Cumulus Frequency of Occurrence (%) May (1954 - 1997) Night, Ship Observations Only Global Average: 32.3 Zonal Averages 16 zones Lat.N Average 85 2.0 75 4.6 65 10.7 55 10.0 45 11.7 35 23.0 25 40.7 15 48.6 5 42.9 -5 53.1 -15 47.6 -25 39.9 -35 28.7 -45 20.2 -55 15.5 -65 4.5 Grid Box Averages 323 filled boxes Box # Lat.N Lon.E Average 1 85 60 4.9 2 85 180 0.4 3 85 300 0.5 4 75 20 11.1 5 75 60 5.7 6 75 100 2.4 7 75 140 2.8 8 75 180 0.9 9 75 220 0.7 11 75 300 9.3 12 75 340 6.8 13 65 10 12.2 14 65 30 10.4 15 65 50 11.4 20 65 150 12.5 21 65 170 7.8 22 65 190 5.5 23 65 210 12.1 28 65 310 6.8 29 65 330 12.8 30 65 350 13.7 31 55 10 12.4 32 55 30 10.0 37 55 130 9.7 38 55 150 7.0 39 55 170 6.2 40 55 190 7.9 41 55 210 10.7 42 55 230 13.5 46 55 310 9.7 47 55 330 12.3 48 55 350 14.3 49 45 5 18.4 50 45 15 18.5 51 45 25 13.2 52 45 35 14.6 53 45 45 9.4 54 45 55 13.3 62 45 135 7.9 63 45 145 8.4 64 45 155 6.0 65 45 165 4.4 66 45 175 5.5 67 45 185 7.1 68 45 195 9.1 69 45 205 10.0 70 45 215 10.0 71 45 225 12.3 72 45 235 18.1 77 45 285 6.8 78 45 295 8.7 79 45 305 8.9 80 45 315 13.9 81 45 325 19.0 82 45 335 18.1 83 45 345 20.0 84 45 355 22.2 85 35 5 19.3 86 35 15 16.9 87 35 25 18.4 88 35 35 27.4 97 35 125 10.4 98 35 135 22.3 99 35 145 19.9 100 35 155 15.3 101 35 165 15.3 102 35 175 17.7 103 35 185 17.5 104 35 195 19.0 105 35 205 18.4 106 35 215 19.8 107 35 225 20.5 108 35 235 18.3 109 35 245 14.6 112 35 275 30.1 113 35 285 28.1 114 35 295 31.9 115 35 305 33.7 116 35 315 38.6 117 35 325 35.9 118 35 335 28.4 119 35 345 29.8 120 35 355 23.6 124 25 35 6.3 125 25 45 5.5 126 25 55 6.4 127 25 65 34.5 129 25 85 34.0 132 25 115 32.4 133 25 125 30.7 134 25 135 34.7 135 25 145 42.5 136 25 155 40.7 137 25 165 43.8 138 25 175 43.8 139 25 185 48.3 140 25 195 52.9 141 25 205 51.1 142 25 215 38.5 143 25 225 22.9 144 25 235 17.2 145 25 245 21.0 146 25 255 29.4 147 25 265 42.5 148 25 275 50.1 149 25 285 46.2 150 25 295 50.9 151 25 305 54.0 152 25 315 55.7 153 25 325 52.0 154 25 335 43.9 155 25 345 29.2 160 15 35 12.0 161 15 45 23.8 162 15 55 48.6 163 15 65 62.2 164 15 75 57.0 165 15 85 46.5 166 15 95 50.5 167 15 105 35.4 168 15 115 56.0 169 15 125 52.7 170 15 135 61.2 171 15 145 61.4 172 15 155 62.6 173 15 165 62.5 174 15 175 56.8 175 15 185 52.0 176 15 195 50.5 177 15 205 56.7 178 15 215 36.7 179 15 225 30.7 180 15 235 21.4 181 15 245 31.4 182 15 255 41.9 183 15 265 38.0 184 15 275 47.4 185 15 285 48.5 186 15 295 54.9 187 15 305 60.5 188 15 315 54.4 189 15 325 44.5 190 15 335 40.8 191 15 345 12.7 193 5 5 38.5 197 5 45 58.5 198 5 55 57.5 199 5 65 57.7 200 5 75 47.4 201 5 85 44.6 202 5 95 38.8 203 5 105 51.1 204 5 115 50.1 205 5 125 43.1 206 5 135 46.2 207 5 145 37.9 208 5 155 40.2 209 5 165 