Nimbostratus Amount-When-Present (%) December, January, February (1954 - 1997) , Ship Observations Only Global Average: 98.7 Zonal Averages 17 zones Lat.N Average 85 97.5 75 98.4 65 99.1 55 99.1 45 99.0 35 98.9 25 98.5 15 97.7 5 98.3 -5 98.4 -15 98.3 -25 98.6 -35 99.0 -45 99.4 -55 99.4 -65 99.4 -75 99.0 Grid Box Averages 341 filled boxes Box # Lat.N Lon.E Average 1 85 60 97.9 2 85 180 96.8 4 75 20 98.9 5 75 60 98.9 7 75 140 96.6 8 75 180 98.3 9 75 220 98.1 12 75 340 99.5 13 65 10 99.2 14 65 30 98.8 15 65 50 98.8 21 65 170 99.7 22 65 190 99.4 23 65 210 99.8 27 65 290 98.4 29 65 330 99.2 30 65 350 99.0 31 55 10 99.3 32 55 30 99.5 38 55 150 99.2 39 55 170 99.0 40 55 190 98.9 41 55 210 99.2 42 55 230 99.4 46 55 310 99.3 47 55 330 99.2 48 55 350 99.2 49 45 5 99.1 50 45 15 98.8 51 45 25 99.2 52 45 35 99.3 62 45 135 99.0 63 45 145 98.8 64 45 155 98.3 65 45 165 98.2 66 45 175 98.8 67 45 185 99.2 68 45 195 99.3 69 45 205 99.3 70 45 215 99.3 71 45 225 99.2 72 45 235 99.3 77 45 285 99.6 78 45 295 99.3 79 45 305 99.3 80 45 315 99.2 81 45 325 98.9 82 45 335 99.0 83 45 345 98.9 84 45 355 99.0 85 35 5 98.4 86 35 15 98.4 87 35 25 97.8 88 35 35 97.7 97 35 125 98.9 98 35 135 99.0 99 35 145 98.9 100 35 155 98.6 101 35 165 98.9 102 35 175 98.9 103 35 185 99.0 104 35 195 99.0 105 35 205 99.1 106 35 215 99.1 107 35 225 99.0 108 35 235 98.9 109 35 245 98.0 112 35 275 99.5 113 35 285 99.4 114 35 295 99.0 115 35 305 98.9 116 35 315 98.8 117 35 325 98.7 118 35 335 98.4 119 35 345 97.8 120 35 355 98.3 126 25 55 98.2 132 25 115 99.6 133 25 125 99.3 134 25 135 99.2 135 25 145 98.7 136 25 155 98.5 137 25 165 98.4 138 25 175 98.7 139 25 185 98.3 140 25 195 98.3 141 25 205 98.5 142 25 215 98.5 143 25 225 98.3 144 25 235 99.1 145 25 245 99.2 146 25 255 99.1 147 25 265 99.2 148 25 275 98.6 149 25 285 98.3 150 25 295 97.9 151 25 305 97.5 152 25 315 97.2 153 25 325 97.2 154 25 335 96.6 155 25 345 97.8 161 15 45 98.1 162 15 55 96.0 163 15 65 97.3 165 15 85 98.3 167 15 105 99.3 168 15 115 98.5 169 15 125 98.4 170 15 135 98.3 171 15 145 97.7 172 15 155 97.5 173 15 165 96.4 174 15 175 97.5 175 15 185 97.4 176 15 195 98.1 177 15 205 97.0 178 15 215 98.0 179 15 225 98.7 180 15 235 98.3 181 15 245 98.3 182 15 255 98.7 183 15 265 98.5 184 15 275 97.0 185 15 285 96.0 186 15 295 96.1 187 15 305 96.7 188 15 315 92.3 189 15 325 95.7 190 15 335 98.3 191 15 345 97.7 193 5 5 97.8 198 5 55 95.8 199 5 65 97.1 200 5 75 98.2 201 5 85 98.2 202 5 95 98.2 203 5 105 98.9 204 5 115 98.1 205 5 125 98.6 206 5 135 98.8 207 5 145 98.6 208 5 155 98.2 209 5 165 99.3 210 5 175 96.0 211 5 185 97.9 212 5 195 98.0 213 5 205 98.6 214 5 215 98.0 215 5 225 98.2 216 5 235 98.6 217 5 245 98.6 218 5 255 98.9 219 5 265 98.7 220 5 275 98.5 221 5 285 98.5 223 5 305 97.6 224 5 315 98.0 225 5 325 98.4 226 5 335 99.0 227 5 345 98.0 228 5 355 97.9 229 -5 5 98.7 233 -5 45 98.0 234 -5 55 98.0 235 -5 65 98.0 236 -5 75 97.9 237 -5 