DIFFICULT RUN NEAR GREAT FALLS, VA
USGS 01646000 · Virginia · reports discharge (live), gauge height, water temperature, dissolved oxygen, pH, turbidity, specific conductance
Reading DIFFICULT RUN NEAR GREAT FALLS, VA…
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USGS 01646000 · Virginia · reports discharge (live), gauge height, water temperature, dissolved oxygen, pH, turbidity, specific conductance
What the agencies suggest
Carry a pocket thermometer to monitor water temperatureNational Park Service
General guidance from the readings and the published lines named above, not a fishing forecast. Local rules and closures come first.
Reading Nov 5, 9:15 PM EST · provisional USGS data
Below normal for Nov 5 Steady · 24 h Below NWS action stage
Discharge, last 7 days: 169 readings from Oct 29, 10:15 PM EDT to Nov 5, 9:15 PM EST; ranging 10.5 to 12.7 ft³/s; latest 12.7 ft³/s; shaded band: typical range (25th–75th percentile) for each date.
USGS provisional data may be revised. Source: USGS instantaneous values.
| Time | Discharge (ft³/s) | Gauge height (ft) | Water temp (°F) | Normal, 25th–75th (ft³/s) |
|---|---|---|---|---|
| Nov 5, 9:15 PM EST | 12.7 | 2.7 | 60.4 | 18–44 |
| Nov 5, 8:15 PM EST | 12.3 | 2.69 | 60.4 | 18–44 |
| Nov 5, 7:15 PM EST | 12 | 2.68 | 60.4 | 18–44 |
| Nov 5, 6:15 PM EST | 12 | 2.68 | 60.6 | 18–44 |
| Nov 5, 5:15 PM EST | 12 | 2.68 | 60.6 | 18–44 |
| Nov 5, 4:15 PM EST | 11.6 | 2.67 | 60.8 | 18–44 |
| Nov 5, 3:15 PM EST | 11.6 | 2.67 | 60.8 | 18–44 |
| Nov 5, 2:15 PM EST | 11.6 | 2.67 | 60.6 | 18–44 |
| Nov 5, 1:15 PM EST | 11.6 | 2.67 | 60.1 | 18–44 |
| Nov 5, 12:15 PM EST | 11.6 | 2.67 | 59.5 | 18–44 |
| Nov 5, 11:15 AM EST | 12 | 2.68 | 59 | 18–44 |
| Nov 5, 10:15 AM EST | 12 | 2.68 | 58.5 | 18–44 |
| Nov 5, 9:15 AM EST | 11.6 | 2.67 | 58.1 | 18–44 |
| Nov 5, 8:15 AM EST | 11.6 | 2.67 | 57.6 | 18–44 |
| Nov 5, 7:15 AM EST | 11.2 | 2.66 | 57.2 | 18–44 |
| Nov 5, 6:15 AM EST | 11.2 | 2.66 | 57.2 | 18–44 |
| Nov 5, 5:15 AM EST | 10.9 | 2.65 | 56.8 | 18–44 |
| Nov 5, 4:15 AM EST | 11.2 | 2.66 | 56.7 | 18–44 |
| Nov 5, 3:15 AM EST | 11.6 | 2.67 | 56.5 | 18–44 |
| Nov 5, 2:15 AM EST | 11.6 | 2.67 | 56.3 | 18–44 |
| Nov 5, 1:15 AM EST | 11.6 | 2.67 | 56.1 | 18–44 |
