Cumulonimbus Amount-When-Present (%) September, October, November (1954 - 1997) Day, Ship Observations Only Global Average: 56.8 Zonal Averages 16 zones Lat.N Average 85 79.9 75 81.2 65 69.9 55 64.6 45 62.0 35 55.1 25 47.9 15 48.7 5 52.4 -5 49.8 -15 51.6 -25 52.9 -35 56.4 -45 61.0 -55 67.9 -65 74.8 Grid Box Averages 328 filled boxes Box # Lat.N Lon.E Average 1 85 60 79.9 4 75 20 78.0 5 75 60 84.2 6 75 100 89.3 7 75 140 76.0 8 75 180 78.1 10 75 260 70.7 11 75 300 65.6 12 75 340 85.9 13 65 10 66.4 14 65 30 83.2 15 65 50 80.3 21 65 170 73.7 22 65 190 76.8 23 65 210 61.0 26 65 270 71.6 27 65 290 77.9 28 65 310 65.1 29 65 330 67.3 30 65 350 71.9 31 55 10 61.0 32 55 30 72.5 38 55 150 75.8 39 55 170 66.8 40 55 190 62.2 41 55 210 61.0 42 55 230 63.5 45 55 290 67.9 46 55 310 70.3 47 55 330 64.8 48 55 350 60.2 49 45 5 52.6 50 45 15 53.2 51 45 25 73.9 52 45 35 76.7 53 45 45 71.5 54 45 55 67.5 62 45 135 73.7 63 45 145 72.8 64 45 155 65.0 65 45 165 61.2 66 45 175 60.9 67 45 185 59.5 68 45 195 59.6 69 45 205 58.9 70 45 215 60.1 71 45 225 60.4 72 45 235 58.4 77 45 285 60.1 78 45 295 67.0 79 45 305 65.8 80 45 315 66.9 81 45 325 61.8 82 45 335 60.2 83 45 345 59.8 84 45 355 59.2 85 35 5 53.9 86 35 15 51.9 87 35 25 49.9 88 35 35 46.9 97 35 125 69.8 98 35 135 59.0 99 35 145 58.2 100 35 155 56.6 101 35 165 55.2 102 35 175 56.2 103 35 185 55.6 104 35 195 55.6 105 35 205 55.0 106 35 215 54.6 107 35 225 56.0 108 35 235 54.9 109 35 245 48.8 112 35 275 48.4 113 35 285 52.1 114 35 295 54.9 115 35 305 54.3 116 35 315 53.0 117 35 325 53.5 118 35 335 55.2 119 35 345 54.7 120 35 355 50.8 124 25 35 42.3 126 25 55 35.7 127 25 65 47.9 129 25 85 55.8 132 25 115 56.1 133 25 125 51.4 134 25 135 45.5 135 25 145 45.3 136 25 155 46.0 137 25 165 46.3 138 25 175 47.9 139 25 185 47.3 140 25 195 47.8 141 25 205 49.1 142 25 215 50.9 143 25 225 53.1 144 25 235 56.5 145 25 245 44.1 146 25 255 43.1 147 25 265 46.0 148 25 275 44.4 149 25 285 45.5 150 25 295 46.8 151 25 305 48.3 152 25 315 48.6 153 25 325 51.2 154 25 335 51.2 155 25 345 48.8 160 15 35 42.3 161 15 45 33.7 162 15 55 44.9 163 15 65 48.3 164 15 75 48.9 165 15 85 56.7 166 15 95 53.9 167 15 105 47.0 168 15 115 50.3 169 15 125 47.1 170 15 135 47.4 171 15 145 46.8 172 15 155 47.1 173 15 165 47.5 174 15 175 48.6 175 15 185 49.2 176 15 195 49.2 177 15 205 49.4 178 15 215 53.3 179 15 225 53.8 180 15 235 56.5 181 15 245 52.0 182 15 255 44.2 183 15 265 43.5 184 15 275 47.3 185 15 285 44.5 186 15 295 43.5 187 15 305 47.3 188 15 315 49.2 189 15 325 50.7 190 15 335 54.3 191 15 345 53.0 193 5 5 59.4 197 5 45 42.4 198 5 55 46.2 199 5 65 49.9 200 5 75 49.6 201 5 85 51.5 202 5 95 52.3 203 5 105 51.4 204 5 115 50.1 205 5 125 47.1 206 5 135 46.4 207 5 145 49.0 208 5 155 49.3 209 5 165 52.0 210 5 175 50.0 211 5 185 52.0 212 5 