Cumulus Frequency of Occurrence (%) April (1954 - 1997) , Ship Observations Only Global Average: 33.8 Zonal Averages 17 zones Lat.N Average 85 3.7 75 5.9 65 13.9 55 14.2 45 15.8 35 25.6 25 40.2 15 51.8 5 48.2 -5 53.0 -15 51.1 -25 44.1 -35 30.5 -45 17.4 -55 12.0 -65 5.8 -75 5.2 Grid Box Averages 382 filled boxes Box # Lat.N Lon.E Average 1 85 60 8.4 2 85 180 0.7 3 85 300 1.6 4 75 20 13.9 5 75 60 7.6 6 75 100 8.9 7 75 140 2.2 8 75 180 1.1 9 75 220 0.5 11 75 300 9.4 12 75 340 8.4 13 65 10 15.6 14 65 30 12.9 15 65 50 9.3 21 65 170 10.6 22 65 190 9.4 23 65 210 10.7 29 65 330 15.4 30 65 350 16.3 31 55 10 14.8 32 55 30 11.4 38 55 150 11.4 39 55 170 12.8 40 55 190 12.1 41 55 210 14.3 42 55 230 17.8 46 55 310 16.6 47 55 330 14.8 48 55 350 15.7 49 45 5 21.9 50 45 15 19.8 51 45 25 11.8 52 45 35 11.6 53 45 45 10.8 54 45 55 8.3 61 45 125 5.9 62 45 135 11.1 63 45 145 12.4 64 45 155 10.6 65 45 165 9.8 66 45 175 11.8 67 45 185 13.1 68 45 195 12.9 69 45 205 14.3 70 45 215 16.7 71 45 225 19.6 72 45 235 22.3 77 45 285 10.0 78 45 295 12.4 79 45 305 13.1 80 45 315 16.6 81 45 325 21.9 82 45 335 21.4 83 45 345 22.9 84 45 355 24.1 85 35 5 23.8 86 35 15 24.4 87 35 25 25.9 88 35 35 29.4 89 35 45 28.0 90 35 55 14.1 96 35 115 9.2 97 35 125 10.8 98 35 135 22.2 99 35 145 23.3 100 35 155 21.1 101 35 165 19.9 102 35 175 19.5 103 35 185 20.2 104 35 195 20.1 105 35 205 19.7 106 35 215 21.6 107 35 225 24.4 108 35 235 25.4 109 35 245 22.3 112 35 275 27.2 113 35 285 27.8 114 35 295 31.8 115 35 305 34.2 116 35 315 37.6 117 35 325 35.5 118 35 335 33.5 119 35 345 34.2 120 35 355 26.3 124 25 35 8.1 125 25 45 12.8 126 25 55 10.9 127 25 65 22.7 128 25 75 26.8 129 25 85 37.6 130 25 95 48.1 131 25 105 16.2 132 25 115 24.3 133 25 125 29.8 134 25 135 37.1 135 25 145 46.5 136 25 155 40.4 137 25 165 39.9 138 25 175 42.3 139 25 185 43.5 140 25 195 46.7 141 25 205 47.1 142 25 215 36.9 143 25 225 27.9 144 25 235 27.6 145 25 245 26.0 146 25 255 26.5 147 25 265 27.5 148 25 275 45.1 149 25 285 48.5 150 25 295 54.0 151 25 305 55.0 152 25 315 52.3 153 25 325 49.6 154 25 335 47.5 155 25 345 32.5 156 25 355 30.3 160 15 35 12.8 161 15 45 30.9 162 15 55 53.6 163 15 65 48.4 164 15 75 51.6 165 15 85 59.9 166 15 95 57.5 167 15 105 36.1 168 15 115 63.3 169 15 125 57.4 170 15 135 63.1 171 15 145 60.7 172 15 155 61.9 173 15 165 66.8 174 15 175 57.3 175 15 185 53.6 176 15 195 57.8 177 15 205 52.2 178 15 215 41.0 179 15 225 33.9 180 15 235 30.4 181 15 245 40.7 182 15 255 40.6 183 15 265 39.9 184 15 275 51.7 185 15 285 57.0 186 15 295 62.3 187 15 305 64.0 188 15 315 58.9 189 15 325 51.3 190 15 335 42.9 191 15 345 11.3 193 5 5 44.5 197 5 45 70.2 198 5 55 69.7 199 5 65 71.3 200 5 75 56.8 201 5 85 51.3 202 5 95 46.4 203 5 105 61.7 204 5 115 59.3 205 5 125 54.2 206 5 135 51.6 207 5 145 46.1 208 5 155 41.4 209 5 165 45.6 210 5 175 49.6 211 5 185 44.4 212 5 195 48.5 213 5 205 43.8 214 5 215 35.0 215 5 225 40.0 216 5 235 42.7 217 5 245 47.4 218 5 255 51.6 219 5 265 50.5 220 5 275 36.5 221 5 285 32.2 223 5 305 53.7 224 5 315 42.2 225 5 325 42.9 226 5 335 44.9 227 5 345 32.3 228 5 355 44.6 229 -5 5 46.6 230 -5 15 32.6 232 -5 35 48.4 233 -5 45 61.4 234 -5 55 62.0 235 -5 65 57.9 236 -5 75 55.6 237 -5 85 