| Nov 5, 12:15 AM EST | 11.6 | 2.67 | 56.1 | 18–44 |
| Nov 4, 11:15 PM EST | 11.6 | 2.67 | 55.9 | 16–40 |
| Nov 4, 10:15 PM EST | 11.6 | 2.67 | 55.9 | 16–40 |
| Nov 4, 9:15 PM EST | 11.6 | 2.67 | 55.9 | 16–40 |
| Nov 4, 8:15 PM EST | 11.6 | 2.67 | 55.9 | 16–40 |
| Nov 4, 7:15 PM EST | 11.6 | 2.67 | 56.1 | 16–40 |
| Nov 4, 6:15 PM EST | 11.6 | 2.67 | 56.1 | 16–40 |
| Nov 4, 5:15 PM EST | 11.6 | 2.67 | 56.3 | 16–40 |
| Nov 4, 4:15 PM EST | 11.2 | 2.66 | 56.7 | 16–40 |
| Nov 4, 3:15 PM EST | 11.2 | 2.66 | 56.8 | 16–40 |
| Nov 4, 2:15 PM EST | 11.2 | 2.66 | 56.7 | 16–40 |
| Nov 4, 1:15 PM EST | 10.9 | 2.65 | 56.1 | 16–40 |
| Nov 4, 12:15 PM EST | 11.2 | 2.66 | 55.2 | 16–40 |
| Nov 4, 11:15 AM EST | 10.9 | 2.65 | 54.5 | 16–40 |
| Nov 4, 10:15 AM EST | 10.9 | 2.65 | 54 | 16–40 |
| Nov 4, 9:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 4, 8:15 AM EST | 10.9 | 2.65 | 53.1 | 16–40 |
| Nov 4, 7:15 AM EST | 10.9 | 2.65 | 53.1 | 16–40 |
| Nov 4, 6:15 AM EST | 10.9 | 2.65 | 53.2 | 16–40 |
| Nov 4, 5:15 AM EST | 10.9 | 2.65 | 53.2 | 16–40 |
| Nov 4, 4:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 4, 3:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 4, 2:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 4, 1:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 4, 12:15 AM EST | 10.9 | 2.65 | 53.4 | 16–40 |
| Nov 3, 11:15 PM EST | 10.9 | 2.65 | 53.6 | 17–42 |
| Nov 3, 10:15 PM EST | 10.9 | 2.65 | 53.6 | 17–42 |
| Nov 3, 9:15 PM EST | 10.9 | 2.65 | 54 | 17–42 |
| Nov 3, 8:15 PM EST | 10.9 | 2.65 | 54 | 17–42 |
| Nov 3, 7:15 PM EST | 11.2 | 2.66 | 54.1 | 17–42 |
| Nov 3, 6:15 PM EST | 11.2 | 2.66 | 54.3 | 17–42 |
| Nov 3, 5:15 PM EST | 11.2 | 2.66 | 54.3 | 17–42 |
| Nov 3, 4:15 PM EST | 11.2 | 2.66 | 54.7 | 17–42 |
| Nov 3, 3:15 PM EST | 11.2 | 2.66 | 54.9 | 17–42 |
| Nov 3, 2:15 PM EST | 11.2 | 2.66 | 54.9 | 17–42 |
| Nov 3, 1:15 PM EST | 11.2 | 2.66 | 54.3 | 17–42 |
| Nov 3, 12:15 PM EST | 11.2 | 2.66 | 53.4 | 17–42 |
| Nov 3, 11:15 AM EST | 10.9 | 2.65 | 52.7 | 17–42 |
| Nov 3, 10:15 AM EST | 10.9 | 2.65 | 52.2 | 17–42 |
| Nov 3, 9:15 AM EST | 10.9 | 2.65 | 51.6 | 17–42 |
| Nov 3, 8:15 AM EST | 10.5 | 2.64 | 51.4 | 17–42 |
| Nov 3, 7:15 AM EST | 10.5 | 2.64 | 51.4 | 17–42 |
