Cumulus Frequency of Occurrence (%) April (1954 - 1997) Day, Ship Observations Only Global Average: 35.7 Zonal Averages 17 zones Lat.N Average 85 4.2 75 6.2 65 15.3 55 15.8 45 17.6 35 27.8 25 42.7 15 54.0 5 50.6 -5 55.3 -15 53.6 -25 46.5 -35 32.1 -45 18.4 -55 13.5 -65 6.5 -75 6.1 Grid Box Averages 377 filled boxes Box # Lat.N Lon.E Average 1 85 60 9.0 2 85 180 1.0 3 85 300 2.1 4 75 20 15.1 5 75 60 9.3 6 75 100 8.6 7 75 140 2.5 8 75 180 1.4 9 75 220 0.0 11 75 300 6.1 12 75 340 9.1 13 65 10 17.0 14 65 30 13.5 15 65 50 11.0 21 65 170 11.8 22 65 190 9.9 23 65 210 15.3 29 65 330 16.4 30 65 350 18.5 31 55 10 16.5 32 55 30 12.2 38 55 150 13.2 39 55 170 14.1 40 55 190 13.2 41 55 210 16.3 42 55 230 19.6 46 55 310 17.3 47 55 330 16.8 48 55 350 17.9 49 45 5 25.1 50 45 15 23.1 51 45 25 15.2 52 45 35 14.0 53 45 45 12.4 54 45 55 9.0 62 45 135 12.0 63 45 145 13.5 64 45 155 11.7 65 45 165 11.4 66 45 175 13.2 67 45 185 14.2 68 45 195 14.0 69 45 205 16.2 70 45 215 17.8 71 45 225 20.5 72 45 235 24.3 77 45 285 11.1 78 45 295 14.2 79 45 305 14.7 80 45 315 17.7 81 45 325 24.0 82 45 335 24.6 83 45 345 26.7 84 45 355 26.6 85 35 5 25.6 86 35 15 27.1 87 35 25 29.3 88 35 35 32.6 89 35 45 29.3 90 35 55 15.0 96 35 115 9.2 97 35 125 9.9 98 35 135 22.6 99 35 145 24.2 100 35 155 23.0 101 35 165 22.7 102 35 175 22.5 103 35 185 22.3 104 35 195 22.1 105 35 205 21.9 106 35 215 24.0 107 35 225 26.7 108 35 235 27.4 109 35 245 24.1 112 35 275 29.7 113 35 285 30.0 114 35 295 35.0 115 35 305 36.0 116 35 315 38.9 117 35 325 38.3 118 35 335 35.9 119 35 345 38.4 120 35 355 29.1 124 25 35 9.4 125 25 45 13.7 126 25 55 12.4 127 25 65 23.4 128 25 75 27.4 129 25 85 42.0 130 25 95 49.1 131 25 105 18.2 132 25 115 24.5 133 25 125 31.8 134 25 135 39.1 135 25 145 48.4 136 25 155 42.5 137 25 165 45.6 138 25 175 46.4 139 25 185 46.5 140 25 195 49.3 141 25 205 49.9 142 25 215 40.0 143 25 225 30.8 144 25 235 30.4 145 25 245 27.6 146 25 255 27.1 147 25 265 28.2 148 25 275 44.5 149 25 285 52.7 150 25 295 55.5 151 25 305 56.2 152 25 315 55.0 153 25 325 53.1 154 25 335 50.9 155 25 345 35.0 160 15 35 14.6 161 15 45 33.5 162 15 55 56.4 163 15 65 49.9 164 15 75 53.1 165 15 85 60.1 166 15 95 56.8 167 15 105 38.8 168 15 115 65.5 169 15 125 60.8 170 15 135 65.9 171 15 145 63.9 172 15 155 64.0 173 15 165 70.3 174 15 175 59.8 175 15 185 56.1 176 15 195 60.3 177 15 205 55.1 178 15 215 43.3 179 15 225 35.7 180 15 235 34.7 181 15 245 44.1 182 15 255 42.1 183 15 265 39.5 184 15 275 51.7 185 15 285 59.3 186 15 295 63.8 187 15 305 64.4 188 15 315 60.8 189 15 325 53.6 190 15 335 45.1 191 15 345 12.1 193 5 5 46.7 197 5 45 71.5 198 5 55 71.1 199 5 65 73.0 200 5 75 61.3 201 5 85 54.0 202 5 95 48.2 203 5 105 63.3 204 5 115 62.3 205 5 125 55.3 206 5 135 53.6 207 5 145 47.2 208 5 155 45.4 209 5 165 45.8 210 5 175 51.0 211 5 185 45.7 212 5 195 50.0 213 5 205 47.2 214 5 215 41.7 215 5 225 44.7 216 5 235 46.2 217 5 245 50.0 218 5 255 55.5 219 5 265 53.8 220 5 275 38.5 221 5 285 34.0 223 5 305 54.4 224 5 315 44.3 225 5 325 43.7 226 5 335 46.6 227 5 345 34.0 228 5 355 48.1 229 -5 5 48.6 230 -5 15 31.6 232 -5 35 48.2 233 -5 45 62.7 234 -5 55 63.8 235 -5 65 60.9 236 -5 75 56.0 