195 52.5 213 5 205 54.1 214 5 215 56.1 215 5 225 55.6 216 5 235 57.0 217 5 245 62.8 218 5 255 58.6 219 5 265 58.2 220 5 275 59.3 221 5 285 56.4 223 5 305 46.1 224 5 315 47.1 225 5 325 51.2 226 5 335 58.5 227 5 345 58.0 228 5 355 57.8 229 -5 5 65.9 230 -5 15 68.2 232 -5 35 39.6 233 -5 45 45.0 234 -5 55 51.0 235 -5 65 52.4 236 -5 75 52.6 237 -5 85 51.2 238 -5 95 56.4 239 -5 105 52.9 240 -5 115 44.6 241 -5 125 39.8 242 -5 135 45.6 243 -5 145 48.2 244 -5 155 48.7 245 -5 165 50.3 246 -5 175 51.1 247 -5 185 49.1 248 -5 195 46.9 249 -5 205 45.2 250 -5 215 43.7 251 -5 225 43.4 252 -5 235 42.0 253 -5 245 47.9 254 -5 255 50.0 255 -5 265 53.5 256 -5 275 65.8 260 -5 315 41.6 261 -5 325 46.2 262 -5 335 47.8 263 -5 345 53.8 264 -5 355 58.8 265 -15 5 69.5 266 -15 15 64.0 268 -15 35 48.2 269 -15 45 41.4 270 -15 55 49.5 271 -15 65 50.9 272 -15 75 51.2 273 -15 85 54.2 274 -15 95 55.0 275 -15 105 50.2 276 -15 115 49.5 277 -15 125 37.3 278 -15 135 40.6 279 -15 145 46.2 280 -15 155 49.5 281 -15 165 54.1 282 -15 175 54.0 283 -15 185 52.2 284 -15 195 51.4 285 -15 205 51.3 286 -15 215 51.1 287 -15 225 48.9 288 -15 235 44.9 289 -15 245 49.6 290 -15 255 52.2 291 -15 265 55.4 292 -15 275 65.6 293 -15 285 67.5 297 -15 325 51.0 298 -15 335 51.1 299 -15 345 54.8 300 -15 355 64.5 301 -25 5 55.7 302 -25 15 52.6 304 -25 35 54.2 305 -25 45 48.8 306 -25 55 48.0 307 -25 65 49.4 308 -25 75 47.8 309 -25 85 51.3 310 -25 95 53.4 311 -25 105 56.3 312 -25 115 51.5 315 -25 145 40.4 316 -25 155 49.9 317 -25 165 49.6 318 -25 175 52.3 319 -25 185 53.6 320 -25 195 56.3 321 -25 205 53.6 322 -25 215 52.8 323 -25 225 52.8 324 -25 235 47.9 325 -25 245 50.5 326 -25 255 51.2 327 -25 265 59.0 328 -25 275 62.8 329 -25 285 58.0 332 -25 315 57.0 333 -25 325 56.9 334 -25 335 53.7 335 -25 345 55.7 336 -25 355 55.9 337 -35 5 58.0 338 -35 15 53.2 339 -35 25 53.5 340 -35 35 58.0 341 -35 45 56.7 342 -35 55 54.4 343 -35 65 56.9 344 -35 75 54.8 345 -35 85 57.2 346 -35 95 58.5 347 -35 105 59.2 348 -35 115 59.6 349 -35 125 57.0 350 -35 135 58.6 351 -35 145 59.5 352 -35 155 55.6 353 -35 165 53.1 354 -35 175 48.3 355 -35 185 52.1 356 -35 195 52.7 357 -35 205 56.5 358 -35 215 54.9 359 -35 225 55.4 360 -35 235 57.6 364 -35 275 66.9 365 -35 285 53.9 367 -35 305 57.1 368 -35 315 60.6 369 -35 325 63.5 370 -35 335 57.9 371 -35 345 55.1 372 -35 355 55.1 378 -45 55 74.3 379 -45 65 70.9 380 -45 75 61.4 383 -45 105 61.5 384 -45 115 55.6 386 -45 135 57.7 387 -45 145 55.8 388 -45 155 55.6 389 -45 165 62.8 390 -45 175 53.1 391 -45 185 57.5 392 -45 195 58.9 393 -45 205 60.3 394 -45 215 56.4 401 -45 285 64.0 402 -45 295 62.8 403 -45 305 61.5 404 -45 315 64.0 405 -45 325 69.3 411 -55 50 74.1 417 -55 170 71.3 422 -55 270 60.5 423 -55 290 64.3 424 -55 310 68.2 425 -55 330 73.7 432 -65 110 84.4 433 -65 130 67.9