| Nov 3, 6:15 AM EST | 10.9 | 2.65 | 51.4 | 17–42 |
| Nov 3, 5:15 AM EST | 10.5 | 2.64 | 51.6 | 17–42 |
| Nov 3, 4:15 AM EST | 10.5 | 2.64 | 51.8 | 17–42 |
| Nov 3, 3:15 AM EST | 10.9 | 2.65 | 52 | 17–42 |
| Nov 3, 2:15 AM EST | 10.5 | 2.64 | 52.2 | 17–42 |
| Nov 3, 1:15 AM EST | 10.9 | 2.65 | 52.3 | 17–42 |
| Nov 3, 12:15 AM EST | 10.9 | 2.65 | 52.5 | 17–42 |
| Nov 2, 11:15 PM EST | 10.9 | 2.65 | 52.7 | 17–46 |
| Nov 2, 10:15 PM EST | 10.9 | 2.65 | 52.9 | 17–46 |
| Nov 2, 9:15 PM EST | 10.9 | 2.65 | 53.1 | 17–46 |
| Nov 2, 8:15 PM EST | 10.9 | 2.65 | 53.4 | 17–46 |
| Nov 2, 7:15 PM EST | 10.9 | 2.65 | 53.6 | 17–46 |
| Nov 2, 6:15 PM EST | 10.5 | 2.64 | 54 | 17–46 |
| Nov 2, 5:15 PM EST | 10.5 | 2.64 | 54.3 | 17–46 |
| Nov 2, 4:15 PM EST | 10.9 | 2.65 | 54.3 | 17–46 |
| Nov 2, 3:15 PM EST | 10.5 | 2.64 | 54.3 | 17–46 |
| Nov 2, 2:15 PM EST | 10.5 | 2.64 | 54.3 | 17–46 |
| Nov 2, 1:15 PM EST | 10.5 | 2.64 | 54 | 17–46 |
| Nov 2, 12:15 PM EST | 10.5 | 2.64 | 53.4 | 17–46 |
| Nov 2, 11:15 AM EST | 10.5 | 2.64 | 53.1 | 17–46 |
| Nov 2, 10:15 AM EST | 10.5 | 2.64 | 52.7 | 17–46 |
| Nov 2, 9:15 AM EST | 10.5 | 2.64 | 52.2 | 17–46 |
| Nov 2, 8:15 AM EST | 10.5 | 2.64 | 51.8 | 17–46 |
| Nov 2, 7:15 AM EST | 10.5 | 2.64 | 51.8 | 17–46 |
| Nov 2, 6:15 AM EST | 10.5 | 2.64 | 51.8 | 17–46 |
| Nov 2, 5:15 AM EST | 10.5 | 2.64 | 52 | 17–46 |
| Nov 2, 4:15 AM EST | 10.5 | 2.64 | 52.2 | 17–46 |
| Nov 2, 3:15 AM EST | 10.5 | 2.64 | 52.3 | 17–46 |
| Nov 2, 2:15 AM EST | 10.5 | 2.64 | 52.5 | 17–46 |
| Nov 2, 1:15 AM EST | 10.5 | 2.64 | 52.7 | 17–46 |
| Nov 2, 12:15 AM EST | 10.5 | 2.64 | 52.9 | 17–46 |
| Nov 1, 11:15 PM EST | 10.5 | 2.64 | 53.2 | 16–44 |
| Nov 1, 10:15 PM EST | 10.5 | 2.64 | 53.4 | 16–44 |
| Nov 1, 9:15 PM EST | 10.5 | 2.64 | 53.6 | 16–44 |
| Nov 1, 8:15 PM EST | 10.5 | 2.64 | 54 | 16–44 |
| Nov 1, 7:15 PM EST | 10.5 | 2.64 | 54.1 | 16–44 |
| Nov 1, 6:15 PM EST | 10.5 | 2.64 | 54.5 | 16–44 |
| Nov 1, 5:15 PM EST | 10.5 | 2.64 | 54.7 | 16–44 |
| Nov 1, 4:15 PM EST | 10.5 | 2.64 | 54.9 | 16–44 |
| Nov 1, 3:15 PM EST | 10.5 | 2.64 | 55 | 16–44 |
| Nov 1, 2:15 PM EST | 10.5 | 2.64 | 55 | 16–44 |
| Nov 1, 1:15 PM EST | 10.5 | 2.64 | 54.9 | 16–44 |
