Cumulonimbus Amount-When-Present (%) June, July, August (1954 - 1997) Day, Ship Observations Only Global Average: 56.2 Zonal Averages 15 zones Lat.N Average 85 66.8 75 78.6 65 70.4 55 67.0 45 62.2 35 50.7 25 44.9 15 49.6 5 53.3 -5 49.4 -15 53.1 -25 53.4 -35 57.3 -45 64.5 -55 70.0 Grid Box Averages 330 filled boxes Box # Lat.N Lon.E Average 1 85 60 66.8 4 75 20 77.5 5 75 60 79.9 6 75 100 79.6 7 75 140 78.5 11 75 300 67.9 12 75 340 80.8 13 65 10 69.8 14 65 30 79.7 15 65 50 76.3 21 65 170 72.3 22 65 190 65.6 23 65 210 56.0 27 65 290 66.7 28 65 310 66.3 29 65 330 69.5 30 65 350 71.3 31 55 10 59.0 32 55 30 69.6 38 55 150 75.2 39 55 170 75.9 40 55 190 70.6 41 55 210 66.9 42 55 230 66.6 45 55 290 63.4 46 55 310 68.2 47 55 330 70.8 48 55 350 60.8 49 45 5 40.2 50 45 15 44.5 51 45 25 60.9 52 45 35 71.3 53 45 45 61.8 54 45 55 53.0 62 45 135 75.6 63 45 145 75.5 64 45 155 67.3 65 45 165 69.5 66 45 175 70.8 67 45 185 70.6 68 45 195 68.3 69 45 205 65.5 70 45 215 65.3 71 45 225 62.9 72 45 235 59.6 77 45 285 55.5 78 45 295 63.3 79 45 305 59.0 80 45 315 59.6 81 45 325 58.9 82 45 335 59.6 83 45 345 58.0 84 45 355 55.8 85 35 5 45.3 86 35 15 44.5 87 35 25 40.2 88 35 35 42.7 97 35 125 67.0 98 35 135 50.5 99 35 145 53.2 100 35 155 50.8 101 35 165 48.1 102 35 175 50.7 103 35 185 47.7 104 35 195 49.4 105 35 205 51.7 106 35 215 55.6 107 35 225 58.7 108 35 235 59.7 109 35 245 54.7 112 35 275 41.2 113 35 285 47.9 114 35 295 50.0 115 35 305 47.3 116 35 315 45.6 117 35 325 47.7 118 35 335 52.6 119 35 345 54.0 120 35 355 44.6 124 25 35 41.4 126 25 55 47.4 127 25 65 61.7 128 25 75 57.1 129 25 85 62.6 130 25 95 59.0 131 25 105 45.3 132 25 115 47.2 133 25 125 45.5 134 25 135 42.6 135 25 145 43.8 136 25 155 43.7 137 25 165 43.3 138 25 175 43.1 139 25 185 43.0 140 25 195 44.2 141 25 205 47.8 142 25 215 53.2 143 25 225 59.7 144 25 235 65.2 145 25 245 44.4 146 25 255 41.5 147 25 265 40.5 148 25 275 39.7 149 25 285 41.9 150 25 295 43.1 151 25 305 43.3 152 25 315 43.5 153 25 325 47.6 154 25 335 53.0 155 25 345 52.5 160 15 35 40.3 161 15 45 43.8 162 15 55 54.6 163 15 65 57.6 164 15 75 60.3 165 15 85 62.6 166 15 95 59.7 167 15 105 35.4 168 15 115 49.3 169 15 125 47.1 170 15 135 47.8 171 15 145 47.3 172 15 155 46.4 173 15 165 44.9 174 15 175 44.9 175 15 185 48.4 176 15 195 47.9 177 15 205 50.5 178 15 215 52.4 179 15 225 55.5 180 15 235 57.2 181 15 245 52.8 182 15 255 45.1 183 15 265 46.0 184 15 275 46.2 185 15 285 44.4 186 15 295 43.6 187 15 305 48.9 188 15 315 49.0 189 15 325 53.6 190 15 335 58.9 191 15 345 61.1 193 5 5 63.1 197 5 45 47.9 198 5 55 49.6 199 5 65 52.6 200 5 75 51.2 201 5 85 49.0 202 5 95 49.3 203 5 105 49.5 204 5 115 48.8 205 5 125 48.6 206 5 135 48.7 207 5 145 50.2 208 5 155 49.9 209 5 165 49.0 210 5 175 50.6 211 5 185 54.5 212 5 195 50.4 213 5 205 52.6 214 