Altostratus Amount-When-Present (%) June, July, August (1954 - 1997) Night, Ship Observations Only Global Average: 60.2 Zonal Averages 15 zones Lat.N Average 85 75.2 75 66.2 65 68.3 55 70.9 45 69.5 35 58.8 25 48.3 15 57.3 5 64.0 -5 60.5 -15 59.0 -25 58.3 -35 60.5 -45 61.7 -55 57.1 Grid Box Averages 244 filled boxes Box # Lat.N Lon.E Average 1 85 60 72.2 2 85 180 80.2 4 75 20 65.3 5 75 60 59.6 6 75 100 63.5 8 75 180 81.4 9 75 220 67.8 10 75 260 69.6 11 75 300 60.1 12 75 340 65.2 13 65 10 65.2 14 65 30 54.4 15 65 50 54.1 21 65 170 66.3 22 65 190 67.8 23 65 210 48.0 25 65 250 60.0 26 65 270 66.5 27 65 290 66.6 28 65 310 70.7 29 65 330 77.2 30 65 350 68.3 31 55 10 68.9 32 55 30 48.4 38 55 150 58.7 39 55 170 73.4 40 55 190 75.8 41 55 210 68.9 42 55 230 65.7 45 55 290 57.2 46 55 310 72.4 47 55 330 78.0 48 55 350 73.8 49 45 5 45.9 50 45 15 41.6 52 45 35 41.6 62 45 135 58.6 63 45 145 63.5 64 45 155 68.0 65 45 165 74.6 66 45 175 76.8 67 45 185 78.0 68 45 195 72.7 69 45 205 70.1 70 45 215 69.3 71 45 225 68.0 72 45 235 53.4 77 45 285 57.9 78 45 295 59.4 79 45 305 64.5 80 45 315 71.1 81 45 325 72.5 82 45 335 73.4 83 45 345 70.1 84 45 355 63.1 85 35 5 51.2 86 35 15 39.7 87 35 25 34.0 88 35 35 31.8 97 35 125 63.0 98 35 135 62.3 99 35 145 58.6 100 35 155 61.8 101 35 165 68.4 102 35 175 60.8 103 35 185 59.9 104 35 195 58.2 105 35 205 53.5 106 35 215 58.9 107 35 225 60.5 108 35 235 60.0 109 35 245 62.3 112 35 275 43.1 113 35 285 56.5 114 35 295 60.7 115 35 305 56.9 116 35 315 58.9 117 35 325 52.0 118 35 335 54.5 119 35 345 57.2 120 35 355 48.4 124 25 35 49.1 126 25 55 61.1 127 25 65 64.2 132 25 115 57.1 133 25 125 46.1 134 25 135 45.3 135 25 145 43.6 136 25 155 46.4 137 25 165 39.9 138 25 175 41.8 139 25 185 42.8 140 25 195 35.4 141 25 205 37.1 142 25 215 53.4 143 25 225 56.7 144 25 235 69.1 145 25 245 50.1 146 25 255 50.5 147 25 265 41.5 148 25 275 42.0 149 25 285 48.4 150 25 295 47.9 151 25 305 46.9 152 25 315 38.6 153 25 325 39.3 154 25 335 52.7 155 25 345 58.9 160 15 35 59.4 161 15 45 65.8 162 15 55 59.9 163 15 65 67.1 164 15 75 72.0 165 15 85 65.3 166 15 95 73.3 167 15 105 63.0 168 15 115 58.2 169 15 125 51.0 170 15 135 58.1 171 15 145 48.0 172 15 155 50.1 173 15 165 54.5 174 15 175 45.0 175 15 185 40.8 176 15 195 45.9 177 15 205 47.4 178 15 215 51.9 179 15 225 56.4 180 15 235 71.1 181 15 245 50.8 182 15 255 59.6 183 15 265 65.0 184 15 275 58.8 185 15 285 54.2 186 15 295 48.9 187 15 305 53.3 188 15 315 53.0 189 15 325 53.5 190 15 335 62.8 191 15 345 68.4 193 5 5 74.2 197 5 45 42.6 198 5 55 50.7 199 5 65 62.4 200 5 75 67.7 201 5 85 68.3 202 5 95 76.3 203 5 105 66.5 204 5 115 63.7 205 5 125 63.1 206 5 135 65.7 207 5 145 54.3 208 5 155 55.1 209 5 165 57.1 219 5 265 68.7 220 5 275 71.8 221 5 285 78.7 223 5 305 56.7 224 5 315 49.5 225 5 325 48.0 226 5 335 62.2 227 5 345 73.5 228 5 355 70.7 229 -5 5 61.0 230 -5 15 61.0 233 -5 45 46.5 234 -5 55 50.5 235 -5 65 66.7 236 -5 75 62.9 237 -5 85 73.5 238 -5 95 72.1 239 -5 105 52.0 240 -5 115 49.2 241 -5 125 46.6 242 -5 135 54.3 243 -5 145 63.0 244 -5 155 56.6 247 -5 185 60.5 255 -5 265 57.2 256 -5 275 73.2 261 -5 325 46.1 262 -5 335 41.5 264 -5 355 54.1 265 -15 5 67.9 266 -15 15 75.6 269 -15 45 34.5 270 -15 55 48.6 271 -15 65 45.8 272 -15 75 51.3 273 -15 85 58.5 274 -15 95 59.3 275 -15 105 53.0 279 -15 145 58.8 280 -15 155 52.1 281 -15 165 66.9 282 -15 175 58.3 283 -15 185 48.9 286 -15 215 49.8 292 -15 275 69.7 293 -15 285 74.5 297 -15 325 46.6 299 -15 345 56.9 300 -15 355 64.6 301 -25 5 59.2 302 -25 15 54.4 304 -25 35 49.4 305 -25 45 46.7 306 -25 55 56.2 310 -25 95 58.4 311 -25 105 57.4 312 -25 115 48.2 316 -25 155 55.3 317 -25 165 55.9 318 -25 175 56.8 319 -25 185 62.9 321 -25 205 72.9 322 -25 215 64.5 323 -25 225 60.9 332 -25 315 52.5 333 -25 325 44.7 336 -25 355 64.3 337 -35 5 51.9 338 -35 15 57.6 339 -35 25 60.8 340 -35 35 52.4 346 -35 95 55.7 348 -35 115 59.0 349 -35 125 65.7 350 -35 135 69.3 351 -35 145 56.8 352 -35 155 62.1 353 -35 165 62.2 354 -35 175 64.2 355 -35 185 65.0 356 -35 195 61.3 357 -35 205 77.0 364 -35 275 45.7 367 -35 305 60.1 368 -35 315 62.1 390 -45 175 62.5 402 -45 295 61.6 403 -45 305 61.5 424 -55 310 70.7 425 -55 330 43.8