| Nov 1, 12:15 PM EST | 10.5 | 2.64 | 54.3 | 16–44 |
| Nov 1, 11:15 AM EST | 10.5 | 2.64 | 54 | 16–44 |
| Nov 1, 10:15 AM EST | 10.5 | 2.64 | 53.4 | 16–44 |
| Nov 1, 9:15 AM EST | 10.5 | 2.64 | 53.1 | 16–44 |
| Nov 1, 8:15 AM EST | 10.5 | 2.64 | 52.9 | 16–44 |
| Nov 1, 7:15 AM EST | 10.5 | 2.64 | 52.9 | 16–44 |
| Nov 1, 6:15 AM EST | 10.5 | 2.64 | 53.1 | 16–44 |
| Nov 1, 5:15 AM EST | 10.5 | 2.64 | 53.2 | 16–44 |
| Nov 1, 4:15 AM EST | 10.5 | 2.64 | 53.4 | 16–44 |
| Nov 1, 3:15 AM EST | 10.5 | 2.64 | 53.6 | 16–44 |
| Nov 1, 2:15 AM EST | 10.5 | 2.64 | 53.6 | 16–44 |
| Nov 1, 1:15 AM EST | 10.5 | 2.64 | 53.6 | 16–44 |
| Nov 1, 1:15 AM EDT | 10.9 | 2.65 | 53.8 | 16–44 |
| Nov 1, 12:15 AM EDT | 10.9 | 2.65 | 53.8 | 16–44 |
| Oct 31, 11:15 PM EDT | 10.9 | 2.65 | 54 | 16–44 |
| Oct 31, 10:15 PM EDT | 10.9 | 2.65 | 54.1 | 16–44 |
| Oct 31, 9:15 PM EDT | 10.9 | 2.65 | 54.3 | 16–44 |
| Oct 31, 8:15 PM EDT | 10.9 | 2.65 | 54.5 | 16–44 |
| Oct 31, 7:15 PM EDT | 10.9 | 2.65 | 54.9 | 16–44 |
| Oct 31, 6:15 PM EDT | 10.9 | 2.65 | 55.2 | 16–44 |
| Oct 31, 5:15 PM EDT | 10.9 | 2.65 | 55.4 | 16–44 |
| Oct 31, 4:15 PM EDT | 10.9 | 2.65 | 55.6 | 16–44 |
| Oct 31, 3:15 PM EDT | 10.9 | 2.65 | 55.6 | 16–44 |
| Oct 31, 2:15 PM EDT | 10.9 | 2.65 | 55.2 | 16–44 |
| Oct 31, 1:15 PM EDT | 10.9 | 2.65 | 54.5 | 16–44 |
| Oct 31, 12:15 PM EDT | 11.2 | 2.66 | 54.1 | 16–44 |
| Oct 31, 11:15 AM EDT | 10.9 | 2.65 | 53.8 | 16–44 |
| Oct 31, 10:15 AM EDT | 10.5 | 2.64 | 53.2 | 16–44 |
| Oct 31, 9:15 AM EDT | 10.5 | 2.64 | 53.1 | 16–44 |
| Oct 31, 8:15 AM EDT | 10.5 | 2.64 | 53.2 | 16–44 |
| Oct 31, 7:15 AM EDT | 10.5 | 2.64 | 53.6 | 16–44 |
| Oct 31, 6:15 AM EDT | 10.5 | 2.64 | 53.8 | 16–44 |
| Oct 31, 5:15 AM EDT | 10.5 | 2.64 | 54 | 16–44 |
| Oct 31, 4:15 AM EDT | 10.5 | 2.64 | 54.3 | 16–44 |
| Oct 31, 3:15 AM EDT | 10.5 | 2.64 | 54.5 | 16–44 |
| Oct 31, 2:15 AM EDT | 10.5 | 2.64 | 54.9 | 16–44 |
| Oct 31, 1:15 AM EDT | 10.5 | 2.64 | 55 | 16–44 |
| Oct 31, 12:15 AM EDT | 10.5 | 2.64 | 55.4 | 16–44 |
| Oct 30, 11:15 PM EDT | 10.5 | 2.64 | 55.6 | 17–42 |
| Oct 30, 10:15 PM EDT | 10.5 | 2.64 | 55.9 | 17–42 |
| Oct 30, 9:15 PM EDT | 10.5 | 2.64 | 56.3 | 17–42 |
| Oct 30, 8:15 PM EDT | 10.5 | 2.64 | 56.5 | 17–42 |
| Oct 30, 7:15 PM EDT | 10.5 | 2.64 | 56.7 | 17–42 |
