Cumulonimbus Amount-When-Present (%) September, October, November (1954 - 1997) , Ship Observations Only Global Average: 58.0 Zonal Averages 16 zones Lat.N Average 85 82.9 75 82.6 65 70.8 55 65.7 45 63.2 35 56.2 25 48.7 15 49.7 5 53.6 -5 50.8 -15 53.5 -25 54.7 -35 58.2 -45 61.8 -55 68.2 -65 75.3 Grid Box Averages 345 filled boxes Box # Lat.N Lon.E Average 1 85 60 82.9 4 75 20 79.1 5 75 60 85.1 6 75 100 91.8 7 75 140 78.5 8 75 180 80.7 10 75 260 70.6 11 75 300 70.7 12 75 340 87.3 13 65 10 67.6 14 65 30 82.9 15 65 50 79.5 21 65 170 75.6 22 65 190 76.0 23 65 210 70.0 26 65 270 74.8 27 65 290 80.7 28 65 310 66.6 29 65 330 68.0 30 65 350 72.8 31 55 10 62.8 32 55 30 73.2 38 55 150 77.7 39 55 170 68.0 40 55 190 63.6 41 55 210 61.1 42 55 230 63.3 44 55 270 64.4 45 55 290 65.8 46 55 310 71.9 47 55 330 66.2 48 55 350 61.3 49 45 5 54.0 50 45 15 56.6 51 45 25 73.4 52 45 35 80.0 53 45 45 70.3 54 45 55 69.3 62 45 135 74.8 63 45 145 74.4 64 45 155 66.4 65 45 165 62.5 66 45 175 63.2 67 45 185 59.9 68 45 195 59.5 69 45 205 59.1 70 45 215 60.4 71 45 225 60.1 72 45 235 59.3 77 45 285 62.7 78 45 295 70.6 79 45 305 68.1 80 45 315 68.1 81 45 325 63.5 82 45 335 61.7 83 45 345 60.7 84 45 355 60.5 85 35 5 55.1 86 35 15 53.3 87 35 25 52.2 88 35 35 48.6 97 35 125 70.4 98 35 135 59.7 99 35 145 59.2 100 35 155 58.3 101 35 165 56.1 102 35 175 56.8 103 35 185 56.3 104 35 195 56.2 105 35 205 56.7 106 35 215 55.7 107 35 225 57.0 108 35 235 56.5 109 35 245 55.5 112 35 275 49.6 113 35 285 52.6 114 35 295 56.1 115 35 305 55.0 116 35 315 53.5 117 35 325 54.5 118 35 335 57.1 119 35 345 56.4 120 35 355 52.2 124 25 35 44.7 126 25 55 40.4 127 25 65 49.6 129 25 85 54.2 130 25 95 48.4 132 25 115 58.4 133 25 125 52.4 134 25 135 46.1 135 25 145 45.7 136 25 155 47.2 137 25 165 47.7 138 25 175 48.6 139 25 185 47.9 140 25 195 48.4 141 25 205 49.8 142 25 215 52.2 143 25 225 54.5 144 25 235 57.7 145 25 245 47.4 146 25 255 44.4 147 25 265 45.9 148 25 275 44.3 149 25 285 46.2 150 25 295 47.4 151 25 305 49.6 152 25 315 50.0 153 25 325 51.2 154 25 335 53.3 155 25 345 51.5 160 15 35 45.0 161 15 45 37.3 162 15 55 48.3 163 15 65 49.5 164 15 75 51.5 165 15 85 56.8 166 15 95 54.1 167 15 105 47.4 168 15 115 51.1 169 15 125 47.6 170 15 135 47.7 171 15 145 47.2 172 15 155 49.5 173 15 165 48.6 174 15 175 49.3 175 15 185 48.8 176 15 195 50.3 177 15 205 52.0 178 15 215 54.5 179 15 225 56.5 180 15 235 56.8 181 15 245 52.5 182 15 255 47.1 183 15 265 45.8 184 15 275 47.2 185 15 285 45.3 186 15 295 44.2 187 15 305 47.9 188 15 315 49.5 189 15 325 51.6 190 15 335 55.7 191 15 345 54.1 193 5 5 59.0 197 5 45 44.3 198 5 55 47.5 199 5 65 50.5 200 5 75 51.3 201 5 85 51.9 202 5 95 53.5 203 5 105 51.2 204 5 115 51.2 205 5 125 48.9 206 5 135 47.3 207 5 145 49.7 208 5 155 50.0 209 5 165 53.2 210 5 175 52.2 211 5 185 53.6 212 5 195 52.5 213 5 205 55.1 214 5 215 57.9 215 5 225 55.5 216 5 235 59.3 217 5 245 62.9 218 5 255 59.8 219 5 265 59.7 