Nimbostratus Amount-When-Present (%) March, April, May (1954 - 1997) Day, Ship Observations Only Global Average: 98.5 Zonal Averages 17 zones Lat.N Average 85 96.8 75 97.6 65 99.2 55 99.3 45 99.3 35 99.2 25 98.7 15 97.5 5 98.1 -5 98.0 -15 97.8 -25 98.3 -35 98.6 -45 98.9 -55 99.3 -65 99.4 -75 99.3 Grid Box Averages 317 filled boxes Box # Lat.N Lon.E Average 1 85 60 95.8 2 85 180 97.5 3 85 300 97.1 4 75 20 98.5 5 75 60 98.5 7 75 140 96.0 8 75 180 97.5 9 75 220 96.8 12 75 340 99.1 13 65 10 99.1 14 65 30 98.5 15 65 50 98.4 21 65 170 99.8 22 65 190 99.2 23 65 210 99.5 29 65 330 99.3 30 65 350 99.4 31 55 10 99.3 32 55 30 99.5 38 55 150 99.2 39 55 170 99.1 40 55 190 99.2 41 55 210 99.3 42 55 230 99.2 46 55 310 99.6 47 55 330 99.3 48 55 350 99.0 49 45 5 98.9 50 45 15 98.5 51 45 25 99.7 52 45 35 99.0 62 45 135 99.3 63 45 145 99.3 64 45 155 99.1 65 45 165 99.2 66 45 175 99.2 67 45 185 99.4 68 45 195 99.5 69 45 205 99.3 70 45 215 99.3 71 45 225 99.3 72 45 235 99.2 77 45 285 99.4 78 45 295 99.7 79 45 305 99.6 80 45 315 99.4 81 45 325 99.1 82 45 335 99.1 83 45 345 99.0 84 45 355 99.0 85 35 5 98.7 86 35 15 98.5 87 35 25 98.1 88 35 35 98.1 97 35 125 99.5 98 35 135 99.5 99 35 145 99.6 100 35 155 99.5 101 35 165 99.4 102 35 175 99.3 103 35 185 99.2 104 35 195 99.3 105 35 205 99.2 106 35 215 98.6 107 35 225 98.6 108 35 235 98.4 109 35 245 98.7 112 35 275 98.0 113 35 285 99.1 114 35 295 99.2 115 35 305 99.0 116 35 315 99.0 117 35 325 98.7 118 35 335 98.5 119 35 345 97.7 120 35 355 98.3 126 25 55 98.5 132 25 115 99.3 133 25 125 99.3 134 25 135 99.4 135 25 145 98.9 136 25 155 99.2 137 25 165 99.1 138 25 175 98.5 139 25 185 98.8 140 25 195 98.3 141 25 205 96.9 142 25 215 98.0 143 25 225 97.5 144 25 235 97.0 147 25 265 98.8 148 25 275 98.8 149 25 285 98.6 150 25 295 98.5 151 25 305 98.2 152 25 315 97.7 153 25 325 97.1 154 25 335 97.0 155 25 345 96.5 161 15 45 96.4 162 15 55 97.6 163 15 65 97.3 164 15 75 96.6 165 15 85 99.1 167 15 105 98.8 168 15 115 98.5 169 15 125 98.2 170 15 135 97.9 171 15 145 96.7 172 15 155 98.1 176 15 195 95.6 177 15 205 98.0 178 15 215 97.1 179 15 225 97.0 180 15 235 98.6 182 15 255 98.1 183 15 265 98.5 184 15 275 98.1 185 15 285 97.3 186 15 295 96.1 187 15 305 96.0 188 15 315 97.0 191 15 345 94.0 193 5 5 99.0 198 5 55 95.8 199 5 65 97.7 200 5 75 98.0 201 5 85 98.0 202 5 95 98.3 203 5 105 97.4 204 5 115 97.8 205 5 125 98.1 206 5 135 97.2 207 5 145 97.7 208 5 155 98.3 209 5 165 98.2 211 5 185 97.8 212 5 195 98.0 213 5 205 97.1 214 5 215 97.6 215 5 225 98.6 216 5 235 98.5 217 5 245 98.6 218 5 255 99.4 219 5 265 98.8 220 5 275 98.6 221 5 285 99.2 223 5 305 97.6 224 5 315 98.2 225 5 325 98.7 226 5 335 98.5 227 5 345 98.4 228 5 355 97.8 229 -5 5 96.9 