Warning: Javascript must be enabled to use all the features on this page!


Page Loading - Please Wait...

Click to hideNews Bulletins

USGS Daily Statistics for Texas

Click to hide state-specific text

The statistics generated from this site are based on approved daily-mean data and may not match those published by the USGS in official publications. The user is responsible for assessment and use of statistics from this site. For more details on why the statistics may not match, click here.

USGS 08150700 Llano Rv nr Mason, TX


Mason County, Texas
Hydrologic Unit Code 12090204
Latitude  30°39'38", Longitude  99°06'32" NAD27
Drainage area 3,247  square miles
Contributing drainage area 3,242  square miles
Gage datum 1,225.60 feet above NAVD88
Output formats
HTML table of all data
Tab-separated data
Reselect output format

00060, Discharge, cubic feet per second,
Day of
month		 Mean of daily mean values for each day for water year of record in, ft3/s   (Calculation Period 1967-10-01 -> 2025-09-30)

Calculation period restricted by USGS staff due to special conditions at/near site
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
1 433 178 193 181 199 396 217 233 207 207 267 196
2 230 203 186 179 381 327 227 297 345 165 245 192
3 211 231 184 182 632 302 229 729 196 152 877 191
4 202 350 193 182 378 527 212 191 194 237 1,730 190
5 195 291 199 181 328 336 286 153 181 464 351 190
6 190 240 210 191 247 249 236 180 166 295 371 190
7 187 212 255 209 211 279 175 178 159 231 277 189
8 184 201 217 212 239 233 152 157 1,410 757 258 191
9 184 195 211 201 300 286 146 132 484 608 242 191
10 183 190 202 214 340 251 141 132 188 411 229 188
11 180 191 219 211 722 254 187 133 165 212 216 188
12 179 189 233 190 347 391 704 403 164 260 207 187
13 178 186 232 183 243 266 177 308 171 1,820 204 185
14 176 183 211 177 285 243 146 270 157 1,190 201 186
15 177 181 199 365 285 210 138 203 157 338 558 187
16 178 200 221 715 343 257 221 170 170 2,760 679 186
17 178 185 202 381 249 603 217 312 288 545 1,110 182
18 178 188 197 350 279 372 166 251 658 286 365 180
19 176 187 194 317 233 216 154 167 250 483 275 180
20 174 179 241 241 242 193 150 146 201 531 247 216
21 173 181 268 273 304 177 138 151 246 296 233 281
22 172 183 248 229 277 195 148 144 480 235 224 244
23 170 204 212 232 212 168 538 161 287 279 220 222
24 169 213 197 205 316 173 554 350 197 852 214 208
25 169 293 190 191 514 185 243 240 190 359 216 199
26 176 226 197 179 651 163 300 203 214 386 221 200
27 183 203 341 212 387 227 189 175 320 384 218 198
28 182 194 264 234 302 196 171 284 214 262 209 191
29 205 216 217 209 342 205 151 806 185 332 203 188
30 190   204 192 335 315 141 805 317 380 198 186
31 183   191   295   199 382   291   1,230