High Level (Cirriform) Frequency of Occurrence (%) January (1954 - 1997) , Ship Observations Only Global Average: 34.2 Zonal Averages 17 zones Lat.N Average 85 54.0 75 41.3 65 25.4 55 28.8 45 29.5 35 30.1 25 24.7 15 24.9 5 38.1 -5 39.8 -15 37.9 -25 32.1 -35 31.8 -45 35.2 -55 38.5 -65 42.8 -75 53.6 Grid Box Averages 378 filled boxes Box # Lat.N Lon.E Average 1 85 60 75.0 2 85 180 46.9 3 85 300 35.3 4 75 20 21.8 5 75 60 14.6 7 75 140 39.5 8 75 180 52.3 9 75 220 79.5 12 75 340 31.1 13 65 10 23.4 14 65 30 27.9 15 65 50 22.1 21 65 170 18.8 22 65 190 15.2 23 65 210 34.3 29 65 330 36.1 30 65 350 26.0 31 55 10 27.0 32 55 30 25.1 38 55 150 26.2 39 55 170 26.4 40 55 190 25.7 41 55 210 29.7 42 55 230 32.8 46 55 310 27.5 47 55 330 30.2 48 55 350 36.4 49 45 5 35.0 50 45 15 29.5 51 45 25 21.9 52 45 35 21.3 53 45 45 25.4 54 45 55 28.3 62 45 135 18.9 63 45 145 21.2 64 45 155 23.6 65 45 165 24.4 66 45 175 29.2 67 45 185 29.9 68 45 195 29.3 69 45 205 34.0 70 45 215 35.1 71 45 225 34.7 72 45 235 37.2 77 45 285 32.8 78 45 295 28.9 79 45 305 29.2 80 45 315 30.1 81 45 325 30.0 82 45 335 32.3 83 45 345 30.9 84 45 355 30.7 85 35 5 31.1 86 35 15 27.2 87 35 25 25.6 88 35 35 25.5 90 35 55 35.1 96 35 115 29.9 97 35 125 18.9 98 35 135 21.6 99 35 145 20.6 100 35 155 21.1 101 35 165 22.9 102 35 175 25.4 103 35 185 28.2 104 35 195 29.8 105 35 205 35.4 106 35 215 39.1 107 35 225 35.5 108 35 235 33.4 109 35 245 35.8 112 35 275 37.8 113 35 285 33.7 114 35 295 33.0 115 35 305 34.3 116 35 315 35.6 117 35 325 35.7 118 35 335 34.8 119 35 345 31.5 120 35 355 31.1 124 25 35 20.5 125 25 45 25.3 126 25 55 21.8 127 25 65 19.5 128 25 75 14.1 129 25 85 25.2 130 25 95 21.6 132 25 115 18.4 133 25 125 19.6 134 25 135 17.6 135 25 145 18.2 136 25 155 18.7 137 25 165 18.6 138 25 175 17.1 139 25 185 20.8 140 25 195 22.2 141 25 205 24.8 142 25 215 31.3 143 25 225 35.1 144 25 235 35.1 145 25 245 36.2 146 25 255 39.6 147 25 265 36.8 148 25 275 33.1 149 25 285 28.4 150 25 295 22.8 151 25 305 22.2 152 25 315 24.6 153 25 325 23.7 154 25 335 23.4 155 25 345 25.0 160 15 35 18.4 161 15 45 15.6 162 15 55 14.3 163 15 65 16.8 164 15 75 23.4 165 15 85 26.2 166 15 95 34.2 167 15 105 31.6 168 15 115 28.0 169 15 125 30.5 170 15 135 32.9 171 15 145 31.6 172 15 155 25.6 173 15 165 17.9 174 15 175 15.4 175 15 185 17.0 176 15 195 19.0 177 15 205 21.5 178 15 215 28.0 179 15 225 29.6 180 15 235 35.0 181 15 245 35.8 182 15 255 33.6 183 15 265 23.0 184 15 275 28.6 185 15 285 22.4 186 15 295 17.9 187 15 305 16.7 188 15 315 19.8 189 15 325 23.1 190 15 335 29.3 191 15 345 34.1 193 5 5 35.5 197 5 45 22.6 198 5 55 20.8 199 5 65 27.5 200 5 75 35.9 201 5 85 47.6 202 5 95 55.7 203 5 105 50.4 204 5 115 50.7 205 5 125 52.7 206 5 135 65.6 207 5 145 50.7 208 5 155 51.9 209 5 165 48.7 210 5 175 51.0 211 5 185 47.3 212 5 195 37.8 213 5 205 32.8 214 5 215 26.4 215 5 225 27.1 216 5 235 20.9 217 5 245 29.3 218 5 255 25.6 219 5 265 25.1 220 5 275 33.0 221 5 285 34.1 223 5 305 31.0 224 5 315 39.7 225 5 325 36.7 226 5 335 35.0 227 5 345 28.6 228 5 355 29.4 229 -5 5 33.5 230 -5 15 43.5 232 -5 35 44.2 233 -5 45 34.7 234 -5 55 41.6 235 -5 65 50.2 236 -5 75 55.6 237 -5 85 57.9 238 -5 95 64.1 239 -5 105 67.3 240 -5 115 66.3 241 -5 125 63.0 242 -5 135 63.6 243 -5 145 62.9 244 -5 155 60.4 245 -5 165 62.7 246 -5 175 62.7 247 -5 185 55.8 248 -5 195 42.2 249 -5 205 26.4 250 -5 215 24.0 251 -5 225 18.6 252 -5 235 16.4 253 -5 245 12.6 254 -5 255 10.6 255 -5 265 13.1 256 -5 275 35.0 257 -5 285 35.5 260 -5 315 48.2 261 -5 325 34.6 262 -5 335 23.5 263 -5 345 17.2 264 -5 355 20.2 265 -15 5 23.5 266 -15 15 35.1 268 -15 35 47.2 269 -15 45 54.7 270 -15 55 47.0 271 -15 65 41.7 272 -15 75 41.2 273 -15 85 41.8 274 -15 95 41.3 275 -15 105 42.9 276 -15 115 38.0 277 -15 125 51.2 278 -15 135 59.0 279 -15 145 52.1 280 -15 155 44.8 281 -15 165 48.5 282 -15 175 56.2 283 -15 185 58.1 284 -15 195 56.4 285 -15 205 51.3 286 -15 215 39.7 287 -15 225 29.7 288 -15 235 27.7 289 -15 245 24.9 290 -15 255 19.1 291 -15 265 19.5 292 -15 275 21.6 293 -15 285 42.2 297 -15 325 37.8 298 -15 335 20.7 299 -15 345 18.1 300 -15 355 20.6 301 -25 5 14.1 302 -25 15 15.9 304 -25 35 33.1 305 -25 45 33.4 306 -25 55 37.6 307 -25 65 33.5 308 -25 75 31.4 309 -25 85 23.3 310 -25 95 21.4 311 -25 105 25.4 312 -25 115 25.8 315 -25 145 42.6 316 -25 155 33.6 317 -25 165 33.5 318 -25 175 40.1 319 -25 185 41.1 320 -25 195 47.7 321 -25 205 50.5 322 -25 215 49.0 323 -25 225 42.3 324 -25 235 34.1 325 -25 245 30.4 326 -25 255 30.6 327 -25 265 24.7 328 -25 275 20.7 329 -25 285 22.4 332 -25 315 43.5 333 -25 325 40.9 334 -25 335 33.4 335 -25 345 25.5 336 -25 355 18.1 337 -35 5 26.9 338 -35 15 20.2 339 -35 25 28.6 340 -35 35 29.7 341 -35 45 28.2 342 -35 55 29.5 343 -35 65 29.5 344 -35 75 30.9 345 -35 85 31.9 346 -35 95 30.9 347 -35 105 29.1 348 -35 115 26.5 349 -35 125 28.7 350 -35 135 29.9 351 -35 145 30.1 352 -35 155 29.7 353 -35 165 33.4 354 -35 175 36.7 355 -35 185 39.0 356 -35 195 39.4 357 -35 205 43.4 358 -35 215 37.6 359 -35 225 43.8 360 -35 235 37.5 361 -35 245 28.7 362 -35 255 31.0 363 -35 265 26.2 364 -35 275 21.1 365 -35 285 17.9 367 -35 305 37.1 368 -35 315 30.8 369 -35 325 30.8 370 -35 335 39.9 371 -35 345 38.4 372 -35 355 32.8 373 -45 5 25.6 374 -45 15 35.0 375 -45 25 34.0 376 -45 35 34.2 377 -45 45 30.7 378 -45 55 31.8 379 -45 65 31.3 380 -45 75 37.5 381 -45 85 26.9 382 -45 95 41.2 383 -45 105 33.9 384 -45 115 27.5 385 -45 125 33.7 386 -45 135 38.0 387 -45 145 35.9 388 -45 155 35.4 389 -45 165 41.9 390 -45 175 43.7 391 -45 185 39.0 392 -45 195 45.5 393 -45 205 41.9 394 -45 215 44.4 395 -45 225 39.0 396 -45 235 43.7 397 -45 245 29.6 399 -45 265 25.8 400 -45 275 24.4 401 -45 285 26.6 402 -45 295 45.9 403 -45 305 43.9 404 -45 315 38.6 405 -45 325 34.6 406 -45 335 32.7 407 -45 345 29.5 408 -45 355 32.0 409 -55 10 38.1 410 -55 30 35.3 411 -55 50 36.5 412 -55 70 37.2 413 -55 90 48.8 414 -55 110 38.8 415 -55 130 40.8 416 -55 150 31.8 417 -55 170 30.1 418 -55 190 43.2 421 -55 250 39.7 422 -55 270 31.6 423 -55 290 56.3 424 -55 310 41.0 425 -55 330 29.8 426 -55 350 39.6 427 -65 10 35.2 428 -65 30 46.8 429 -65 50 44.8 430 -65 70 36.0 431 -65 90 35.2 432 -65 110 41.5 433 -65 130 49.6 434 -65 150 45.7 435 -65 170 31.6 436 -65 190 44.4 437 -65 210 48.3 438 -65 230 44.5 439 -65 250 40.4 440 -65 270 46.4 441 -65 290 55.4 442 -65 310 45.8 443 -65 330 44.6 444 -65 350 35.9 449 -75 180 48.8 452 -75 300 62.4 453 -75 340 53.2