| Oct 30, 6:15 PM EDT | 10.5 | 2.64 | 56.8 | 17–42 |
| Oct 30, 5:15 PM EDT | 10.5 | 2.64 | 57.2 | 17–42 |
| Oct 30, 4:15 PM EDT | 10.5 | 2.64 | 57.6 | 17–42 |
| Oct 30, 3:15 PM EDT | 10.9 | 2.65 | 57.6 | 17–42 |
| Oct 30, 2:15 PM EDT | 10.5 | 2.64 | 57.2 | 17–42 |
| Oct 30, 1:15 PM EDT | 10.9 | 2.65 | 56.5 | 17–42 |
| Oct 30, 12:15 PM EDT | 10.9 | 2.65 | 55.9 | 17–42 |
| Oct 30, 11:15 AM EDT | 11.2 | 2.66 | 55.2 | 17–42 |
| Oct 30, 10:15 AM EDT | 11.2 | 2.66 | 54.9 | 17–42 |
| Oct 30, 9:15 AM EDT | 11.2 | 2.66 | 54.5 | 17–42 |
| Oct 30, 8:15 AM EDT | 10.9 | 2.65 | 54.7 | 17–42 |
| Oct 30, 7:15 AM EDT | 10.9 | 2.65 | 54.7 | 17–42 |
| Oct 30, 6:15 AM EDT | 10.9 | 2.65 | 54.9 | 17–42 |
| Oct 30, 5:15 AM EDT | 10.9 | 2.65 | 55 | 17–42 |
| Oct 30, 4:15 AM EDT | 11.2 | 2.66 | 55.2 | 17–42 |
| Oct 30, 3:15 AM EDT | 11.2 | 2.66 | 55.2 | 17–42 |
| Oct 30, 2:15 AM EDT | 10.9 | 2.65 | 55.4 | 17–42 |
| Oct 30, 1:15 AM EDT | 10.9 | 2.65 | 55.4 | 17–42 |
| Oct 30, 12:15 AM EDT | 10.9 | 2.65 | 55.6 | 17–42 |
| Oct 29, 11:15 PM EDT | 10.9 | 2.65 | 55.8 | 16–50 |
| Oct 29, 10:15 PM EDT | 11.2 | 2.66 | 55.9 | 16–50 |
Water temperature, last 7 days: 169 readings from Oct 29, 10:15 PM EDT to Nov 5, 9:15 PM EST; ranging 51.4 to 60.8 °F; latest 60.4 °F.
USGS provisional data may be revised. Source: USGS instantaneous values.
| Time | Water temperature (°F) |
|---|---|
| Nov 5, 9:15 PM EST | 60.4 |
| Nov 5, 8:15 PM EST | 60.4 |
| Nov 5, 7:15 PM EST | 60.4 |
| Nov 5, 6:15 PM EST | 60.6 |
| Nov 5, 5:15 PM EST | 60.6 |
| Nov 5, 4:15 PM EST | 60.8 |
| Nov 5, 3:15 PM EST | 60.8 |
| Nov 5, 2:15 PM EST | 60.6 |
| Nov 5, 1:15 PM EST | 60.1 |
| Nov 5, 12:15 PM EST | 59.5 |
| Nov 5, 11:15 AM EST | 59 |
| Nov 5, 10:15 AM EST | 58.5 |
| Nov 5, 9:15 AM EST | 58.1 |
| Nov 5, 8:15 AM EST | 57.6 |
| Nov 5, 7:15 AM EST | 57.2 |
| Nov 5, 6:15 AM EST | 57.2 |
| Nov 5, 5:15 AM EST | 56.8 |
| Nov 5, 4:15 AM EST | 56.7 |
| Nov 5, 3:15 AM EST | 56.5 |
| Nov 5, 2:15 AM EST | 56.3 |
| Nov 5, 1:15 AM EST | 56.1 |
| Nov 5, 12:15 AM EST | 56.1 |
| Nov 4, 11:15 PM EST | 55.9 |
| Nov 4, 10:15 PM EST | 55.9 |
| Nov 4, 9:15 PM EST | 55.9 |
| Nov 4, 8:15 PM EST | 55.9 |
| Nov 4, 7:15 PM EST | 56.1 |
