Cumulus Frequency of Occurrence (%) May (1954 - 1997) Day, Ship Observations Only Global Average: 35.4 Zonal Averages 16 zones Lat.N Average 85 2.1 75 5.1 65 14.9 55 13.5 45 15.6 35 27.7 25 46.0 15 52.5 5 47.2 -5 57.4 -15 52.2 -25 44.2 -35 30.7 -45 19.7 -55 13.8 -65 8.5 Grid Box Averages 359 filled boxes Box # Lat.N Lon.E Average 1 85 60 4.8 2 85 180 0.8 3 85 300 0.4 4 75 20 12.6 5 75 60 8.0 6 75 100 4.7 7 75 140 0.5 8 75 180 1.3 9 75 220 0.4 11 75 300 7.3 12 75 340 8.7 13 65 10 15.9 14 65 30 12.4 15 65 50 12.4 20 65 150 17.2 21 65 170 11.0 22 65 190 7.3 23 65 210 21.3 27 65 290 18.9 29 65 330 16.5 30 65 350 17.2 31 55 10 15.6 32 55 30 12.8 37 55 130 9.2 38 55 150 9.6 39 55 170 8.6 40 55 190 9.4 41 55 210 13.7 42 55 230 19.5 45 55 290 29.4 46 55 310 11.7 47 55 330 17.0 48 55 350 19.0 49 45 5 23.1 50 45 15 24.8 51 45 25 20.4 52 45 35 14.2 53 45 45 15.7 54 45 55 11.9 62 45 135 11.1 63 45 145 10.7 64 45 155 7.4 65 45 165 6.6 66 45 175 7.8 67 45 185 10.1 68 45 195 11.5 69 45 205 13.7 70 45 215 14.4 71 45 225 18.7 72 45 235 22.9 77 45 285 10.5 78 45 295 12.1 79 45 305 13.1 80 45 315 17.0 81 45 325 25.1 82 45 335 25.1 83 45 345 27.3 84 45 355 27.0 85 35 5 21.9 86 35 15 20.6 87 35 25 23.8 88 35 35 31.3 90 35 55 16.3 96 35 115 11.3 97 35 125 9.0 98 35 135 21.9 99 35 145 22.0 100 35 155 19.9 101 35 165 19.1 102 35 175 22.4 103 35 185 22.5 104 35 195 21.6 105 35 205 23.5 106 35 215 25.3 107 35 225 25.1 108 35 235 23.2 109 35 245 18.1 112 35 275 33.8 113 35 285 30.9 114 35 295 37.8 115 35 305 39.9 116 35 315 43.6 117 35 325 42.4 118 35 335 37.9 119 35 345 40.5 120 35 355 28.2 124 25 35 7.8 125 25 45 5.7 126 25 55 9.0 127 25 65 36.9 128 25 75 41.0 129 25 85 41.6 130 25 95 51.5 131 25 105 33.3 132 25 115 33.6 133 25 125 34.3 134 25 135 37.1 135 25 145 48.4 136 25 155 50.2 137 25 165 52.6 138 25 175 54.0 139 25 185 54.1 140 25 195 57.0 141 25 205 55.5 142 25 215 44.4 143 25 225 29.9 144 25 235 25.1 145 25 245 24.9 146 25 255 29.4 147 25 265 42.9 148 25 275 50.0 149 25 285 52.3 150 25 295 55.1 151 25 305 59.9 152 25 315 59.7 153 25 325 56.9 154 25 335 52.3 155 25 345 33.0 160 15 35 13.2 161 15 45 30.0 162 15 55 55.1 163 15 65 64.4 164 15 75 59.6 165 15 85 49.1 166 15 95 51.5 167 15 105 42.8 168 15 115 60.5 169 15 125 57.8 170 15 135 61.8 171 15 145 63.3 172 15 155 61.0 173 15 165 71.3 174 15 175 62.7 175 15 185 58.6 176 15 195 58.3 177 15 205 53.6 178 15 215 46.5 179 15 225 35.0 180 15 235 26.6 181 15 245 40.0 182 15 255 44.0 183 15 265 41.3 184 15 275 48.4 185 15 285 54.0 186 15 295 58.3 187 15 305 61.5 188 15 315 57.5 189 15 325 48.1 190 15 335 43.7 191 15 345 14.5 193 5 5 39.8 197 5 45 64.3 198 5 55 60.2 199 5 65 61.6 200 5 75 51.9 201 5 85 48.1 202 5 95 43.4 203 5 105 55.7 204 5 115 53.5 205 5 125 50.8 206 5 135 49.0 207 5 145 45.1 208 5 155 46.8 209 5 165 46.8 210 5 175 42.4 211 5 185 50.5 212 5 195 50.4 213 5 205 48.2 214 5 215 45.1 215 5 225 45.2 216 5 235 48.2 217 5 245 41.9 218 5 255 45.3 219 5 265 42.4 220 5 275 34.5 221 5 285 32.9 223 5 305 50.1 