USGS · 01646000

DIFFICULT RUN

USGS · 01646000LIVE

DIFFICULT RUN NEAR GREAT FALLS, VA

RESTON, VA38.9759°N, -77.2458°W Updated 9 hr ago

FLOW RATE

12cfs

AIR TEMP

72°F

WIND

3mph SW

FISH INDEX

75SCORE / 100

GREAT · 4 OF 5

1D 7D 30D 1YR

Flow Rate Historical Avg

MEDIAN FLOW RATE · 7 DAY

12cfs 43.0% vs avg

Optimal band: 10–14 cfs

PERIOD HIGH

117cfs

PERIOD LOW

7cfs

RUNNABLE

25%

last 7 day in band

Precipitation History

Your History · DIFFICULT RUN NEAR GREAT FALLS, VA

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Weather Conditions

WEATHER CONDITIONS

TODAY

82°

72°

SUN

84°

70°

MON

87°

70°

TUE

93°

70°

WED

100°

72°

THU

102°

77°

FRI

100°

74°

TIME

SAT

NOW

SUN

MON

TUE

WED

THU

TEMP

hourly forecast

77°

mild

77°

76°

78°

81°

80°

82°

81°

80°

78°

76°

74°

73°

72°

71°

70°

72°

74°

76°

77°

80°

81°

82°

83°

84°

82°

79°

78°

76°

74°

72°

71°

70°

71°

73°

76°

79°

80°

82°

83°

85°

86°

87°

86°

84°

79°

77°

76°

75°

74°

73°

72°

71°

70°

72°

75°

78°

81°

84°

87°

89°

91°

92°

93°

92°

89°

85°

80°

78°

77°

76°

75°

74°

73°

72°

74°

77°

81°

85°

89°

93°

96°

98°

99°

100°

97°

92°

89°

84°

81°

79°

78°

77°

WIND

mph · gust · dir

4mph SSW

G 8 mph

SSW

G10

SSW

G10

G11

SSW

G11

G12

G11

SSW

ESE

ENE

ESE

ENE

ESE

ENE

NNE

G10

NNE

G16

NNE

G15

NNE

G17

G14

ENE

G15

ENE

G11

WSW

ENE

NNW

NNE

ENE

ESE

G12

ESE

G14

G15

SSE

G15

SSE

G14

SSE

G12

G10

SSE

G12

SSE

G17

SSE

G22

SSE

G25

SSE

G26

G25

G26

SSW

G27

SSW

G26

SSW

G22

SSW

G16

SSW

G12

SSW

WSW

WNW

ENE

ESE

SSW

G12

G14

WSW

G13

WSW

PRECIP

chance %

19%

16%

15%

14%

15%

23%

34%

30%

28%

25%

18%

21%

11%

10%

12%

16%

28%

32%

50%

13%

CLOUDS

cover %

100%

overcast

100%

74%

27%

51%

54%

96%

100%

91%

100%

94%

12%

100%

77%

33%

18%

10%

100%

36%

100%

84%

100%

41%

51%

42%

34%

22%

35%

28%

29%

11%

10%

11%

10%

17%

57%

59%

73%

26%

32%

93%

10%

18%

11%

10%

PRESSURE

hPa · trend

1009

TemperatureWind / GustsPrecipitationCloud coverPressure

Nowscroll →

FISH INDEX

Temperature

Warm

Wind

Calm

Pressure

Stable

Moon Phase

Average

DAYLIGHT

SUNRISE

05:45 AM

SUNSET

08:38 PM

14H 53M OF DAYLIGHT11H 7M REMAINING

MOON PHASE

Waxing Gibbous

92% illuminated

Station Location

38.9759, -77.2458

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DATA · USGS · NOAA · NWSUPDATED 2026-06-27 09:31 UTC

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