Rivers in Texas

Llano River near Mason

Mason County, TexasNWS MLRT2USGS 08150700San Angelo office

Below flood stage
5.95ftStage

Observed Sun, Sep 20, 1:15 PM CDT

Flood stage
18.00 ft
Record crest
46.00 ft1935

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood28.00 ft
Moderate flood24.00 ft
Minor flood18.00 ft
Action11.00 ft
  1. 28.00 ftMajor lowland flooding will occur. Roads and low water crossings will be flooded and impassible.
  2. 24.00 ftModerate lowland flooding will occur. Secondary roads and low water crossings will be flooded and impassible.
  3. 18.00 ftMinor lowland flooding will occur. Secondary roads and low water crossings will become flooded.

Flood outlook

Chance of flooding, September to November

CategoryChance
Minor flooding9%
Moderate flooding6%
Major floodingUnder 5%

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued August 28, 2026.

Crest history

25 crests on NOAA’s list since 1935.

#DateStage
1June 14, 193546.00 ft
2September 8, 198037.00 ft
3October 16, 201834.21 ft
4November 4, 200032.00 ft
5June 13, 200831.33 ft
6July 4, 202529.91 ft
7July 18, 202626.97 ft
8October 13, 197326.30 ft
9December 31, 198425.22 ft
10October 13, 198125.06 ft
11July 24, 202424.08 ft
12October 8, 201822.68 ft
13November 17, 200421.59 ft
14August 3, 197821.35 ft
15July 14, 202520.29 ft
16October 5, 196918.53 ft
17July 12, 198818.40 ft
18November 15, 200117.74 ft
19May 3, 199017.49 ft
20April 16, 197716.64 ft
21August 24, 199816.38 ft
22September 18, 199014.78 ft
23October 9, 201814.53 ft
24September 17, 199110.13 ft
25June 13, 20080.61 ft

Most recent crests

  • July 18, 2026: 26.97 ft
  • July 14, 2025: 20.29 ft
  • July 4, 2025: 29.91 ft
  • July 24, 2024: 24.08 ft
  • October 16, 2018: 34.21 ft
  • October 9, 2018: 14.53 ft
  • October 8, 2018: 22.68 ft
  • June 13, 2008: 31.33 ft
  • June 13, 2008: 0.61 ft
  • November 17, 2004: 21.59 ft

Nearby

Upstream, downstream and the gauges around this one.

What this means

Forecasts by the West Gulf River Forecast Center. Forecasts are issued as needed during times of high water, but are not routinely available. River forecasts for this location take into account past precipitation and the precipitation amounts expected approximately 24 hours into the future from the forecast issuance time.

Sources

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.