Cumulus Frequency of Occurrence (%) September (1954 - 1997) Day, Ship Observations Only Global Average: 35.1 Zonal Averages 16 zones Lat.N Average 85 1.7 75 6.0 65 13.5 55 18.1 45 23.5 35 41.5 25 51.3 15 48.9 5 47.9 -5 52.9 -15 46.2 -25 39.8 -35 28.7 -45 18.3 -55 13.8 -65 8.5 Grid Box Averages 363 filled boxes Box # Lat.N Lon.E Average 1 85 60 3.6 2 85 180 0.3 3 85 300 1.3 4 75 20 11.1 5 75 60 9.8 6 75 100 4.2 7 75 140 4.0 8 75 180 2.9 9 75 220 2.4 10 75 260 4.2 11 75 300 7.7 12 75 340 7.8 13 65 10 17.0 14 65 30 17.5 15 65 50 15.2 16 65 70 13.2 20 65 150 22.6 21 65 170 16.6 22 65 190 12.2 23 65 210 15.4 24 65 230 10.1 25 65 250 9.5 26 65 270 7.7 27 65 290 7.9 28 65 310 10.3 29 65 330 15.3 30 65 350 16.1 31 55 10 24.4 32 55 30 25.2 37 55 130 17.1 38 55 150 18.9 39 55 170 18.0 40 55 190 14.2 41 55 210 19.1 42 55 230 21.9 44 55 270 11.3 45 55 290 16.3 46 55 310 15.9 47 55 330 18.5 48 55 350 20.3 49 45 5 27.2 50 45 15 30.0 51 45 25 27.2 52 45 35 29.4 53 45 45 20.1 54 45 55 17.3 62 45 135 27.4 63 45 145 22.9 64 45 155 18.9 65 45 165 18.8 66 45 175 16.6 67 45 185 16.2 68 45 195 17.3 69 45 205 19.5 70 45 215 20.4 71 45 225 24.7 72 45 235 21.0 77 45 285 20.3 78 45 295 23.7 79 45 305 28.3 80 45 315 26.7 81 45 325 31.3 82 45 335 31.3 83 45 345 29.1 84 45 355 27.1 85 35 5 31.5 86 35 15 40.1 87 35 25 32.7 88 35 35 42.3 90 35 55 24.9 96 35 115 19.4 97 35 125 29.3 98 35 135 41.4 99 35 145 37.3 100 35 155 38.5 101 35 165 41.0 102 35 175 38.6 103 35 185 38.0 104 35 195 40.8 105 35 205 41.8 106 35 215 38.9 107 35 225 33.8 108 35 235 23.5 109 35 245 17.0 112 35 275 43.9 113 35 285 41.0 114 35 295 48.9 115 35 305 52.7 116 35 315 57.0 117 35 325 55.7 118 35 335 51.3 119 35 345 47.8 120 35 355 25.1 124 25 35 9.7 125 25 45 2.3 126 25 55 14.8 127 25 65 45.0 128 25 75 50.4 129 25 85 43.6 130 25 95 48.9 131 25 105 41.4 132 25 115 40.3 133 25 125 49.1 134 25 135 51.1 135 25 145 53.1 136 25 155 55.9 137 25 165 57.1 138 25 175 59.9 139 25 185 59.6 140 25 195 64.3 141 25 205 62.0 142 25 215 50.8 143 25 225 35.9 144 25 235 27.2 145 25 245 32.7 146 25 255 50.4 147 25 265 47.8 148 25 275 47.2 149 25 285 52.4 150 25 295 57.7 151 25 305 63.4 152 25 315 63.6 153 25 325 62.7 154 25 335 55.8 155 25 345 25.8 160 15 35 24.9 161 15 45 30.9 162 15 55 34.6 163 15 65 57.7 164 15 75 49.1 165 15 85 45.6 166 15 95 41.9 167 15 105 47.0 168 15 115 45.4 169 15 125 42.6 170 15 135 41.2 171 15 145 42.4 172 15 155 46.2 173 15 165 54.4 174 15 175 55.9 175 15 185 55.8 176 15 195 60.9 177 15 205 56.1 178 15 215 49.1 179 15 225 44.8 180 15 235 43.3 181 15 245 48.8 182 15 255 43.8 183 15 265 39.5 184 15 275 44.1 185 15 285 54.6 186 15 295 58.9 187 15 305 58.6 188 15 315 55.2 189 15 325 50.1 190 15 335 48.1 191 15 345 35.2 193 5 5 32.7 197 5 45 62.4 198 5 55 60.4 199 5 65 64.6 200 5 75 52.9 201 5 85 49.0 202 5 95 41.4 203 5 105 43.8 204 5 115 42.1 205 5 125 46.8 206 5 135 47.7 207 5 145 45.7 208 5 155 47.9 209 5 165 51.8 210 5 175 51.7 211 5 185 53.7 212 5 195 55.8 213 5 205 55.2 214 5 215 47.0 215 5 225 48.6 216 5 235 49.0 217 