Stratus Amount-When-Present (%) March, April, May (1954 - 1997) , Ship Observations Only Global Average: 83.1 Zonal Averages 17 zones Lat.N Average 85 86.5 75 88.1 65 85.9 55 90.1 45 89.5 35 85.2 25 80.6 15 74.8 5 79.4 -5 78.6 -15 79.3 -25 81.0 -35 84.7 -45 88.5 -55 90.4 -65 90.5 -75 84.9 Grid Box Averages 384 filled boxes Box # Lat.N Lon.E Average 1 85 60 86.9 2 85 180 88.8 3 85 300 83.7 4 75 20 88.8 5 75 60 91.6 7 75 140 84.3 8 75 180 91.3 9 75 220 92.4 11 75 300 75.2 12 75 340 83.2 13 65 10 84.3 14 65 30 88.2 15 65 50 85.3 20 65 150 89.6 21 65 170 95.9 22 65 190 92.8 23 65 210 89.9 29 65 330 82.5 30 65 350 83.7 31 55 10 84.7 32 55 30 83.9 37 55 130 89.6 38 55 150 91.2 39 55 170 93.5 40 55 190 91.8 41 55 210 91.1 42 55 230 91.3 46 55 310 88.3 47 55 330 88.6 48 55 350 86.3 49 45 5 75.8 50 45 15 74.9 51 45 25 84.8 52 45 35 86.6 53 45 45 71.5 54 45 55 74.5 62 45 135 86.7 63 45 145 87.9 64 45 155 90.7 65 45 165 91.7 66 45 175 91.7 67 45 185 91.3 68 45 195 90.8 69 45 205 91.4 70 45 215 90.9 71 45 225 90.2 72 45 235 88.3 77 45 285 82.8 78 45 295 87.4 79 45 305 89.0 80 45 315 88.7 81 45 325 88.1 82 45 335 87.6 83 45 345 86.7 84 45 355 84.5 85 35 5 76.1 86 35 15 73.3 87 35 25 72.6 88 35 35 73.3 89 35 45 66.9 90 35 55 81.0 96 35 115 81.1 97 35 125 83.4 98 35 135 84.2 99 35 145 87.2 100 35 155 88.9 101 35 165 87.7 102 35 175 88.0 103 35 185 87.7 104 35 195 87.6 105 35 205 87.7 106 35 215 87.3 107 35 225 86.6 108 35 235 85.8 109 35 245 83.4 112 35 275 73.3 113 35 285 79.9 114 35 295 84.1 115 35 305 83.5 116 35 315 81.1 117 35 325 82.1 118 35 335 82.6 119 35 345 81.2 120 35 355 74.2 124 25 35 63.6 125 25 45 76.6 126 25 55 66.9 127 25 65 58.4 129 25 85 58.3 131 25 105 89.5 132 25 115 85.9 133 25 125 85.3 134 25 135 82.0 135 25 145 81.7 136 25 155 82.8 137 25 165 82.1 138 25 175 81.6 139 25 185 81.5 140 25 195 81.1 141 25 205 81.2 142 25 215 82.8 143 25 225 83.7 144 25 235 84.0 145 25 245 77.8 146 25 255 59.0 147 25 265 75.9 148 25 275 72.1 149 25 285 73.3 150 25 295 77.0 151 25 305 78.1 152 25 315 77.6 153 25 325 77.3 154 25 335 74.7 155 25 345 72.0 160 15 35 66.9 161 15 45 60.3 162 15 55 64.2 163 15 65 62.3 164 15 75 64.5 165 15 85 58.0 166 15 95 60.9 167 15 105 79.2 168 15 115 72.1 169 15 125 76.0 170 15 135 78.4 171 15 145 76.8 172 15 155 76.2 173 15 165 78.4 174 15 175 78.1 175 15 185 74.7 176 15 195 76.6 177 15 205 78.7 178 15 215 80.3 179 15 225 84.7 180 15 235 84.7 181 15 245 77.4 182 15 255 62.2 183 15 265 63.1 184 15 275 68.5 185 15 285 70.3 186 15 295 69.8 187 15 305 71.8 188 15 315 72.4 189 15 325 74.2 190 15 335 69.4 191 15 345 68.7 193 5 5 76.1 197 5 45 71.7 198 5 55 71.6 199 5 65 70.1 200 5 75 70.3 201 5 85 72.7 202 5 95 74.2 203 5 105 69.3 204 5 115 72.2 205 5 125 78.2 206 5 135 78.8 207 5 145 82.3 208 5 155 83.8 209 5 165 81.3 210 5 175 82.5 211 5 185 81.5 212 5 195 82.1 213 5 205 81.1 214 5 215 85.3 215 5 225 84.0 216 5 235 83.1 217 5 245 78.6 218 5 255 82.2 219 5 265 76.4 220 5 275 76.5 221 5 285 76.3 223 5 305 77.7 224 5 315 78.5 225 5 325 80.7 226 5 335 77.2 227 5 345 75.4 228 5 355 74.3 229 -5 5 73.1 230 -5 15 71.7 233 -5 45 73.7 234 -5 55 73.3 235 -5 65 80.8 236 -5 75 79.6 237 -5 85 77.9 238 -5 95 79.0 239 -5 105 74.9 240 -5 115 75.6 241 -5 125 78.6 242 -5 135 