5 215 55.1 215 5 225 55.2 216 5 235 56.1 217 5 245 60.0 218 5 255 60.4 219 5 265 59.3 220 5 275 58.8 221 5 285 59.1 223 5 305 51.0 224 5 315 50.3 225 5 325 53.9 226 5 335 60.4 227 5 345 66.0 228 5 355 65.0 229 -5 5 57.1 230 -5 15 66.8 232 -5 35 54.6 233 -5 45 47.7 234 -5 55 52.3 235 -5 65 53.5 236 -5 75 53.6 237 -5 85 50.7 238 -5 95 52.4 239 -5 105 48.9 240 -5 115 42.3 241 -5 125 44.3 242 -5 135 51.9 243 -5 145 47.3 244 -5 155 51.1 245 -5 165 51.7 246 -5 175 46.4 247 -5 185 49.4 248 -5 195 46.7 249 -5 205 46.1 250 -5 215 44.5 251 -5 225 45.0 252 -5 235 41.8 253 -5 245 44.1 254 -5 255 47.3 255 -5 265 54.1 256 -5 275 65.1 260 -5 315 45.0 261 -5 325 52.1 262 -5 335 49.8 263 -5 345 48.0 264 -5 355 50.9 265 -15 5 65.2 266 -15 15 63.7 268 -15 35 49.8 269 -15 45 44.7 270 -15 55 53.3 271 -15 65 53.6 272 -15 75 53.4 273 -15 85 56.8 274 -15 95 57.0 275 -15 105 54.9 276 -15 115 50.5 277 -15 125 42.0 278 -15 135 52.0 279 -15 145 52.6 280 -15 155 52.5 281 -15 165 55.0 282 -15 175 54.4 283 -15 185 54.3 284 -15 195 51.8 285 -15 205 51.8 286 -15 215 50.5 287 -15 225 49.2 288 -15 235 48.6 289 -15 245 50.3 290 -15 255 52.1 291 -15 265 58.3 292 -15 275 65.5 293 -15 285 67.5 297 -15 325 50.9 298 -15 335 50.4 299 -15 345 51.9 300 -15 355 58.4 301 -25 5 56.1 302 -25 15 51.8 304 -25 35 50.7 305 -25 45 50.1 306 -25 55 50.5 307 -25 65 53.6 308 -25 75 50.9 309 -25 85 55.7 310 -25 95 54.2 311 -25 105 55.2 312 -25 115 55.5 315 -25 145 56.4 316 -25 155 53.6 317 -25 165 50.4 318 -25 175 53.0 319 -25 185 54.0 320 -25 195 52.5 321 -25 205 54.6 322 -25 215 55.9 323 -25 225 55.4 324 -25 235 50.2 325 -25 245 51.5 326 -25 255 51.7 327 -25 265 53.4 328 -25 275 57.9 329 -25 285 57.2 332 -25 315 54.2 333 -25 325 52.9 334 -25 335 55.4 335 -25 345 53.1 336 -25 355 55.7 337 -35 5 56.2 338 -35 15 53.4 339 -35 25 53.2 340 -35 35 54.0 341 -35 45 54.6 342 -35 55 56.4 343 -35 65 58.9 344 -35 75 57.7 345 -35 85 60.0 346 -35 95 58.0 347 -35 105 57.5 348 -35 115 60.3 349 -35 125 56.0 350 -35 135 58.3 351 -35 145 59.4 352 -35 155 55.2 353 -35 165 53.3 354 -35 175 52.2 355 -35 185 54.9 356 -35 195 52.6 357 -35 205 54.4 358 -35 215 54.9 359 -35 225 51.7 360 -35 235 58.4 362 -35 255 67.2 363 -35 265 68.8 364 -35 275 66.8 365 -35 285 60.5 367 -35 305 69.6 368 -35 315 65.0 369 -35 325 59.0 370 -35 335 55.8 371 -35 345 56.4 372 -35 355 58.6 378 -45 55 66.2 379 -45 65 69.9 380 -45 75 74.0 386 -45 135 58.4 387 -45 145 57.9 388 -45 155 59.8 389 -45 165 61.5 390 -45 175 57.0 391 -45 185 62.3 392 -45 195 58.5 393 -45 205 62.0 394 -45 215 62.7 397 -45 245 74.1 398 -45 255 68.4 400 -45 275 67.1 401 -45 285 66.2 402 -45 295 65.8 403 -45 305 65.2 404 -45 315 63.7 405 -45 325 74.0 411 -55 50 75.5 412 -55 70 72.7 417 -55 170 78.7 422 -55 270 61.1 423 -55 290 67.0 424 -55 310 67.5 425 -55 330 69.0