| Nov 4, 6:15 PM EST | 56.1 |
| Nov 4, 5:15 PM EST | 56.3 |
| Nov 4, 4:15 PM EST | 56.7 |
| Nov 4, 3:15 PM EST | 56.8 |
| Nov 4, 2:15 PM EST | 56.7 |
| Nov 4, 1:15 PM EST | 56.1 |
| Nov 4, 12:15 PM EST | 55.2 |
| Nov 4, 11:15 AM EST | 54.5 |
| Nov 4, 10:15 AM EST | 54 |
| Nov 4, 9:15 AM EST | 53.4 |
| Nov 4, 8:15 AM EST | 53.1 |
| Nov 4, 7:15 AM EST | 53.1 |
| Nov 4, 6:15 AM EST | 53.2 |
| Nov 4, 5:15 AM EST | 53.2 |
| Nov 4, 4:15 AM EST | 53.4 |
| Nov 4, 3:15 AM EST | 53.4 |
| Nov 4, 2:15 AM EST | 53.4 |
| Nov 4, 1:15 AM EST | 53.4 |
| Nov 4, 12:15 AM EST | 53.4 |
| Nov 3, 11:15 PM EST | 53.6 |
| Nov 3, 10:15 PM EST | 53.6 |
| Nov 3, 9:15 PM EST | 54 |
| Nov 3, 8:15 PM EST | 54 |
| Nov 3, 7:15 PM EST | 54.1 |
| Nov 3, 6:15 PM EST | 54.3 |
| Nov 3, 5:15 PM EST | 54.3 |
| Nov 3, 4:15 PM EST | 54.7 |
| Nov 3, 3:15 PM EST | 54.9 |
| Nov 3, 2:15 PM EST | 54.9 |
| Nov 3, 1:15 PM EST | 54.3 |
| Nov 3, 12:15 PM EST | 53.4 |
| Nov 3, 11:15 AM EST | 52.7 |
| Nov 3, 10:15 AM EST | 52.2 |
| Nov 3, 9:15 AM EST | 51.6 |
| Nov 3, 8:15 AM EST | 51.4 |
| Nov 3, 7:15 AM EST | 51.4 |
| Nov 3, 6:15 AM EST | 51.4 |
| Nov 3, 5:15 AM EST | 51.6 |
| Nov 3, 4:15 AM EST | 51.8 |
| Nov 3, 3:15 AM EST | 52 |
| Nov 3, 2:15 AM EST | 52.2 |
| Nov 3, 1:15 AM EST | 52.3 |
| Nov 3, 12:15 AM EST | 52.5 |
| Nov 2, 11:15 PM EST | 52.7 |
| Nov 2, 10:15 PM EST | 52.9 |
| Nov 2, 9:15 PM EST | 53.1 |
| Nov 2, 8:15 PM EST | 53.4 |
| Nov 2, 7:15 PM EST | 53.6 |
| Nov 2, 6:15 PM EST | 54 |
| Nov 2, 5:15 PM EST | 54.3 |
| Nov 2, 4:15 PM EST | 54.3 |
| Nov 2, 3:15 PM EST | 54.3 |
| Nov 2, 2:15 PM EST | 54.3 |
| Nov 2, 1:15 PM EST | 54 |
| Nov 2, 12:15 PM EST | 53.4 |
| Nov 2, 11:15 AM EST | 53.1 |
| Nov 2, 10:15 AM EST | 52.7 |
| Nov 2, 9:15 AM EST | 52.2 |
| Nov 2, 8:15 AM EST | 51.8 |
| Nov 2, 7:15 AM EST | 51.8 |
| Nov 2, 6:15 AM EST | 51.8 |
| Nov 2, 5:15 AM EST | 52 |
| Nov 2, 4:15 AM EST | 52.2 |
| Nov 2, 3:15 AM EST | 52.3 |
| Nov 2, 2:15 AM EST | 52.5 |
| Nov 2, 1:15 AM EST | 52.7 |
| Nov 2, 12:15 AM EST | 52.9 |
| Nov 1, 11:15 PM EST | 53.2 |
| Nov 1, 10:15 PM EST | 53.4 |
| Nov 1, 9:15 PM EST | 53.6 |
| Nov 1, 8:15 PM EST | 54 |
| Nov 1, 7:15 PM EST | 54.1 |
| Nov 1, 6:15 PM EST | 54.5 |
| Nov 1, 5:15 PM EST | 54.7 |
