USGS · 06479525

BIG SIOUX RIVER

USGS · 06479525LIVE

Big Sioux R nr Castlewood, SD

HAMLIN COUNTY, SD44.7316°N, -97.0446°W Updated 13 hr ago

FLOW RATE

41cfs

AIR TEMP

62°F

WIND

12mph NW

FISH INDEX

69SCORE / 100

GREAT · 4 OF 5

1D 7D 30D 1YR

Flow Rate Historical Avg

MEDIAN FLOW RATE · 7 DAY

41cfs 66.0% vs avg

Optimal band: 42–56 cfs

PERIOD HIGH

65cfs

PERIOD LOW

41cfs

RUNNABLE

63%

last 7 day in band

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

70°

mild

70°

71°

70°

68°

64°

61°

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 18 mph

G18

G17

G18

G10

G11

NNW

G14

NNW

G13

NNW

WNW

G10

WNW

G10

G11

NNW

G13

G12

G10

NNW

WNW

G11

G10

G12

ESE

G13

ESE

G12

ESE

G13

ESE

G15

G14

G15

G14

G13

G12

G13

SSE

G16

G17

SSE

G17

G19

G22

G23

G26

SSE

G28

SSE

G31

G35

G33

SSE

G32

SSE

G31

G32

SSE

G33

SSE

G32

SSE

G28

SSE

G27

SSE

G26

SSE

G27

SSE

G27

SSE

G28

SSE

G27

SSE

G27

SSE

G26

SSE

G25

G31

G35

G33

G31

SSE

G32

SSE

G35

G32

G30

G31

G29

G27

SSE

G27

SSE

G26

SSE

G26

G25

SSW

G26

SSW

G26

SSW

G27

SSW

G26

SSW

G32

G34

G36

G38

G39

G36

SSE

G36

SSE

G36

SSE

G36

SSE

G36

SSE

G36

SSE

G35

SSE

PRECIP

chance %

10%

21%

29%

22%

18%

10%

38%

CLOUDS

cover %

37%

few

37%

40%

35%

16%

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

Moderate

Pressure

Stable

Moon Phase

Average

DAYLIGHT

SUNRISE

05:43 AM

SUNSET

09:17 PM

15H 34M OF DAYLIGHT7H 25M REMAINING

MOON PHASE

Waxing Gibbous

70% illuminated

Station Location

44.7316, -97.0446

Loading map…

DATA · USGS · NOAA · NWSUPDATED 2026-06-24 13:52 UTC

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