Cumulus Frequency of Occurrence (%) September, October, November (1954 - 1997) Day, Ship Observations Only Global Average: 34.9 Zonal Averages 17 zones Lat.N Average 85 2.0 75 5.8 65 12.3 55 17.1 45 21.9 35 36.7 25 48.8 15 50.5 5 47.5 -5 53.3 -15 47.2 -25 41.9 -35 29.6 -45 18.5 -55 13.5 -65 8.2 -75 13.7 Grid Box Averages 394 filled boxes Box # Lat.N Lon.E Average 1 85 60 4.0 2 85 180 0.4 3 85 300 1.4 4 75 20 10.7 5 75 60 9.5 6 75 100 4.0 7 75 140 3.9 8 75 180 2.4 9 75 220 2.2 10 75 260 4.4 11 75 300 7.5 12 75 340 7.9 13 65 10 14.7 14 65 30 13.4 15 65 50 13.1 16 65 70 15.2 20 65 150 17.5 21 65 170 14.1 22 65 190 10.8 23 65 210 13.2 24 65 230 10.0 25 65 250 8.8 26 65 270 7.3 27 65 290 8.1 28 65 310 10.5 29 65 330 14.4 30 65 350 14.6 31 55 10 21.5 32 55 30 20.6 37 55 130 19.8 38 55 150 17.7 39 55 170 17.7 40 55 190 14.9 41 55 210 18.6 42 55 230 19.6 44 55 270 8.8 45 55 290 15.9 46 55 310 14.9 47 55 330 16.9 48 55 350 18.9 49 45 5 29.1 50 45 15 29.6 51 45 25 25.3 52 45 35 26.4 53 45 45 17.5 54 45 55 16.7 61 45 125 24.6 62 45 135 24.8 63 45 145 25.0 64 45 155 20.0 65 45 165 18.2 66 45 175 17.6 67 45 185 18.0 68 45 195 17.9 69 45 205 18.7 70 45 215 19.4 71 45 225 22.2 72 45 235 19.6 77 45 285 22.1 78 45 295 23.7 79 45 305 24.0 80 45 315 22.6 81 45 325 25.9 82 45 335 25.7 83 45 345 24.3 84 45 355 25.0 85 35 5 34.4 86 35 15 41.0 87 35 25 38.4 88 35 35 44.2 89 35 45 22.8 90 35 55 24.4 96 35 115 19.7 97 35 125 30.0 98 35 135 40.9 99 35 145 34.8 100 35 155 32.9 101 35 165 34.2 102 35 175 31.9 103 35 185 32.1 104 35 195 31.0 105 35 205 31.9 106 35 215 33.4 107 35 225 31.8 108 35 235 24.4 109 35 245 18.9 112 35 275 40.0 113 35 285 38.3 114 35 295 43.1 115 35 305 45.8 116 35 315 48.4 117 35 325 45.4 118 35 335 41.6 119 35 345 42.4 120 35 355 27.7 124 25 35 22.2 125 25 45 7.0 126 25 55 17.3 127 25 65 32.9 128 25 75 27.3 129 25 85 39.0 130 25 95 41.7 131 25 105 41.8 132 25 115 35.6 133 25 125 43.7 134 25 135 48.2 135 25 145 52.2 136 25 155 53.4 137 25 165 53.6 138 25 175 52.9 139 25 185 55.6 140 25 195 55.5 141 25 205 56.4 142 25 215 48.2 143 25 225 36.1 144 25 235 30.6 145 25 245 33.5 146 25 255 52.0 147 25 265 45.9 148 25 275 49.4 149 25 285 52.0 150 25 295 56.2 151 25 305 59.9 152 25 315 59.7 153 25 325 58.9 154 25 335 55.3 155 25 345 28.0 156 25 355 41.5 160 15 35 38.4 161 15 45 36.8 162 15 55 48.1 163 15 65 54.5 164 15 75 45.2 165 15 85 47.2 166 15 95 47.7 167 15 105 47.7 168 15 115 46.2 169 15 125 43.0 170 15 135 45.9 171 15 145 48.6 172 15 155 51.9 173 15 165 56.6 174 15 175 54.6 175 15 185 56.3 176 15 195 58.5 177 15 205 54.2 178 15 215 48.5 179 15 225 42.4 180 15 235 42.2 181 15 245 49.9 182 15 255 51.6 183 15 265 43.4 184 15 275 44.6 185 15 285 55.2 186 15 295 59.6 187 15 305 59.1 188 15 315 57.2 189 15 325 55.2 190 15 335 48.8 191 15 345 27.2 193 5 5 38.4 197 5 45 66.2 198 5 55 63.0 199 5 65 63.9 200 5 75 51.4 201 5 85 47.4 202 5 95 41.3 203 5 105 42.9 204 5 115 41.5 205 5 125 48.3 206 5 135 47.8 207 5 145 45.6 208 5 155 48.1 209 5 165 51.7 210 5 175 49.2 211 5 185 54.1 212 5 195 54.4 213 5 205 53.3 214 5 215 45.3 215 5 225 46.9 216 5 235 41.0 217 5 245 39.9 218 5 255 34.1 219 5 265 29.7 220 5 275 29.0 221 5 285 31.1 222 5 295 46.6 223 5 305 58.4 224 5 315 58.6 225 5 325 58.5 226 5 335 48.4 227 5 345 42.8 228 5 355 42.3 229 -5 5 32.1 230 -5 15 21.1 232 -5 35 55.5 233 -5 45 67.4 234 -5 55 61.5 235 -5 65 54.8 236 -5 75 47.2 237 -5 85 44.6 238 -5 95 44.0 239 -5 105 45.3 240 -5 115 57.0 241 -5 125 58.6 242 -5 135 61.5 243 -5 145 47.8 244 -5 155 46.7 245 -5 165 51.4 246 -5 175 54.9 247 -5 185 60.8 248 -5 195 67.5 249 -5 205 71.5 250 -5 215 71.6 251 -5 225 73.7 252 -5 235 73.2 253 -5 245 59.9 254 -5 255 41.4 255 -5 265 26.0 256 -5 275 18.1 257 -5 285 8.3 260 -5 315 67.6 261 -5 325 71.0 262 -5 335 62.5 263 -5 345 47.4 264 -5 355 34.6 265 -15 5 13.2 266 -15 15 16.8 268 -15 35 56.5 269 -15 45 64.8 270 -15 55 62.9 271 -15 65 55.4 272 -15 75 49.7 273 -15 85 47.4 274 -15 95 50.8 275 -15 105 55.2 276 -15 115 44.0 277 -15 125 54.0 278 -15 135 66.0 279 -15 145 61.9 280 -15 155 59.4 281 -15 165 51.0 282 -15 175 47.0 283 -15 185 49.2 284 -15 195 51.6 285 -15 205 53.7 286 -15 215 59.2 287 -15 225 65.2 288 -15 235 67.2 289 -15 245 56.3 290 -15 255 43.5 291 -15 265 29.6 292 -15 275 13.0 293 -15 285 10.2 297 -15 325 57.5 298 -15 335 51.3 299 -15 345 31.8 300 -15 355 13.9 301 -25 5 25.6 302 -25 15 22.8 304 -25 35 45.1 305 -25 45 48.6 306 -25 55 56.4 307 -25 65 49.6 308 -25 75 44.9 309 -25 85 42.0 310 -25 95 42.2 311 -25 105 38.2 312 -25 115 37.5 315 -25 145 57.9 316 -25 155 54.9 317 -25 165 52.3 318 -25 175 48.8 319 -25 185 45.1 320 -25 195 41.1 321 -25 205 42.2 322 -25 215 41.0 323 -25 225 43.9 324 -25 235 53.0 325 -25 245 54.9 326 -25 255 47.1 327 -25 265 36.3 328 -25 275 27.1 329 -25 285 22.7 332 -25 315 30.3 333 -25 325 40.5 334 -25 335 41.6 335 -25 345 37.1 336 -25 355 30.5 337 -35 5 27.4 338 -35 15 30.3 339 -35 25 29.2 340 -35 35 33.2 341 -35 45 32.4 342 -35 55 31.1 343 -35 65 29.3 344 -35 75 26.6 345 -35 85 25.3 346 -35 95 25.6 347 -35 105 25.5 348 -35 115 31.7 349 -35 125 27.6 350 -35 135 26.5 351 -35 145 28.6 352 -35 155 36.2 353 -35 165 34.5 354 -35 175 36.5 355 -35 185 35.0 356 -35 195 31.7 357 -35 205 30.8 358 -35 215 27.3 359 -35 225 30.8 360 -35 235 30.1 361 -35 245 24.4 362 -35 255 27.8 363 -35 265 27.9 364 -35 275 26.9 365 -35 285 27.7 366 -35 295 29.8 367 -35 305 23.9 368 -35 315 31.7 369 -35 325 32.9 370 -35 335 31.5 371 -35 345 27.4 372 -35 355 27.7 373 -45 5 12.9 374 -45 15 17.2 375 -45 25 18.3 376 -45 35 18.3 377 -45 45 15.3 378 -45 55 16.6 379 -45 65 16.5 380 -45 75 18.3 381 -45 85 19.0 382 -45 95 18.6 383 -45 105 18.6 384 -45 115 20.4 385 -45 125 24.2 386 -45 135 20.5 387 -45 145 28.1 388 -45 155 24.3 389 -45 165 21.7 390 -45 175 26.7 391 -45 185 19.0 392 -45 195 18.9 393 -45 205 18.3 394 -45 215 17.6 395 -45 225 17.5 396 -45 235 16.6 397 -45 245 16.3 398 -45 255 13.9 399 -45 265 16.9 400 -45 275 19.1 401 -45 285 23.2 402 -45 295 15.8 403 -45 305 14.5 404 -45 315 20.9 405 -45 325 15.9 406 -45 335 15.5 407 -45 345 15.3 408 -45 355 17.0 409 -55 10 12.8 410 -55 30 12.4 411 -55 50 12.5 412 -55 70 15.4 413 -55 90 12.3 414 -55 110 15.4 415 -55 130 11.6 416 -55 150 15.0 417 -55 170 15.0 418 -55 190 23.1 419 -55 210 12.7 420 -55 230 10.4 421 -55 250 9.4 422 -55 270 16.7 423 -55 290 16.0 424 -55 310 13.0 425 -55 330 14.4 426 -55 350 6.1 427 -65 10 4.5 429 -65 50 5.4 430 -65 70 7.7 431 -65 90 8.7 432 -65 110 9.9 433 -65 130 13.6 434 -65 150 12.4 435 -65 170 8.5 436 -65 190 12.4 441 -65 290 4.5 442 -65 310 7.9 443 -65 330 6.4 444 -65 350 6.9 449 -75 180 15.1 453 -75 340 11.4