Cumulus Frequency of Occurrence (%) August (1954 - 1997) Night, Ship Observations Only Global Average: 32.2 Zonal Averages 15 zones Lat.N Average 85 1.6 75 4.1 65 8.8 55 9.2 45 13.7 35 37.4 25 45.6 15 41.7 5 41.2 -5 47.4 -15 39.6 -25 34.3 -35 27.5 -45 21.3 -55 14.7 Grid Box Averages 319 filled boxes Box # Lat.N Lon.E Average 1 85 60 2.7 2 85 180 0.5 3 85 300 1.8 4 75 20 8.2 5 75 60 6.9 6 75 100 2.2 7 75 140 3.5 8 75 180 1.8 9 75 220 1.3 10 75 260 3.8 11 75 300 5.2 12 75 340 3.9 13 65 10 13.5 14 65 30 11.3 15 65 50 11.0 16 65 70 7.6 21 65 170 8.8 22 65 190 6.5 23 65 210 8.8 24 65 230 6.7 25 65 250 8.5 26 65 270 7.9 27 65 290 5.6 28 65 310 4.2 29 65 330 9.1 30 65 350 10.9 31 55 10 18.8 32 55 30 22.1 37 55 130 5.7 38 55 150 7.7 39 55 170 6.3 40 55 190 4.5 41 55 210 7.9 42 55 230 13.7 44 55 270 8.0 45 55 290 10.5 46 55 310 7.6 47 55 330 10.5 48 55 350 14.1 49 45 5 20.2 50 45 15 17.1 51 45 25 21.7 52 45 35 20.4 54 45 55 12.8 62 45 135 14.9 63 45 145 9.4 64 45 155 6.1 65 45 165 4.7 66 45 175 5.0 67 45 185 6.9 68 45 195 8.3 69 45 205 8.3 70 45 215 9.5 71 45 225 15.1 72 45 235 15.6 77 45 285 15.0 78 45 295 13.1 79 45 305 18.1 80 45 315 21.0 81 45 325 25.2 82 45 335 20.8 83 45 345 22.0 84 45 355 23.3 85 35 5 27.8 86 35 15 20.2 87 35 25 14.3 88 35 35 30.8 97 35 125 34.1 98 35 135 41.4 99 35 145 34.8 100 35 155 33.8 101 35 165 40.6 102 35 175 38.0 103 35 185 40.4 104 35 195 40.9 105 35 205 36.1 106 35 215 31.2 107 35 225 23.8 108 35 235 14.7 109 35 245 11.7 112 35 275 43.8 113 35 285 37.6 114 35 295 44.7 115 35 305 55.7 116 35 315 62.1 117 35 325 55.0 118 35 335 42.7 119 35 345 35.1 120 35 355 20.0 124 25 35 4.5 125 25 45 2.7 126 25 55 9.8 127 25 65 20.0 129 25 85 24.3 132 25 115 41.1 133 25 125 48.9 134 25 135 48.2 135 25 145 45.4 136 25 155 50.5 137 25 165 49.9 138 25 175 50.9 139 25 185 56.6 140 25 195 58.6 141 25 205 54.7 142 25 215 37.9 143 25 225 20.6 144 25 235 13.1 145 25 245 26.0 146 25 255 42.8 147 25 265 50.9 148 25 275 52.6 149 25 285 50.5 150 25 295 59.9 151 25 305 66.0 152 25 315 62.4 153 25 325 57.4 154 25 335 41.1 155 25 345 21.3 160 15 35 9.9 161 15 45 9.3 162 15 55 17.4 163 15 65 36.3 164 15 75 31.0 165 15 85 33.0 166 15 95 28.0 167 15 105 37.1 168 15 115 42.4 169 15 125 36.8 170 15 135 33.4 171 15 145 36.8 172 15 155 46.7 173 15 165 53.1 174 15 175 55.6 175 15 185 59.2 176 15 195 57.8 177 15 205 49.7 178 15 215 37.6 179 15 225 34.5 180 15 235 30.6 181 15 245 41.2 182 15 255 36.0 183 15 265 32.0 184 15 275 44.8 185 15 285 50.5 186 15 295 55.7 187 15 305 58.1 188 15 315 48.2 189 15 325 40.2 190 15 335 36.9 191 15 345 31.0 193 5 5 26.1 197 5 45 53.2 198 5 55 45.2 199 5 65 58.6 200 5 75 45.0 201 5 