Cumulus Frequency of Occurrence (%) December, January, February (1954 - 1997) Day, Ship Observations Only Global Average: 35.4 Zonal Averages 17 zones Lat.N Average 85 1.5 75 5.1 65 12.0 55 14.6 45 17.6 35 28.6 25 41.5 15 50.9 5 47.7 -5 54.1 -15 50.6 -25 48.4 -35 34.8 -45 20.7 -55 14.5 -65 8.8 -75 8.4 Grid Box Averages 394 filled boxes Box # Lat.N Lon.E Average 1 85 60 3.2 2 85 180 0.2 3 85 300 1.2 4 75 20 10.4 5 75 60 5.3 6 75 100 6.1 7 75 140 2.9 8 75 180 0.5 9 75 220 0.2 11 75 300 9.2 12 75 340 13.6 13 65 10 12.3 14 65 30 11.4 15 65 50 9.9 21 65 170 8.9 22 65 190 6.5 23 65 210 9.5 27 65 290 15.2 29 65 330 12.5 30 65 350 14.2 31 55 10 14.7 32 55 30 10.6 37 55 130 20.4 38 55 150 14.4 39 55 170 13.3 40 55 190 13.1 41 55 210 12.2 42 55 230 13.8 45 55 290 24.1 46 55 310 17.8 47 55 330 15.4 48 55 350 14.8 49 45 5 27.5 50 45 15 25.5 51 45 25 15.5 52 45 35 15.4 53 45 45 13.1 54 45 55 16.3 61 45 125 25.1 62 45 135 21.5 63 45 145 22.7 64 45 155 15.9 65 45 165 15.5 66 45 175 16.8 67 45 185 17.8 68 45 195 16.3 69 45 205 14.3 70 45 215 13.9 71 45 225 15.1 72 45 235 16.3 77 45 285 20.1 78 45 295 19.5 79 45 305 15.0 80 45 315 17.4 81 45 325 19.7 82 45 335 20.0 83 45 345 19.5 84 45 355 20.3 85 35 5 32.0 86 35 15 35.2 87 35 25 38.0 88 35 35 41.3 89 35 45 21.8 90 35 55 24.6 96 35 115 10.6 97 35 125 23.7 98 35 135 35.5 99 35 145 30.9 100 35 155 25.8 101 35 165 28.8 102 35 175 26.1 103 35 185 26.3 104 35 195 23.6 105 35 205 23.1 106 35 215 22.4 107 35 225 23.1 108 35 235 22.5 109 35 245 20.9 112 35 275 24.5 113 35 285 28.8 114 35 295 28.3 115 35 305 31.2 116 35 315 34.6 117 35 325 32.2 118 35 335 30.6 119 35 345 33.8 120 35 355 29.2 124 25 35 39.5 125 25 45 21.4 126 25 55 32.5 127 25 65 37.5 128 25 75 11.7 129 25 85 24.2 130 25 95 19.2 131 25 105 12.9 132 25 115 21.7 133 25 125 29.1 134 25 135 38.6 135 25 145 45.3 136 25 155 44.1 137 25 165 44.0 138 25 175 43.9 139 25 185 46.0 140 25 195 44.8 141 25 205 45.2 142 25 215 38.0 143 25 225 30.9 144 25 235 29.9 145 25 245 30.2 146 25 255 35.8 147 25 265 29.6 148 25 275 43.0 149 25 285 48.5 150 25 295 53.1 151 25 305 54.6 152 25 315 51.9 153 25 325 49.1 154 25 335 47.1 155 25 345 28.2 156 25 355 33.1 160 15 35 46.7 161 15 45 46.4 162 15 55 59.3 163 15 65 54.5 164 15 75 36.8 165 15 85 50.4 166 15 95 42.4 167 15 105 36.0 168 15 115 48.8 169 15 125 44.2 170 15 135 48.9 171 15 145 55.3 172 15 155 59.2 173 15 165 61.5 174 15 175 56.9 175 15 185 55.9 176 15 195 55.3 177 15 205 53.0 178 15 215 46.2 179 15 225 41.2 180 15 235 38.0 181 15 245 47.6 182 15 255 50.9 183 15 265 41.9 184 15 275 45.6 185 15 285 59.7 186 15 295 63.3 187 15 305 62.2 188 15 315 59.5 189 15 325 53.2 190 15 335 40.9 191 15 345 10.6 193 5 5 41.6 197 5 45 69.4 198 5 55 66.3 199 5 65 67.6 200 5 75 53.3 201 5 85 52.2 202 5 95 49.9 203 5 105 44.5 204 5 115 45.2 205 5 125 46.1 206 5 135 46.0 207 5 145 45.6 208 5 155 47.7 209 5 165 48.3 210 5 175 49.9 211 5 185 49.5 212 5 195 53.3 213 5 205 46.9 214 5 215 42.7 215 5 225 40.9 216 5 235 40.1 217 5 245 43.2 218 5 255 47.4 219 5 265 46.2 220 5 275 42.9 221 5 285 37.2 222 5 295 55.6 223 5 305 53.9 224 5 315 44.1 225 5 325 46.4 226 5 335 44.6 227 5 345 33.6 228 5 355 43.7 229 -5 5 48.9 230 -5 15 34.8 232 -5 35 58.8 233 -5 45 66.4 234 -5 55 58.3 235 -5 65 53.9 236 -5 75 49.0 237 -5 85 49.1 238 -5 95 43.6 239 -5 