224 5 315 43.8 225 5 325 46.7 226 5 335 43.7 227 5 345 38.7 228 5 355 43.3 229 -5 5 49.7 230 -5 15 31.9 232 -5 35 45.2 233 -5 45 57.1 234 -5 55 61.7 235 -5 65 59.7 236 -5 75 57.5 237 -5 85 54.6 238 -5 95 51.1 239 -5 105 51.3 240 -5 115 54.0 241 -5 125 55.9 242 -5 135 55.6 243 -5 145 48.5 244 -5 155 43.1 245 -5 165 53.3 246 -5 175 54.5 247 -5 185 57.5 248 -5 195 62.2 249 -5 205 64.6 250 -5 215 66.3 251 -5 225 69.4 252 -5 235 71.0 253 -5 245 70.0 254 -5 255 64.2 255 -5 265 53.2 256 -5 275 31.4 257 -5 285 21.0 260 -5 315 48.0 261 -5 325 53.9 262 -5 335 60.2 263 -5 345 66.2 264 -5 355 59.6 265 -15 5 35.0 266 -15 15 17.5 268 -15 35 66.3 269 -15 45 64.8 270 -15 55 57.9 271 -15 65 56.7 272 -15 75 60.4 273 -15 85 50.3 274 -15 95 46.9 275 -15 105 56.4 276 -15 115 47.2 277 -15 125 51.6 278 -15 135 59.6 279 -15 145 49.7 280 -15 155 50.7 281 -15 165 45.9 282 -15 175 51.5 283 -15 185 49.2 284 -15 195 49.7 285 -15 205 56.6 286 -15 215 63.7 287 -15 225 65.4 288 -15 235 66.3 289 -15 245 62.3 290 -15 255 58.4 291 -15 265 40.7 292 -15 275 27.8 293 -15 285 13.9 297 -15 325 60.2 298 -15 335 63.8 299 -15 345 59.8 300 -15 355 43.9 301 -25 5 36.1 302 -25 15 24.2 304 -25 35 56.0 305 -25 45 54.9 306 -25 55 54.9 307 -25 65 49.0 308 -25 75 45.7 309 -25 85 44.7 310 -25 95 48.6 311 -25 105 43.9 312 -25 115 36.5 315 -25 145 50.0 316 -25 155 50.9 317 -25 165 50.5 318 -25 175 45.3 319 -25 185 47.1 320 -25 195 40.3 321 -25 205 39.8 322 -25 215 41.2 323 -25 225 46.6 324 -25 235 53.2 325 -25 245 50.9 326 -25 255 43.0 327 -25 265 37.8 328 -25 275 33.4 329 -25 285 19.4 332 -25 315 40.8 333 -25 325 52.1 334 -25 335 44.2 335 -25 345 45.0 336 -25 355 39.4 337 -35 5 30.8 338 -35 15 28.5 339 -35 25 28.8 340 -35 35 39.7 341 -35 45 37.6 342 -35 55 30.7 343 -35 65 27.5 344 -35 75 26.5 345 -35 85 22.5 346 -35 95 25.4 347 -35 105 25.6 348 -35 115 30.4 349 -35 125 26.2 350 -35 135 25.5 351 -35 145 24.4 352 -35 155 37.6 353 -35 165 32.2 354 -35 175 36.1 355 -35 185 36.0 356 -35 195 30.8 357 -35 205 31.2 358 -35 215 29.2 359 -35 225 30.2 360 -35 235 33.7 361 -35 245 37.0 362 -35 255 32.6 363 -35 265 26.1 364 -35 275 32.3 365 -35 285 21.8 367 -35 305 26.1 368 -35 315 34.1 369 -35 325 35.2 370 -35 335 30.5 371 -35 345 32.6 372 -35 355 26.7 374 -45 15 17.9 375 -45 25 19.2 376 -45 35 21.0 377 -45 45 10.1 378 -45 55 11.9 379 -45 65 16.2 380 -45 75 18.5 383 -45 105 14.5 384 -45 115 17.7 385 -45 125 17.4 386 -45 135 20.6 387 -45 145 27.4 388 -45 155 19.2 389 -45 165 17.5 390 -45 175 23.9 391 -45 185 22.9 392 -45 195 18.1 393 -45 205 18.3 394 -45 215 16.9 395 -45 225 26.0 396 -45 235 28.5 397 -45 245 19.6 398 -45 255 21.3 399 -45 265 15.5 400 -45 275 22.2 401 -45 285 18.6 402 -45 295 18.4 403 -45 305 21.1 404 -45 315 20.1 405 -45 325 18.1 406 -45 335 22.6 407 -45 345 26.1 408 -45 355 22.1 409 -55 10 7.7 410 -55 30 11.9 411 -55 50 13.0 412 -55 70 10.9 417 -55 170 16.0 419 -55 210 11.9 420 -55 230 17.7 421 -55 250 19.3 422 -55 270 14.3 423 -55 290 15.7 424 -55 310 11.8 425 -55 330 15.8 442 -65 310 8.5