230 -5 15 99.6 233 -5 45 97.5 235 -5 65 98.8 236 -5 75 97.9 237 -5 85 97.7 238 -5 95 98.3 239 -5 105 97.7 240 -5 115 98.4 241 -5 125 98.4 242 -5 135 98.4 243 -5 145 98.2 244 -5 155 98.3 245 -5 165 97.8 253 -5 245 96.6 254 -5 255 97.8 255 -5 265 97.9 256 -5 275 97.8 260 -5 315 98.8 261 -5 325 97.5 262 -5 335 97.4 264 -5 355 97.3 265 -15 5 96.0 266 -15 15 98.1 269 -15 45 97.4 270 -15 55 97.3 271 -15 65 96.7 272 -15 75 97.7 273 -15 85 97.7 274 -15 95 97.8 275 -15 105 97.1 276 -15 115 98.5 277 -15 125 98.9 278 -15 135 98.9 279 -15 145 98.5 280 -15 155 98.6 281 -15 165 97.7 282 -15 175 98.2 283 -15 185 97.7 284 -15 195 97.8 285 -15 205 96.9 286 -15 215 95.8 297 -15 325 97.4 301 -25 5 96.0 302 -25 15 97.0 304 -25 35 97.3 305 -25 45 97.9 306 -25 55 97.1 307 -25 65 95.9 308 -25 75 97.9 309 -25 85 98.2 310 -25 95 99.2 311 -25 105 97.1 312 -25 115 98.2 316 -25 155 97.9 317 -25 165 98.5 318 -25 175 99.1 319 -25 185 99.2 320 -25 195 99.7 321 -25 205 99.0 322 -25 215 98.5 323 -25 225 98.4 324 -25 235 98.6 325 -25 245 96.6 332 -25 315 98.2 333 -25 325 97.1 334 -25 335 98.2 335 -25 345 99.5 336 -25 355 95.2 337 -35 5 98.7 338 -35 15 97.3 339 -35 25 98.0 340 -35 35 97.8 341 -35 45 98.5 342 -35 55 98.7 343 -35 65 98.8 344 -35 75 97.8 345 -35 85 98.8 346 -35 95 98.3 347 -35 105 97.2 348 -35 115 97.3 349 -35 125 97.2 350 -35 135 97.5 351 -35 145 98.2 352 -35 155 98.0 353 -35 165 98.0 354 -35 175 98.8 355 -35 185 98.8 356 -35 195 98.5 357 -35 205 98.9 358 -35 215 99.2 359 -35 225 99.0 360 -35 235 99.1 363 -35 265 99.0 364 -35 275 97.8 365 -35 285 99.4 367 -35 305 98.4 368 -35 315 98.5 369 -35 325 98.7 370 -35 335 99.2 371 -35 345 99.3 372 -35 355 98.7 375 -45 25 98.9 376 -45 35 99.3 377 -45 45 98.5 378 -45 55 99.9 379 -45 65 99.2 380 -45 75 98.8 383 -45 105 99.5 384 -45 115 99.4 385 -45 125 98.0 386 -45 135 97.9 387 -45 145 98.8 388 -45 155 96.7 389 -45 165 98.6 390 -45 175 98.6 391 -45 185 98.7 392 -45 195 98.0 393 -45 205 98.3 394 -45 215 99.4 395 -45 225 100.0 397 -45 245 99.1 398 -45 255 99.6 399 -45 265 98.9 400 -45 275 98.7 401 -45 285 99.0 402 -45 295 97.9 403 -45 305 98.1 404 -45 315 99.0 405 -45 325 97.5 409 -55 10 99.8 410 -55 30 99.3 411 -55 50 99.6 412 -55 70 99.5 413 -55 90 99.5 416 -55 150 99.6 417 -55 170 99.6 419 -55 210 99.7 420 -55 230 99.6 421 -55 250 97.8 422 -55 270 98.4 423 -55 290 98.6 424 -55 310 98.9 425 -55 330 98.9 426 -55 350 99.6 427 -65 10 99.8 428 -65 30 99.5 429 -65 50 99.6 430 -65 70 99.5 431 -65 90 99.6 432 -65 110 99.4 433 -65 130 99.6 434 -65 150 99.6 435 -65 170 99.9 436 -65 190 99.7 437 -65 210 99.7 440 -65 270 99.5 441 -65 290 98.6 442 -65 310 99.4 443 -65 330 99.3 444 -65 350 97.8 449 -75 180 99.6 450 -75 220 99.1 453 -75 340 99.1