5 245 43.9 218 5 255 32.7 219 5 265 26.4 220 5 275 27.0 221 5 285 28.1 223 5 305 61.6 224 5 315 60.8 225 5 325 60.8 226 5 335 50.0 227 5 345 38.8 228 5 355 34.1 229 -5 5 29.3 230 -5 15 17.4 232 -5 35 56.1 233 -5 45 64.8 234 -5 55 60.5 235 -5 65 57.1 236 -5 75 45.3 237 -5 85 43.7 238 -5 95 45.5 239 -5 105 50.8 240 -5 115 62.8 241 -5 125 58.5 242 -5 135 61.3 243 -5 145 47.4 244 -5 155 46.0 245 -5 165 53.5 246 -5 175 57.1 247 -5 185 63.2 248 -5 195 70.1 249 -5 205 69.3 250 -5 215 72.6 251 -5 225 72.0 252 -5 235 71.7 253 -5 245 58.6 254 -5 255 34.8 255 -5 265 20.6 256 -5 275 15.1 257 -5 285 6.6 260 -5 315 68.9 261 -5 325 68.4 262 -5 335 62.8 263 -5 345 48.1 264 -5 355 34.4 265 -15 5 10.7 266 -15 15 12.4 268 -15 35 57.4 269 -15 45 65.6 270 -15 55 61.5 271 -15 65 54.1 272 -15 75 46.6 273 -15 85 45.0 274 -15 95 47.9 275 -15 105 55.9 276 -15 115 40.4 277 -15 125 47.2 278 -15 135 64.9 279 -15 145 57.0 280 -15 155 56.6 281 -15 165 49.1 282 -15 175 45.5 283 -15 185 50.8 284 -15 195 54.6 285 -15 205 61.0 286 -15 215 63.0 287 -15 225 64.9 288 -15 235 68.2 289 -15 245 54.6 290 -15 255 41.0 291 -15 265 25.7 292 -15 275 11.5 293 -15 285 9.6 297 -15 325 57.5 298 -15 335 48.0 299 -15 345 31.1 300 -15 355 13.5 301 -25 5 23.1 302 -25 15 22.1 304 -25 35 45.2 305 -25 45 49.6 306 -25 55 55.1 307 -25 65 46.7 308 -25 75 41.9 309 -25 85 36.9 310 -25 95 40.7 311 -25 105 39.6 312 -25 115 37.4 315 -25 145 45.7 316 -25 155 53.7 317 -25 165 51.3 318 -25 175 47.1 319 -25 185 42.9 320 -25 195 38.5 321 -25 205 41.0 322 -25 215 40.4 323 -25 225 43.8 324 -25 235 50.1 325 -25 245 49.9 326 -25 255 43.9 327 -25 265 24.9 328 -25 275 25.8 329 -25 285 22.9 332 -25 315 26.9 333 -25 325 40.9 334 -25 335 40.5 335 -25 345 34.9 336 -25 355 27.9 337 -35 5 25.1 338 -35 15 29.8 339 -35 25 26.9 340 -35 35 32.3 341 -35 45 30.7 342 -35 55 29.2 343 -35 65 28.2 344 -35 75 25.1 345 -35 85 21.6 346 -35 95 25.7 347 -35 105 26.4 348 -35 115 30.9 349 -35 125 27.4 350 -35 135 26.8 351 -35 145 27.7 352 -35 155 36.8 353 -35 165 35.4 354 -35 175 37.0 355 -35 185 33.6 356 -35 195 30.5 357 -35 205 30.1 358 -35 215 29.6 359 -35 225 31.0 360 -35 235 30.8 361 -35 245 24.4 362 -35 255 29.5 363 -35 265 23.4 364 -35 275 23.6 365 -35 285 28.1 367 -35 305 20.0 368 -35 315 28.6 369 -35 325 28.2 370 -35 335 30.4 371 -35 345 28.2 372 -35 355 26.6 375 -45 25 24.7 376 -45 35 15.5 377 -45 45 9.0 378 -45 55 20.0 379 -45 65 14.8 380 -45 75 19.0 382 -45 95 11.6 383 -45 105 18.1 384 -45 115 22.6 385 -45 125 24.0 386 -45 135 23.2 387 -45 145 29.8 388 -45 155 24.4 389 -45 165 20.6 390 -45 175 24.0 391 -45 185 18.5 392 -45 195 18.0 393 -45 205 15.2 394 -45 215 17.4 395 -45 225 14.9 397 -45 245 8.8 400 -45 275 15.4 401 -45 285 23.2 402 -45 295 14.5 403 -45 305 13.8 404 -45 315 18.2 405 -45 325 15.7 408 -45 355 19.3 409 -55 10 21.9 411 -55 50 15.9 412 -55 70 8.7 414 -55 110 6.5 416 -55 150 24.0 417 -55 170 15.1 419 -55 210 10.2 420 -55 230 10.7 421 -55 250 9.3 422 -55 270 15.1 423 -55 290 16.2 424 -55 310 14.0 425 -55 330 12.0 432 -65 110 15.6 442 -65 310 4.1