51.9 238 -5 95 48.8 239 -5 105 45.7 240 -5 115 46.6 241 -5 125 54.8 242 -5 135 51.3 243 -5 145 43.2 244 -5 155 41.5 245 -5 165 42.9 246 -5 175 43.5 247 -5 185 57.1 248 -5 195 59.5 249 -5 205 66.4 250 -5 215 57.4 251 -5 225 63.3 252 -5 235 64.9 253 -5 245 56.8 254 -5 255 54.5 255 -5 265 46.3 256 -5 275 30.0 257 -5 285 22.9 260 -5 315 44.6 261 -5 325 52.0 262 -5 335 53.8 263 -5 345 60.0 264 -5 355 55.6 265 -15 5 27.0 266 -15 15 18.5 268 -15 35 61.4 269 -15 45 55.7 270 -15 55 56.4 271 -15 65 54.0 272 -15 75 55.6 273 -15 85 49.7 274 -15 95 46.2 275 -15 105 58.5 276 -15 115 43.4 277 -15 125 46.4 278 -15 135 51.9 279 -15 145 48.6 280 -15 155 49.3 281 -15 165 50.9 282 -15 175 44.3 283 -15 185 46.3 284 -15 195 52.4 285 -15 205 56.2 286 -15 215 63.9 287 -15 225 66.0 288 -15 235 66.2 289 -15 245 65.0 290 -15 255 56.4 291 -15 265 41.6 292 -15 275 33.4 293 -15 285 23.8 297 -15 325 57.4 298 -15 335 62.4 299 -15 345 60.1 300 -15 355 38.5 301 -25 5 28.1 302 -25 15 23.1 304 -25 35 54.0 305 -25 45 52.8 306 -25 55 51.0 307 -25 65 49.2 308 -25 75 49.8 309 -25 85 43.5 310 -25 95 42.9 311 -25 105 44.9 312 -25 115 35.5 315 -25 145 48.0 316 -25 155 52.4 317 -25 165 51.4 318 -25 175 42.8 319 -25 185 44.5 320 -25 195 40.0 321 -25 205 41.6 322 -25 215 44.3 323 -25 225 50.0 324 -25 235 53.5 325 -25 245 54.5 326 -25 255 48.8 327 -25 265 40.4 328 -25 275 30.2 329 -25 285 18.2 332 -25 315 41.5 333 -25 325 52.0 334 -25 335 46.3 335 -25 345 47.5 336 -25 355 39.0 337 -35 5 22.6 338 -35 15 25.2 339 -35 25 28.7 340 -35 35 41.9 341 -35 45 38.5 342 -35 55 34.9 343 -35 65 29.2 344 -35 75 27.9 345 -35 85 26.1 346 -35 95 22.3 347 -35 105 28.1 348 -35 115 30.1 349 -35 125 24.3 350 -35 135 22.8 351 -35 145 24.2 352 -35 155 36.6 353 -35 165 36.1 354 -35 175 36.6 355 -35 185 36.1 356 -35 195 34.5 357 -35 205 33.0 358 -35 215 28.6 359 -35 225 31.0 360 -35 235 36.7 361 -35 245 28.2 362 -35 255 24.9 363 -35 265 27.0 364 -35 275 30.6 365 -35 285 21.6 367 -35 305 28.6 368 -35 315 39.3 369 -35 325 33.9 370 -35 335 28.8 371 -35 345 29.6 372 -35 355 26.9 373 -45 5 12.3 374 -45 15 12.8 375 -45 25 11.6 376 -45 35 13.8 377 -45 45 13.1 378 -45 55 21.7 379 -45 65 16.3 380 -45 75 13.8 381 -45 85 11.4 382 -45 95 12.7 383 -45 105 12.3 384 -45 115 15.1 385 -45 125 21.1 386 -45 135 17.6 387 -45 145 25.0 388 -45 155 20.8 389 -45 165 19.7 390 -45 175 21.2 391 -45 185 18.8 392 -45 195 18.1 393 -45 205 19.6 394 -45 215 19.0 395 -45 225 11.6 396 -45 235 15.5 397 -45 245 13.2 398 -45 255 15.9 399 -45 265 19.6 400 -45 275 19.2 401 -45 285 17.6 402 -45 295 19.1 403 -45 305 20.0 404 -45 315 24.5 405 -45 325 17.5 406 -45 335 21.7 407 -45 345 27.3 408 -45 355 19.5 409 -55 10 11.7 410 -55 30 6.7 411 -55 50 14.6 412 -55 70 12.0 413 -55 90 6.1 414 -55 110 15.2 415 -55 130 8.2 416 -55 150 16.7 417 -55 170 13.5 418 -55 190 7.2 419 -55 210 11.3 420 -55 230 6.5 421 -55 250 12.2 422 -55 270 16.1 423 -55 290 18.6 424 -55 310 16.1 425 -55 330 12.0 426 -55 350 13.0 427 -65 10 4.6 428 -65 30 8.9 429 -65 50 6.0 430 -65 70 5.7 431 -65 90 4.1 432 -65 110 8.3 433 -65 130 9.2 434 -65 150 5.3 435 -65 170 4.7 438 -65 230 1.3 440 -65 270 4.8 441 -65 290 3.3 442 -65 310 7.7 443 -65 330 8.6 444 -65 350 5.8 450 -75 220 5.2