44.2 210 5 175 40.6 211 5 185 48.7 212 5 195 40.2 213 5 205 44.6 214 5 215 46.6 215 5 225 41.5 216 5 235 48.4 217 5 245 34.9 218 5 255 40.0 219 5 265 34.9 220 5 275 29.6 221 5 285 28.7 223 5 305 44.1 224 5 315 39.3 225 5 325 42.1 226 5 335 42.0 227 5 345 33.4 228 5 355 37.7 229 -5 5 40.9 230 -5 15 26.7 233 -5 45 56.5 234 -5 55 61.1 235 -5 65 61.3 236 -5 75 51.4 237 -5 85 50.6 238 -5 95 47.8 239 -5 105 50.5 240 -5 115 52.7 241 -5 125 45.9 242 -5 135 48.9 243 -5 145 39.8 244 -5 155 38.2 245 -5 165 54.2 246 -5 175 53.3 247 -5 185 59.3 248 -5 195 57.2 249 -5 205 66.8 250 -5 215 69.5 251 -5 225 59.1 252 -5 235 63.2 253 -5 245 65.7 254 -5 255 49.5 255 -5 265 39.6 256 -5 275 23.6 260 -5 315 48.0 261 -5 325 48.9 262 -5 335 62.4 263 -5 345 62.7 264 -5 355 48.7 265 -15 5 23.9 266 -15 15 14.9 268 -15 35 57.2 269 -15 45 56.4 270 -15 55 55.7 271 -15 65 52.6 272 -15 75 54.1 273 -15 85 47.6 274 -15 95 44.6 275 -15 105 56.0 276 -15 115 43.1 277 -15 125 33.9 278 -15 135 55.4 279 -15 145 44.4 280 -15 155 48.5 281 -15 165 44.2 282 -15 175 43.0 283 -15 185 45.9 284 -15 195 45.2 285 -15 205 55.0 286 -15 215 60.4 287 -15 225 59.8 288 -15 235 62.4 289 -15 245 62.0 290 -15 255 53.1 291 -15 265 36.6 292 -15 275 22.0 293 -15 285 15.5 297 -15 325 56.5 298 -15 335 60.5 299 -15 345 52.8 300 -15 355 31.5 301 -25 5 26.5 302 -25 15 23.2 304 -25 35 50.1 305 -25 45 48.9 306 -25 55 50.9 307 -25 65 47.5 308 -25 75 40.4 309 -25 85 36.1 310 -25 95 35.9 311 -25 105 43.0 312 -25 115 32.0 316 -25 155 45.2 317 -25 165 47.5 318 -25 175 41.7 319 -25 185 36.9 320 -25 195 41.5 321 -25 205 44.3 322 -25 215 38.6 323 -25 225 42.0 324 -25 235 49.5 325 -25 245 51.9 326 -25 255 44.9 327 -25 265 26.8 328 -25 275 28.1 329 -25 285 20.0 332 -25 315 37.2 333 -25 325 43.8 334 -25 335 39.8 335 -25 345 38.6 336 -25 355 36.1 337 -35 5 24.9 338 -35 15 26.3 339 -35 25 22.4 340 -35 35 39.5 341 -35 45 34.9 342 -35 55 33.9 343 -35 65 27.8 344 -35 75 25.3 345 -35 85 20.9 346 -35 95 16.9 347 -35 105 27.8 348 -35 115 28.1 349 -35 125 25.7 350 -35 135 24.7 351 -35 145 25.5 352 -35 155 33.0 353 -35 165 31.1 354 -35 175 33.1 355 -35 185 31.7 356 -35 195 34.2 357 -35 205 33.1 358 -35 215 28.0 359 -35 225 26.0 360 -35 235 21.5 364 -35 275 25.8 365 -35 285 16.4 367 -35 305 23.9 368 -35 315 34.5 369 -35 325 38.6 370 -35 335 40.1 371 -35 345 26.0 372 -35 355 24.1 387 -45 145 27.1 388 -45 155 22.4 389 -45 165 19.2 390 -45 175 17.7 391 -45 185 14.4 392 -45 195 19.6 393 -45 205 17.0 397 -45 245 17.8 398 -45 255 17.3 399 -45 265 25.2 400 -45 275 21.5 401 -45 285 19.8 402 -45 295 11.8 403 -45 305 19.6 404 -45 315 26.1 405 -45 325 22.7 417 -55 170 16.0 422 -55 270 17.5 423 -55 290 14.6 424 -55 310 9.4 425 -55 330 19.9 442 -65 310 4.5