77.8 243 -5 145 80.1 244 -5 155 82.1 245 -5 165 82.2 246 -5 175 82.8 247 -5 185 78.5 248 -5 195 78.0 249 -5 205 75.0 250 -5 215 83.5 251 -5 225 77.6 252 -5 235 81.5 253 -5 245 82.0 254 -5 255 82.9 255 -5 265 83.3 256 -5 275 73.7 257 -5 285 71.0 260 -5 315 76.6 261 -5 325 76.8 262 -5 335 77.5 263 -5 345 70.3 264 -5 355 75.0 265 -15 5 85.2 266 -15 15 82.7 268 -15 35 72.5 269 -15 45 73.0 270 -15 55 75.9 271 -15 65 77.5 272 -15 75 75.3 273 -15 85 78.1 274 -15 95 78.7 275 -15 105 76.8 276 -15 115 76.3 277 -15 125 80.0 278 -15 135 79.2 279 -15 145 81.6 280 -15 155 82.0 281 -15 165 81.2 282 -15 175 79.9 283 -15 185 80.5 284 -15 195 80.2 285 -15 205 81.4 286 -15 215 79.8 287 -15 225 78.7 288 -15 235 77.9 289 -15 245 77.1 290 -15 255 78.3 291 -15 265 83.3 292 -15 275 84.5 293 -15 285 77.8 297 -15 325 74.9 298 -15 335 70.0 299 -15 345 71.9 300 -15 355 81.9 301 -25 5 83.3 302 -25 15 82.7 304 -25 35 78.6 305 -25 45 76.3 306 -25 55 80.9 307 -25 65 81.5 308 -25 75 77.8 309 -25 85 79.0 310 -25 95 80.8 311 -25 105 79.5 312 -25 115 73.6 315 -25 145 85.6 316 -25 155 82.7 317 -25 165 81.7 318 -25 175 82.2 319 -25 185 81.8 320 -25 195 82.9 321 -25 205 84.0 322 -25 215 85.1 323 -25 225 82.6 324 -25 235 84.9 325 -25 245 80.8 326 -25 255 78.5 327 -25 265 73.0 328 -25 275 84.8 329 -25 285 88.1 332 -25 315 73.5 333 -25 325 75.0 334 -25 335 77.3 335 -25 345 79.8 336 -25 355 79.5 337 -35 5 83.9 338 -35 15 78.7 339 -35 25 81.3 340 -35 35 79.9 341 -35 45 84.4 342 -35 55 83.5 343 -35 65 85.0 344 -35 75 85.5 345 -35 85 85.7 346 -35 95 86.9 347 -35 105 83.6 348 -35 115 80.7 349 -35 125 82.9 350 -35 135 82.5 351 -35 145 83.3 352 -35 155 83.1 353 -35 165 84.4 354 -35 175 84.1 355 -35 185 84.3 356 -35 195 86.1 357 -35 205 87.2 358 -35 215 85.7 359 -35 225 87.4 360 -35 235 89.1 361 -35 245 81.0 362 -35 255 87.5 363 -35 265 84.9 364 -35 275 87.4 365 -35 285 87.2 367 -35 305 78.6 368 -35 315 80.2 369 -35 325 85.0 370 -35 335 85.2 371 -35 345 84.7 372 -35 355 84.6 373 -45 5 90.1 374 -45 15 82.6 375 -45 25 90.6 376 -45 35 89.2 377 -45 45 86.4 378 -45 55 90.0 379 -45 65 88.3 380 -45 75 87.5 381 -45 85 89.9 382 -45 95 91.0 383 -45 105 91.3 384 -45 115 91.0 385 -45 125 90.0 386 -45 135 88.0 387 -45 145 80.8 388 -45 155 86.3 389 -45 165 89.2 390 -45 175 83.9 391 -45 185 86.8 392 -45 195 86.3 393 -45 205 90.2 394 -45 215 88.0 395 -45 225 86.3 396 -45 235 88.4 397 -45 245 92.7 398 -45 255 92.6 399 -45 265 87.0 400 -45 275 91.3 401 -45 285 89.8 402 -45 295 82.2 403 -45 305 82.9 404 -45 315 88.2 405 -45 325 89.3 406 -45 335 91.1 407 -45 345 86.8 408 -45 355 87.7 409 -55 10 93.7 410 -55 30 93.4 411 -55 50 87.9 412 -55 70 89.7 413 -55 90 93.3 414 -55 110 86.4 415 -55 130 86.1 416 -55 150 90.8 417 -55 170 88.6 418 -55 190 90.4 419 -55 210 94.4 420 -55 230 91.3 421 -55 250 94.7 422 -55 270 88.5 423 -55 290 86.7 424 -55 310 88.3 425 -55 330 85.4 426 -55 350 94.5 427 -65 10 89.2 428 -65 30 89.9 429 -65 50 87.1 430 -65 70 91.5 431 -65 90 93.0 432 -65 110 87.1 433 -65 130 91.7 434 -65 150 90.5 435 -65 170 88.7 436 -65 190 87.9 437 -65 210 92.1 438 -65 230 92.9 439 -65 250 95.1 440 -65 270 95.7 441 -65 290 88.0 442 -65 310 88.2 443 -65 330 92.0 444 -65 350 85.3 449 -75 180 87.2 450 -75 220 91.0 451 -75 260 80.4 453 -75 340 79.2