220 5 275 59.5 221 5 285 55.2 222 5 295 45.2 223 5 305 46.9 224 5 315 48.2 225 5 325 53.5 226 5 335 60.4 227 5 345 59.6 228 5 355 59.4 229 -5 5 66.6 230 -5 15 66.4 232 -5 35 38.9 233 -5 45 47.2 234 -5 55 52.0 235 -5 65 51.9 236 -5 75 52.6 237 -5 85 51.1 238 -5 95 55.4 239 -5 105 53.4 240 -5 115 46.5 241 -5 125 42.5 242 -5 135 48.1 243 -5 145 49.3 244 -5 155 50.6 245 -5 165 50.8 246 -5 175 49.7 247 -5 185 48.4 248 -5 195 47.1 249 -5 205 43.1 250 -5 215 43.4 251 -5 225 45.7 252 -5 235 46.1 253 -5 245 49.3 254 -5 255 53.5 255 -5 265 59.1 256 -5 275 69.7 260 -5 315 43.9 261 -5 325 47.6 262 -5 335 48.3 263 -5 345 56.1 264 -5 355 63.0 265 -15 5 74.1 266 -15 15 63.8 268 -15 35 50.0 269 -15 45 43.8 270 -15 55 51.6 271 -15 65 52.6 272 -15 75 52.8 273 -15 85 54.5 274 -15 95 54.4 275 -15 105 52.1 276 -15 115 47.8 277 -15 125 38.0 278 -15 135 41.0 279 -15 145 46.6 280 -15 155 50.8 281 -15 165 54.3 282 -15 175 55.8 283 -15 185 52.5 284 -15 195 54.1 285 -15 205 52.6 286 -15 215 53.2 287 -15 225 50.8 288 -15 235 48.7 289 -15 245 49.8 290 -15 255 56.8 291 -15 265 60.6 292 -15 275 69.4 293 -15 285 67.4 297 -15 325 52.5 298 -15 335 52.1 299 -15 345 59.7 300 -15 355 68.7 301 -25 5 59.0 302 -25 15 52.3 304 -25 35 57.7 305 -25 45 53.2 306 -25 55 50.3 307 -25 65 50.3 308 -25 75 51.9 309 -25 85 52.8 310 -25 95 56.1 311 -25 105 58.2 312 -25 115 53.7 315 -25 145 50.0 316 -25 155 50.6 317 -25 165 52.2 318 -25 175 51.9 319 -25 185 53.6 320 -25 195 56.7 321 -25 205 54.5 322 -25 215 56.0 323 -25 225 55.5 324 -25 235 47.4 325 -25 245 53.2 326 -25 255 51.5 327 -25 265 61.7 328 -25 275 68.7 329 -25 285 60.8 332 -25 315 58.7 333 -25 325 58.9 334 -25 335 55.2 335 -25 345 57.0 336 -25 355 59.0 337 -35 5 59.7 338 -35 15 53.7 339 -35 25 56.8 340 -35 35 62.6 341 -35 45 55.8 342 -35 55 55.1 343 -35 65 61.2 344 -35 75 56.8 345 -35 85 57.6 346 -35 95 59.2 347 -35 105 62.3 348 -35 115 61.4 349 -35 125 59.6 350 -35 135 59.9 351 -35 145 61.5 352 -35 155 56.4 353 -35 165 54.4 354 -35 175 51.0 355 -35 185 52.9 356 -35 195 54.1 357 -35 205 56.0 358 -35 215 58.2 359 -35 225 57.8 360 -35 235 57.3 361 -35 245 66.0 363 -35 265 59.0 364 -35 275 66.5 365 -35 285 55.1 367 -35 305 60.1 368 -35 315 62.9 369 -35 325 59.8 370 -35 335 60.5 371 -35 345 56.3 372 -35 355 56.4 376 -45 35 77.0 378 -45 55 71.9 379 -45 65 65.8 380 -45 75 65.7 381 -45 85 60.4 382 -45 95 65.8 383 -45 105 57.2 384 -45 115 56.7 385 -45 125 55.4 386 -45 135 52.4 387 -45 145 56.2 388 -45 155 57.9 389 -45 165 64.0 390 -45 175 55.6 391 -45 185 59.2 392 -45 195 56.4 393 -45 205 59.9 394 -45 215 60.6 400 -45 275 68.4 401 -45 285 63.8 402 -45 295 63.8 403 -45 305 60.0 404 -45 315 67.4 405 -45 325 66.8 408 -45 355 60.8 411 -55 50 77.1 412 -55 70 69.3 414 -55 110 75.1 415 -55 130 65.5 416 -55 150 68.6 417 -55 170 73.7 421 -55 250 61.2 422 -55 270 61.9 423 -55 290 66.5 424 -55 310 69.6 425 -55 330 72.6 432 -65 110 83.7 433 -65 130 68.2 442 -65 310 78.7