| Nov 1, 4:15 PM EST | 54.9 |
| Nov 1, 3:15 PM EST | 55 |
| Nov 1, 2:15 PM EST | 55 |
| Nov 1, 1:15 PM EST | 54.9 |
| Nov 1, 12:15 PM EST | 54.3 |
| Nov 1, 11:15 AM EST | 54 |
| Nov 1, 10:15 AM EST | 53.4 |
| Nov 1, 9:15 AM EST | 53.1 |
| Nov 1, 8:15 AM EST | 52.9 |
| Nov 1, 7:15 AM EST | 52.9 |
| Nov 1, 6:15 AM EST | 53.1 |
| Nov 1, 5:15 AM EST | 53.2 |
| Nov 1, 4:15 AM EST | 53.4 |
| Nov 1, 3:15 AM EST | 53.6 |
| Nov 1, 2:15 AM EST | 53.6 |
| Nov 1, 1:15 AM EST | 53.6 |
| Nov 1, 1:15 AM EDT | 53.8 |
| Nov 1, 12:15 AM EDT | 53.8 |
| Oct 31, 11:15 PM EDT | 54 |
| Oct 31, 10:15 PM EDT | 54.1 |
| Oct 31, 9:15 PM EDT | 54.3 |
| Oct 31, 8:15 PM EDT | 54.5 |
| Oct 31, 7:15 PM EDT | 54.9 |
| Oct 31, 6:15 PM EDT | 55.2 |
| Oct 31, 5:15 PM EDT | 55.4 |
| Oct 31, 4:15 PM EDT | 55.6 |
| Oct 31, 3:15 PM EDT | 55.6 |
| Oct 31, 2:15 PM EDT | 55.2 |
| Oct 31, 1:15 PM EDT | 54.5 |
| Oct 31, 12:15 PM EDT | 54.1 |
| Oct 31, 11:15 AM EDT | 53.8 |
| Oct 31, 10:15 AM EDT | 53.2 |
| Oct 31, 9:15 AM EDT | 53.1 |
| Oct 31, 8:15 AM EDT | 53.2 |
| Oct 31, 7:15 AM EDT | 53.6 |
| Oct 31, 6:15 AM EDT | 53.8 |
| Oct 31, 5:15 AM EDT | 54 |
| Oct 31, 4:15 AM EDT | 54.3 |
| Oct 31, 3:15 AM EDT | 54.5 |
| Oct 31, 2:15 AM EDT | 54.9 |
| Oct 31, 1:15 AM EDT | 55 |
| Oct 31, 12:15 AM EDT | 55.4 |
| Oct 30, 11:15 PM EDT | 55.6 |
| Oct 30, 10:15 PM EDT | 55.9 |
| Oct 30, 9:15 PM EDT | 56.3 |
| Oct 30, 8:15 PM EDT | 56.5 |
| Oct 30, 7:15 PM EDT | 56.7 |
| Oct 30, 6:15 PM EDT | 56.8 |
| Oct 30, 5:15 PM EDT | 57.2 |
| Oct 30, 4:15 PM EDT | 57.6 |
| Oct 30, 3:15 PM EDT | 57.6 |
| Oct 30, 2:15 PM EDT | 57.2 |
| Oct 30, 1:15 PM EDT | 56.5 |
| Oct 30, 12:15 PM EDT | 55.9 |
| Oct 30, 11:15 AM EDT | 55.2 |
| Oct 30, 10:15 AM EDT | 54.9 |
| Oct 30, 9:15 AM EDT | 54.5 |
| Oct 30, 8:15 AM EDT | 54.7 |
| Oct 30, 7:15 AM EDT | 54.7 |
| Oct 30, 6:15 AM EDT | 54.9 |
| Oct 30, 5:15 AM EDT | 55 |
| Oct 30, 4:15 AM EDT | 55.2 |
| Oct 30, 3:15 AM EDT | 55.2 |
| Oct 30, 2:15 AM EDT | 55.4 |
| Oct 30, 1:15 AM EDT | 55.4 |
| Oct 30, 12:15 AM EDT | 55.6 |
| Oct 29, 11:15 PM EDT | 55.8 |
| Oct 29, 10:15 PM EDT | 55.9 |
Map of USGS gauge 01646000 and the river around it
Where DIFFICULT RUN NEAR GREAT FALLS, VA sits, with 1 other gauge on the same river.