237 -5 85 53.0 238 -5 95 49.5 239 -5 105 47.1 240 -5 115 47.7 241 -5 125 56.5 242 -5 135 52.8 243 -5 145 43.5 244 -5 155 45.0 245 -5 165 44.9 246 -5 175 47.5 247 -5 185 57.7 248 -5 195 60.9 249 -5 205 64.8 250 -5 215 65.9 251 -5 225 66.8 252 -5 235 67.1 253 -5 245 60.5 254 -5 255 56.3 255 -5 265 51.9 256 -5 275 34.0 257 -5 285 21.3 260 -5 315 47.1 261 -5 325 52.7 262 -5 335 56.0 263 -5 345 61.7 264 -5 355 60.5 265 -15 5 33.1 266 -15 15 18.7 268 -15 35 62.6 269 -15 45 58.0 270 -15 55 59.1 271 -15 65 56.9 272 -15 75 56.9 273 -15 85 53.3 274 -15 95 49.2 275 -15 105 59.0 276 -15 115 46.7 277 -15 125 53.4 278 -15 135 53.8 279 -15 145 47.9 280 -15 155 50.1 281 -15 165 50.7 282 -15 175 47.3 283 -15 185 47.4 284 -15 195 53.4 285 -15 205 55.8 286 -15 215 64.1 287 -15 225 68.0 288 -15 235 69.1 289 -15 245 65.8 290 -15 255 58.5 291 -15 265 49.8 292 -15 275 37.7 293 -15 285 25.8 297 -15 325 58.7 298 -15 335 65.3 299 -15 345 63.3 300 -15 355 45.9 301 -25 5 34.0 302 -25 15 24.9 304 -25 35 56.9 305 -25 45 55.2 306 -25 55 53.4 307 -25 65 53.6 308 -25 75 49.8 309 -25 85 49.6 310 -25 95 47.8 311 -25 105 44.3 312 -25 115 37.8 315 -25 145 50.4 316 -25 155 55.6 317 -25 165 52.9 318 -25 175 45.8 319 -25 185 45.8 320 -25 195 39.9 321 -25 205 40.1 322 -25 215 45.0 323 -25 225 49.6 324 -25 235 56.0 325 -25 245 55.9 326 -25 255 53.5 327 -25 265 43.9 328 -25 275 34.7 329 -25 285 18.6 332 -25 315 42.6 333 -25 325 53.6 334 -25 335 49.9 335 -25 345 48.1 336 -25 355 44.6 337 -35 5 26.4 338 -35 15 28.0 339 -35 25 31.1 340 -35 35 44.7 341 -35 45 40.0 342 -35 55 35.7 343 -35 65 31.4 344 -35 75 30.3 345 -35 85 29.1 346 -35 95 27.2 347 -35 105 25.9 348 -35 115 30.9 349 -35 125 25.4 350 -35 135 24.0 351 -35 145 25.6 352 -35 155 39.0 353 -35 165 38.0 354 -35 175 38.8 355 -35 185 39.0 356 -35 195 32.8 357 -35 205 33.2 358 -35 215 29.5 359 -35 225 31.2 360 -35 235 35.6 361 -35 245 29.4 362 -35 255 22.1 363 -35 265 31.4 364 -35 275 32.6 365 -35 285 22.9 367 -35 305 30.1 368 -35 315 40.5 369 -35 325 35.2 370 -35 335 32.2 371 -35 345 30.6 372 -35 355 29.6 373 -45 5 16.9 374 -45 15 11.9 375 -45 25 14.7 376 -45 35 11.6 377 -45 45 15.0 378 -45 55 23.2 379 -45 65 13.3 380 -45 75 18.4 381 -45 85 11.6 382 -45 95 13.1 383 -45 105 12.2 384 -45 115 15.6 385 -45 125 20.9 386 -45 135 17.1 387 -45 145 27.1 388 -45 155 19.9 389 -45 165 20.5 390 -45 175 24.7 391 -45 185 21.1 392 -45 195 16.7 393 -45 205 15.4 394 -45 215 17.9 395 -45 225 11.7 396 -45 235 14.3 397 -45 245 17.9 398 -45 255 24.8 399 -45 265 19.2 400 -45 275 19.5 401 -45 285 15.6 402 -45 295 19.0 403 -45 305 21.8 404 -45 315 26.8 405 -45 325 20.6 406 -45 335 21.7 407 -45 345 26.4 408 -45 355 23.3 409 -55 10 13.6 410 -55 30 6.6 411 -55 50 14.4 412 -55 70 13.8 413 -55 90 9.5 414 -55 110 15.0 416 -55 150 17.0 417 -55 170 14.9 419 -55 210 12.6 420 -55 230 8.3 421 -55 250 10.9 422 -55 270 18.6 423 -55 290 20.2 424 -55 310 15.5 425 -55 330 13.8 426 -55 350 13.2 427 -65 10 5.3 428 -65 30 6.5 429 -65 50 8.1 430 -65 70 8.9 431 -65 90 4.9 432 -65 110 9.3 433 -65 130 7.3 434 -65 150 6.1 435 -65 170 4.3 440 -65 270 6.3 441 -65 290 2.1 442 -65 310 9.1 443 -65 330 8.6 444 -65 350 5.8 450 -75 220 6.1