85 98.0 238 -5 95 98.9 239 -5 105 99.2 240 -5 115 98.8 241 -5 125 98.4 242 -5 135 97.8 243 -5 145 98.3 244 -5 155 98.7 245 -5 165 98.6 246 -5 175 98.5 247 -5 185 99.3 248 -5 195 99.0 255 -5 265 98.6 256 -5 275 97.5 260 -5 315 98.1 261 -5 325 98.2 262 -5 335 95.9 264 -5 355 96.9 265 -15 5 97.3 266 -15 15 97.9 268 -15 35 97.4 269 -15 45 98.6 270 -15 55 97.8 271 -15 65 97.9 272 -15 75 98.0 273 -15 85 97.3 274 -15 95 98.6 275 -15 105 98.3 276 -15 115 99.0 277 -15 125 99.5 278 -15 135 98.7 279 -15 145 99.0 280 -15 155 98.4 281 -15 165 99.3 282 -15 175 98.6 283 -15 185 98.3 284 -15 195 98.8 285 -15 205 98.6 286 -15 215 97.9 287 -15 225 96.9 289 -15 245 92.2 297 -15 325 97.9 300 -15 355 97.1 301 -25 5 96.9 302 -25 15 98.5 304 -25 35 98.7 305 -25 45 98.3 306 -25 55 98.7 307 -25 65 99.1 308 -25 75 97.5 309 -25 85 98.0 310 -25 95 98.0 311 -25 105 98.4 312 -25 115 98.8 315 -25 145 99.4 316 -25 155 98.7 317 -25 165 98.9 318 -25 175 98.9 319 -25 185 98.8 320 -25 195 98.8 321 -25 205 99.6 322 -25 215 98.8 323 -25 225 98.6 324 -25 235 98.6 325 -25 245 96.9 332 -25 315 99.0 333 -25 325 98.4 334 -25 335 98.9 336 -25 355 95.8 337 -35 5 99.2 338 -35 15 97.9 339 -35 25 98.2 340 -35 35 99.3 341 -35 45 98.5 342 -35 55 99.2 343 -35 65 99.2 344 -35 75 98.7 345 -35 85 99.4 346 -35 95 98.8 347 -35 105 97.9 348 -35 115 97.8 349 -35 125 97.6 350 -35 135 98.1 351 -35 145 98.3 352 -35 155 98.8 353 -35 165 98.9 354 -35 175 99.1 355 -35 185 98.9 356 -35 195 98.9 357 -35 205 99.3 358 -35 215 99.6 359 -35 225 99.8 360 -35 235 98.8 363 -35 265 98.6 364 -35 275 98.5 365 -35 285 98.6 367 -35 305 98.5 368 -35 315 98.8 369 -35 325 99.6 370 -35 335 99.0 371 -35 345 99.3 372 -35 355 99.1 373 -45 5 99.7 374 -45 15 99.5 375 -45 25 99.3 376 -45 35 99.7 377 -45 45 99.8 378 -45 55 99.1 379 -45 65 99.2 380 -45 75 99.4 381 -45 85 99.5 382 -45 95 99.6 383 -45 105 99.5 384 -45 115 99.0 385 -45 125 99.3 386 -45 135 99.5 387 -45 145 98.7 388 -45 155 98.9 389 -45 165 99.3 390 -45 175 99.1 391 -45 185 99.3 392 -45 195 98.5 393 -45 205 99.3 394 -45 215 100.0 399 -45 265 99.3 400 -45 275 99.0 401 -45 285 99.4 402 -45 295 97.7 403 -45 305 98.7 404 -45 315 99.5 405 -45 325 99.3 406 -45 335 99.8 407 -45 345 99.8 408 -45 355 99.5 409 -55 10 99.6 410 -55 30 99.8 411 -55 50 99.7 412 -55 70 99.8 413 -55 90 99.7 414 -55 110 99.5 415 -55 130 99.4 416 -55 150 99.5 417 -55 170 99.3 418 -55 190 99.8 419 -55 210 99.3 420 -55 230 99.4 421 -55 250 99.2 422 -55 270 97.0 423 -55 290 98.4 424 -55 310 98.9 425 -55 330 99.5 426 -55 350 99.7 427 -65 10 98.8 428 -65 30 98.7 429 -65 50 99.0 430 -65 70 99.5 431 -65 90 99.3 432 -65 110 99.4 433 -65 130 99.6 434 -65 150 99.7 435 -65 170 99.6 436 -65 190 99.5 437 -65 210 99.8 438 -65 230 99.8 439 -65 250 99.5 440 -65 270 99.4 441 -65 290 99.2 442 -65 310 99.4 443 -65 330 99.4 444 -65 350 99.0 449 -75 180 99.0 450 -75 220 99.5 451 -75 260 98.6 452 -75 300 98.7 453 -75 340 99.0