105 39.7 240 -5 115 38.1 241 -5 125 46.0 242 -5 135 44.6 243 -5 145 40.4 244 -5 155 44.2 245 -5 165 46.5 246 -5 175 44.8 247 -5 185 53.4 248 -5 195 61.2 249 -5 205 68.8 250 -5 215 68.1 251 -5 225 70.4 252 -5 235 71.2 253 -5 245 62.7 254 -5 255 52.0 255 -5 265 48.7 256 -5 275 35.1 257 -5 285 23.6 260 -5 315 52.4 261 -5 325 65.5 262 -5 335 63.0 263 -5 345 61.2 264 -5 355 57.9 265 -15 5 32.9 266 -15 15 19.6 268 -15 35 53.1 269 -15 45 50.5 270 -15 55 57.1 271 -15 65 55.5 272 -15 75 52.5 273 -15 85 56.4 274 -15 95 52.0 275 -15 105 49.0 276 -15 115 44.6 277 -15 125 49.3 278 -15 135 45.8 279 -15 145 47.1 280 -15 155 52.8 281 -15 165 48.8 282 -15 175 48.3 283 -15 185 44.7 284 -15 195 46.3 285 -15 205 49.3 286 -15 215 53.5 287 -15 225 64.2 288 -15 235 67.1 289 -15 245 62.3 290 -15 255 55.1 291 -15 265 46.7 292 -15 275 40.0 293 -15 285 27.8 297 -15 325 61.1 298 -15 335 59.8 299 -15 345 50.9 300 -15 355 40.2 301 -25 5 37.4 302 -25 15 25.8 304 -25 35 52.8 305 -25 45 52.8 306 -25 55 55.7 307 -25 65 56.9 308 -25 75 59.4 309 -25 85 54.0 310 -25 95 45.1 311 -25 105 34.2 312 -25 115 34.3 315 -25 145 53.5 316 -25 155 53.9 317 -25 165 54.4 318 -25 175 50.4 319 -25 185 48.1 320 -25 195 46.0 321 -25 205 43.4 322 -25 215 46.9 323 -25 225 53.1 324 -25 235 58.6 325 -25 245 59.6 326 -25 255 56.3 327 -25 265 49.1 328 -25 275 36.1 329 -25 285 21.0 332 -25 315 40.3 333 -25 325 49.6 334 -25 335 52.8 335 -25 345 55.0 336 -25 355 47.3 337 -35 5 38.6 338 -35 15 33.8 339 -35 25 34.5 340 -35 35 39.8 341 -35 45 38.1 342 -35 55 34.1 343 -35 65 34.3 344 -35 75 34.9 345 -35 85 34.3 346 -35 95 30.4 347 -35 105 27.2 348 -35 115 31.8 349 -35 125 27.6 350 -35 135 28.4 351 -35 145 29.1 352 -35 155 38.7 353 -35 165 39.9 354 -35 175 40.4 355 -35 185 43.9 356 -35 195 34.8 357 -35 205 34.2 358 -35 215 32.9 359 -35 225 32.3 360 -35 235 37.3 361 -35 245 37.6 362 -35 255 34.0 363 -35 265 31.1 364 -35 275 30.3 365 -35 285 25.3 366 -35 295 23.2 367 -35 305 33.6 368 -35 315 40.3 369 -35 325 34.4 370 -35 335 33.4 371 -35 345 36.0 372 -35 355 37.4 373 -45 5 14.6 374 -45 15 17.6 375 -45 25 18.3 376 -45 35 18.4 377 -45 45 17.9 378 -45 55 19.3 379 -45 65 18.9 380 -45 75 20.9 381 -45 85 20.9 382 -45 95 19.9 383 -45 105 20.4 384 -45 115 23.0 385 -45 125 21.7 386 -45 135 21.5 387 -45 145 26.5 388 -45 155 25.7 389 -45 165 24.3 390 -45 175 27.4 391 -45 185 25.1 392 -45 195 22.0 393 -45 205 20.6 394 -45 215 17.4 395 -45 225 20.9 396 -45 235 18.6 397 -45 245 15.2 398 -45 255 18.0 399 -45 265 21.4 400 -45 275 26.1 401 -45 285 21.4 402 -45 295 20.5 403 -45 305 21.5 404 -45 315 26.5 405 -45 325 20.8 406 -45 335 17.2 407 -45 345 21.5 408 -45 355 17.0 409 -55 10 11.9 410 -55 30 12.9 411 -55 50 14.0 412 -55 70 14.3 413 -55 90 13.6 414 -55 110 16.8 415 -55 130 15.3 416 -55 150 12.3 417 -55 170 17.2 418 -55 190 11.0 419 -55 210 14.2 420 -55 230 12.8 421 -55 250 16.9 422 -55 270 18.4 423 -55 290 18.9 424 -55 310 14.9 425 -55 330 12.4 426 -55 350 14.6 427 -65 10 11.4 428 -65 30 9.8 429 -65 50 10.3 430 -65 70 13.7 431 -65 90 9.7 432 -65 110 7.4 433 -65 130 7.2 434 -65 150 7.1 435 -65 170 8.7 436 -65 190 8.9 437 -65 210 7.5 438 -65 230 9.7 439 -65 250 10.5 440 -65 270 8.0 441 -65 290 7.3 442 -65 310 7.1 443 -65 330 5.9 444 -65 350 7.7 449 -75 180 14.8 450 -75 220 3.5 451 -75 260 4.6 452 -75 300 7.9 453 -75 340 8.1