WEST BRANCH HERRING RUN AT IDLEWYLDE, MD

Rising over 24 hours: discharge up 4,016.7%, from 0.6 to 24.7 ft³/s. Rising or falling means a change of more than 10% in discharge (or 0.2 ft of gauge height) over 24 hours; our rule of thumb, not a USGS class.

• Below NWS action stage. The National Weather Service reports this gauge below its action stage. That is not a statement that wading is safe.

  Flood categories: action stage, minor, moderate and major flooding (National Weather Service)

• Rising water. Rising over the last 24 hours (discharge up 4,017%). Keep your way back to the bank in sight and watch the level while you fish. “Rising” is our rule of thumb: more than 10% in discharge or 0.2 ft of gauge height in 24 hours, not a USGS or NWS class.

• Flow above the record for this date. Higher than any daily mean USGS has recorded on this date at this gauge. Expect much higher, faster water than usual for the season.

  hyswap: flow categories (WDFN_stats schema) (U.S. Geological Survey) Statistics documentation (percentiles of daily mean discharge) (U.S. Geological Survey)

• Turn Around Don't Drown. “A mere 6 inches of fast-moving flood water can knock over an adult.” No flow number makes a crossing safe; if in doubt, stay out.

  Turn Around Don't Drown (National Weather Service)

Guidance from the readings above and the published thresholds named with each line; not a fishing forecast, a safety guarantee or a statement about access. Local rules and closures come first.

USGS gauge page USGS statistics NWS gauge IDLM2

Checked Nov 5, 10:21 PM EST; readings refresh at most every 15 minutes and statistics daily. Provisional USGS data can be revised. Conditions change: re-check before you go. This is general guidance, not a fishing forecast, a safety guarantee or a statement about access.