Total Cloud Cover Average Cloud Amount (%) July (1954 - 1997) Night, Ship Observations Only Global Average: 67.5 Zonal Averages 15 zones Lat.N Average 85 82.3 75 81.0 65 80.7 55 84.9 45 82.3 35 63.5 25 57.7 15 64.9 5 67.7 -5 58.8 -15 61.8 -25 62.6 -35 67.3 -45 73.0 -55 78.1 Grid Box Averages 325 filled boxes Box # Lat.N Lon.E Average 1 85 60 83.3 2 85 180 86.2 3 85 300 75.0 4 75 20 84.7 5 75 60 80.2 6 75 100 77.3 7 75 140 88.5 8 75 180 81.8 9 75 220 75.2 10 75 260 74.8 11 75 300 70.7 12 75 340 88.5 13 65 10 83.7 14 65 30 74.9 15 65 50 73.7 16 65 70 81.2 20 65 150 69.1 21 65 170 84.7 22 65 190 83.9 23 65 210 77.5 24 65 230 65.6 25 65 250 69.3 26 65 270 67.2 27 65 290 69.8 28 65 310 79.6 29 65 330 85.0 30 65 350 87.5 31 55 10 66.5 32 55 30 53.4 37 55 130 75.1 38 55 150 83.3 39 55 170 89.9 40 55 190 93.8 41 55 210 90.3 42 55 230 86.3 44 55 270 62.1 45 55 290 71.6 46 55 310 83.3 47 55 330 90.6 48 55 350 80.3 49 45 5 28.6 50 45 15 23.7 51 45 25 26.4 52 45 35 28.3 54 45 55 43.3 62 45 135 75.9 63 45 145 85.4 64 45 155 93.1 65 45 165 96.4 66 45 175 97.2 67 45 185 96.8 68 45 195 94.8 69 45 205 93.6 70 45 215 93.0 71 45 225 89.8 72 45 235 70.0 77 45 285 60.3 78 45 295 66.2 79 45 305 71.8 80 45 315 79.7 81 45 325 79.8 82 45 335 82.0 83 45 345 77.4 84 45 355 63.1 85 35 5 30.1 86 35 15 14.3 87 35 25 9.8 88 35 35 17.7 96 35 115 59.0 97 35 125 65.5 98 35 135 64.2 99 35 145 75.5 100 35 155 80.4 101 35 165 78.7 102 35 175 71.4 103 35 185 71.3 104 35 195 70.4 105 35 205 73.0 106 35 215 79.0 107 35 225 83.2 108 35 235 74.5 109 35 245 69.2 112 35 275 53.6 113 35 285 57.8 114 35 295 60.4 115 35 305 56.7 116 35 315 49.6 117 35 325 53.0 118 35 335 65.0 119 35 345 67.0 120 35 355 35.7 124 25 35 11.5 125 25 45 6.5 126 25 55 29.4 127 25 65 71.9 129 25 85 77.7 131 25 105 68.8 132 25 115 58.0 133 25 125 53.9 134 25 135 56.3 135 25 145 56.4 136 25 155 58.1 137 25 165 55.3 138 25 175 53.3 139 25 185 52.5 140 25 195 53.8 141 25 205 58.4 142 25 215 74.3 143 25 225 85.9 144 25 235 86.5 145 25 245 59.6 146 25 255 56.9 147 25 265 49.3 148 25 275 49.8 149 25 285 51.9 150 25 295 49.5 151 25 305 44.8 152 25 315 46.6 153 25 325 54.5 154 25 335 65.5 155 25 345 52.8 160 15 35 34.0 161 15 45 46.5 162 15 55 44.6 163 15 65 74.0 164 15 75 80.9 165 15 85 78.3 166 15 95 83.3 167 15 105 68.7 168 15 115 67.1 169 15 125 64.4 170 15 135 66.2 171 15 145 63.3 172 15 155 61.0 173 15 165 58.1 174 15 175 57.5 175 15 185 55.9 176 15 195 58.6 177 15 205 57.8 178 15 215 69.3 179 15 225 77.5 180 15 235 80.7 181 15 245 67.7 182 15 255 67.9 183 15 265 69.4 184 15 275 64.5 185 15 285 58.7 186 15 295 53.8 187 15 305 55.5 188 15 315 59.7 189 15 325 69.0 190 15 335 71.0 191 15 345 62.6 193 5 5 80.3 197 5 45 51.2 198 5 55 46.7 199 5 65 60.3 