85 45.9 202 5 95 38.1 203 5 105 40.0 204 5 115 38.9 205 5 125 41.3 206 5 135 38.6 207 5 145 39.7 208 5 155 41.9 209 5 165 39.1 210 5 175 52.9 211 5 185 46.0 212 5 195 54.5 213 5 205 47.3 214 5 215 41.6 215 5 225 38.5 216 5 235 47.0 217 5 245 31.7 218 5 255 26.9 219 5 265 20.0 220 5 275 23.1 221 5 285 27.1 223 5 305 51.3 224 5 315 49.2 225 5 325 56.5 226 5 335 45.0 227 5 345 29.0 228 5 355 23.8 229 -5 5 19.5 230 -5 15 15.1 233 -5 45 58.1 234 -5 55 50.2 235 -5 65 49.5 236 -5 75 49.2 237 -5 85 45.4 238 -5 95 44.4 239 -5 105 49.9 240 -5 115 53.5 241 -5 125 47.6 242 -5 135 49.9 243 -5 145 42.9 244 -5 155 37.1 245 -5 165 50.3 246 -5 175 54.3 247 -5 185 59.2 248 -5 195 61.6 249 -5 205 66.7 250 -5 215 65.7 251 -5 225 66.0 252 -5 235 63.4 253 -5 245 55.7 254 -5 255 32.1 255 -5 265 11.2 256 -5 275 9.9 260 -5 315 53.4 261 -5 325 60.1 262 -5 335 57.5 263 -5 345 43.5 264 -5 355 25.9 265 -15 5 7.5 266 -15 15 14.3 268 -15 35 49.3 269 -15 45 46.9 270 -15 55 51.9 271 -15 65 47.7 272 -15 75 40.4 273 -15 85 38.7 274 -15 95 38.5 275 -15 105 49.2 276 -15 115 35.2 277 -15 125 25.7 278 -15 135 49.3 279 -15 145 43.8 280 -15 155 48.7 281 -15 165 42.9 282 -15 175 37.7 283 -15 185 43.8 284 -15 195 42.9 285 -15 205 52.5 286 -15 215 56.1 287 -15 225 60.9 288 -15 235 57.9 289 -15 245 47.7 290 -15 255 30.4 291 -15 265 26.5 292 -15 275 9.8 293 -15 285 8.1 297 -15 325 56.5 298 -15 335 46.4 299 -15 345 34.4 300 -15 355 9.4 301 -25 5 18.6 302 -25 15 21.2 304 -25 35 42.8 305 -25 45 45.6 306 -25 55 42.9 307 -25 65 34.5 308 -25 75 33.9 309 -25 85 29.1 310 -25 95 29.3 311 -25 105 39.3 312 -25 115 32.5 316 -25 155 43.8 317 -25 165 48.9 318 -25 175 37.4 319 -25 185 35.7 320 -25 195 35.9 321 -25 205 30.9 322 -25 215 37.1 323 -25 225 38.9 324 -25 235 40.6 325 -25 245 45.4 328 -25 275 22.5 329 -25 285 19.0 332 -25 315 25.1 333 -25 325 41.1 334 -25 335 35.7 335 -25 345 27.6 336 -25 355 21.6 337 -35 5 18.0 338 -35 15 27.5 339 -35 25 22.6 340 -35 35 34.2 341 -35 45 25.5 342 -35 55 26.4 343 -35 65 24.3 344 -35 75 18.9 345 -35 85 18.5 346 -35 95 19.1 347 -35 105 29.1 348 -35 115 32.6 349 -35 125 31.9 350 -35 135 27.6 351 -35 145 26.5 352 -35 155 34.4 353 -35 165 37.6 354 -35 175 32.3 355 -35 185 29.8 356 -35 195 40.1 357 -35 205 32.6 358 -35 215 26.6 359 -35 225 29.0 364 -35 275 32.9 365 -35 285 26.0 367 -35 305 13.1 368 -35 315 25.0 369 -35 325 24.6 370 -35 335 26.4 371 -35 345 32.8 372 -35 355 21.9 387 -45 145 26.6 388 -45 155 24.2 389 -45 165 29.5 390 -45 175 19.9 391 -45 185 19.5 392 -45 195 16.7 400 -45 275 19.4 401 -45 285 25.8 402 -45 295 16.5 403 -45 305 16.7 404 -45 315 20.4 417 -55 170 14.8 423 -55 290 17.6 424 -55 310 15.4 425 -55 330 11.5