USGS · 06479525

BIG SIOUX RIVER

USGS · 06479525LIVE

Big Sioux R nr Castlewood, SD

HAMLIN COUNTY, SD44.7316°N, -97.0446°W Updated 48 min ago

FLOW RATE

41.9cfs

GAUGE HT

4.88ft

AIR TEMP

58°F

WIND

9mph WNW

FISH INDEX

69SCORE / 100

GREAT · 4 OF 5

1D 7D 30D 1YR

Flow Rate Historical Avg

MEDIAN FLOW RATE · 1 DAY

41.9cfs 75.7% vs avg

Optimal band: 36–48 cfs

PERIOD HIGH

44.1cfs

PERIOD LOW

38.7cfs

RUNNABLE

100%

last 1 day in band

Gauge Height

4.88ft

Precipitation History

SPONSORED

Weather Conditions

WEATHER CONDITIONS

TODAY

71°

53°

THU

73°

51°

FRI

78°

53°

SAT

83°

59°

SUN

104°

69°

MON

99°

75°

TUE

102°

63°

TIME

WED

NOW

THU

FRI

SAT

SUN

MON

TEMP

hourly forecast

68°

mild

68°

70°

71°

70°

69°

67°

63°

60°

58°

57°

55°

54°

53°

52°

51°

53°

58°

62°

66°

68°

70°

71°

72°

73°

72°

67°

64°

61°

58°

56°

55°

54°

53°

56°

62°

66°

68°

70°

71°

70°

77°

78°

77°

74°

73°

70°

68°

65°

63°

62°

60°

59°

60°

63°

67°

71°

75°

78°

80°

82°

83°

81°

80°

77°

74°

73°

72°

71°

69°

70°

71°

72°

73°

74°

76°

80°

84°

87°

90°

95°

98°

101°

104°

102°

97°

93°

90°

87°

85°

82°

81°

80°

79°

78°

77°

WIND

mph · gust · dir

14mph NW

G 19 mph

G19

G17

G18

G17

NNW

G17

G11

G10

NNW

WNW

G10

WNW

G10

G11

NNW

G13

G12

G10

NNW

WNW

G11

G10

G12

ESE

G12

ESE

G11

ESE

G11

ESE

G10

G15

G14

SSE

G15

G17

SSE

G19

G18

G19

G23

G26

G28

SSE

G29

SSE

G34

G33

G30

SSE

G31

SSE

G32

G33

SSE

G31

G32

SSE

G34

SSE

G34

SSE

G30

SSE

G28

SSE

G28

SSE

G28

SSE

G27

SSE

G26

SSE

G26

SSE

G29

SSE

G28

G29

G33

G35

G37

SSE

G38

SSE

G38

G34

G28

G26

G28

G25

SSE

G23

SSE

G23

SSE

G26

G24

SSW

G25

SSW

G25

SSW

G23

SSW

G24

SSW

G28

G33

G37

G39

SSE

G39

SSE

G40

SSE

G39

SSE

G39

SSE

G37

SSE

PRECIP

chance %

10%

21%

29%

22%

18%

10%

38%

CLOUDS

cover %

33%

few

33%

36%

27%

29%

38%

100%

85%

78%

18%

26%

100%

20%

74%

62%

100%

72%

100%

77%

100%

20%

100%

19%

47%

100%

78%

70%

100%

95%

100%

23%

100%

74%

100%

30%

100%

67%

15%

41%

56%

92%

77%

100%

89%

100%

78%

100%

76%

31%

PRESSURE

hPa · trend

959

TemperatureWind / GustsPrecipitationCloud coverPressure

Nowscroll →

FISH INDEX

Temperature

Ideal

Wind

Light

Pressure

Rising — Slow

Moon Phase

Average

DAYLIGHT

SUNRISE

05:43 AM

SUNSET

09:17 PM

15H 34M OF DAYLIGHT8H 44M REMAINING

MOON PHASE

Waxing Gibbous

69% illuminated

Station Location

44.7316, -97.0446

Loading map…

DATA · USGS · NOAA · NWSUPDATED 2026-06-24 12:33 UTC

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