Within Virginia DWR's comfort range. Water 60.4°F now; the highest in the last 24 hours was 60.8°F. Virginia DWR: trout “are most comfortable in highly oxygenated water that doesn’t exceed 68 degrees in temperature.” It also warns that “Trout become stressed in water temperatures in the mid- to upper-60s”: on warm days, “consider fishing early in the morning for a few hours and then quitting.”
Safe Practices for Summer Trout Fishing (7 June 2022)Normal for Nov 5: 18–44 ft³/s (middle half of 91 years of record). Now: 12.7 ft³/s, below normal.
Below normal for this date. 12.7 ft³/s is between the 10th and 25th percentiles of daily mean flow for Nov 5 at this gauge over 91 years of record (1936–2026): 10th 12, 25th 18, median 27, 75th 44, 90th 110 ft³/s.
Daily means on record for Nov 5: lowest 6.8 ft³/s, highest 540 ft³/s.
Classes as USGS labels them (hyswap: flow categories (WDFN_stats schema) (U.S. Geological Survey) ); percentiles from the USGS daily statistics (U.S. Geological Survey) (approved daily means; the reading is provisional and instantaneous).
Steady over 24 hours (+9.5% discharge). 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.
Species list not on file for this gauge. Check the Virginia Department of Wildlife Resources: Virginia daily trout stocking schedule · Virginia freshwater fishing regulations.
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)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)Dissolved oxygen 8.5 mg/L at Nov 5, 9:15 PM EST; 7-day range 8.5–11 mg/L
Enough oxygen for coldwater fish: 8.5 mg/L meets the 6.5 mg/L EPA sets for coldwater fish (other life stages; eggs and fry need a 8 mg/L minimum).
Quality Criteria for Water 1986 (“Gold Book”): dissolved oxygen, Table 1; pH (U.S. Environmental Protection Agency)pH 7.3 at Nov 5, 9:15 PM EST; 7-day range 7.3–7.5
Within EPA's freshwater range: pH 7.3 is within the 6.5–9 range EPA gives for freshwater aquatic life.
Quality Criteria for Water 1986 (“Gold Book”): dissolved oxygen, Table 1; pH (U.S. Environmental Protection Agency)Turbidity 1.3 FNU at Nov 5, 9:15 PM EST; 7-day range 1.2–2.1 FNU
Water clarity: Turbidity measures the relative clarity of water: higher means murkier. No agency publishes a fishing threshold for it; compare with this gauge's own recent readings.
Turbidity and Water (U.S. Geological Survey)Specific conductance 321 µS/cm at Nov 5, 9:15 PM EST; 7-day range 310–331 µS/cm
Dissolved ions: Specific conductance rises with the ions dissolved in the water. No fishing threshold is published for it; compare with this gauge's own recent readings.
Conductivity (Electrical Conductance) and Water (U.S. Geological Survey)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.
Below NWS action stage. The National Weather Service reports this gauge below its action stage. That is not a statement that wading is safe.
NWS observed 2.69 ft stage, 15 ft³/s at Nov 5, 8:15 PM EST (NWS gauge GFLV2; its stage datum can differ from the USGS gauge height).
Forecasts are not available. Only observed stages are available for this point.
Open the NWS gauge page · What the categories mean (National Weather Service)
Checked Nov 5, 9:39 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.