 -15 275 65.0 293 -15 285 75.0 297 -15 325 38.3 298 -15 335 32.8 299 -15 345 36.2 300 -15 355 53.3 301 -25 5 45.0 302 -25 15 54.1 304 -25 35 41.7 305 -25 45 38.2 306 -25 55 40.9 307 -25 65 41.7 308 -25 75 44.3 309 -25 85 45.6 310 -25 95 48.3 311 -25 105 55.2 312 -25 115 44.3 316 -25 155 47.3 317 -25 165 47.6 318 -25 175 57.1 319 -25 185 59.4 320 -25 195 64.2 321 -25 205 61.8 322 -25 215 62.0 323 -25 225 57.0 324 -25 235 55.8 328 -25 275 38.5 329 -25 285 62.8 332 -25 315 49.7 333 -25 325 37.6 334 -25 335 46.4 335 -25 345 39.4 336 -25 355 43.5 337 -35 5 51.7 338 -35 15 52.0 339 -35 25 50.9 340 -35 35 47.6 341 -35 45 46.1 342 -35 55 48.6 343 -35 65 51.6 344 -35 75 50.0 345 -35 85 57.0 346 -35 95 53.3 347 -35 105 54.0 348 -35 115 54.6 349 -35 125 53.5 350 -35 135 56.1 351 -35 145 53.8 352 -35 155 54.5 353 -35 165 58.4 354 -35 175 61.4 355 -35 185 62.0 356 -35 195 63.3 357 -35 205 68.0 358 -35 215 71.5 359 -35 225 71.2 364 -35 275 46.8 365 -35 285 56.3 367 -35 305 53.8 368 -35 315 62.8 369 -35 325 58.6 370 -35 335 61.9 371 -35 345 61.5 372 -35 355 53.2 387 -45 145 52.7 388 -45 155 62.2 389 -45 165 64.3 390 -45 175 57.7 392 -45 195 60.9 393 -45 205 68.8 398 -45 255 43.3 400 -45 275 53.4 401 -45 285 58.3 402 -45 295 55.3 403 -45 305 55.0 404 -45 315 66.9 405 -45 325 62.4 417 -55 170 80.2 423 -55 290 65.6 424 -55 310 63.6 425 -55 330 57.8