200 5 75 70.0 201 5 85 69.9 202 5 95 77.7 203 5 105 68.5 204 5 115 67.8 205 5 125 69.4 206 5 135 72.0 207 5 145 67.2 208 5 155 68.5 209 5 165 65.6 210 5 175 67.6 211 5 185 65.5 212 5 195 64.2 213 5 205 60.7 214 5 215 62.4 215 5 225 63.6 216 5 235 66.2 217 5 245 74.3 218 5 255 76.6 219 5 265 81.0 220 5 275 81.7 221 5 285 79.7 223 5 305 60.9 224 5 315 60.6 225 5 325 56.8 226 5 335 67.1 227 5 345 75.1 228 5 355 73.5 229 -5 5 69.9 230 -5 15 51.8 233 -5 45 55.4 234 -5 55 63.3 235 -5 65 69.9 236 -5 75 69.2 237 -5 85 69.1 238 -5 95 70.7 239 -5 105 56.8 240 -5 115 43.8 241 -5 125 50.3 242 -5 135 60.0 243 -5 145 68.7 244 -5 155 73.7 245 -5 165 67.1 246 -5 175 57.3 247 -5 185 55.6 248 -5 195 52.5 249 -5 205 44.7 250 -5 215 42.4 251 -5 225 44.5 252 -5 235 43.1 253 -5 245 44.5 254 -5 255 62.2 255 -5 265 75.9 256 -5 275 87.1 257 -5 285 79.3 260 -5 315 47.7 261 -5 325 54.6 262 -5 335 50.0 263 -5 345 44.7 264 -5 355 58.7 265 -15 5 82.7 266 -15 15 65.3 268 -15 35 38.9 269 -15 45 42.5 270 -15 55 58.2 271 -15 65 62.6 272 -15 75 64.3 273 -15 85 69.3 274 -15 95 71.0 275 -15 105 59.4 276 -15 115 35.6 277 -15 125 20.2 278 -15 135 47.6 279 -15 145 54.3 280 -15 155 66.5 281 -15 165 68.8 282 -15 175 70.9 283 -15 185 64.5 284 -15 195 54.3 285 -15 205 51.3 286 -15 215 52.8 287 -15 225 50.5 288 -15 235 52.9 289 -15 245 55.7 290 -15 255 65.2 291 -15 265 80.9 292 -15 275 89.0 293 -15 285 85.2 297 -15 325 54.9 298 -15 335 54.4 299 -15 345 62.9 300 -15 355 79.3 301 -25 5 71.9 302 -25 15 42.6 304 -25 35 40.0 305 -25 45 50.8 306 -25 55 54.4 307 -25 65 61.8 308 -25 75 62.0 309 -25 85 70.9 310 -25 95 68.4 311 -25 105 61.4 312 -25 115 41.5 315 -25 145 32.3 316 -25 155 48.2 317 -25 165 59.1 318 -25 175 65.5 319 -25 185 65.4 320 -25 195 67.8 321 -25 205 66.7 322 -25 215 67.2 323 -25 225 66.0 324 -25 235 64.0 325 -25 245 62.7 328 -25 275 70.4 329 -25 285 73.5 332 -25 315 53.2 333 -25 325 58.4 334 -25 335 62.1 335 -25 345 66.5 336 -25 355 69.8 337 -35 5 76.4 338 -35 15 50.7 339 -35 25 39.6 340 -35 35 46.9 341 -35 45 61.1 342 -35 55 66.1 343 -35 65 71.8 344 -35 75 73.0 345 -35 85 74.9 346 -35 95 70.3 347 -35 105 66.5 348 -35 115 65.1 349 -35 125 64.4 350 -35 135 66.4 351 -35 145 65.8 352 -35 155 56.2 353 -35 165 65.1 354 -35 175 62.0 355 -35 185 68.1 356 -35 195 68.3 357 -35 205 69.7 358 -35 215 74.8 359 -35 225 72.2 364 -35 275 74.2 365 -35 285 65.9 367 -35 305 65.3 368 -35 315 65.2 369 -35 325 76.9 370 -35 335 76.5 371 -35 345 73.5 372 -35 355 75.8 387 -45 145 64.5 388 -45 155 72.1 389 -45 165 75.6 390 -45 175 63.4 391 -45 185 75.2 393 -45 205 72.2 397 -45 245 78.7 400 -45 275 79.3 401 -45 285 79.8 402 -45 295 67.7 403 -45 305 71.2 404 -45 315 75.5 417 -55 170 83.2 423 -55 290 76.2 424 -55 310 76.7 425 -55 330 75.9