USGS · 01661500

ST MARYS RIVER

USGS · 01661500LIVE

ST MARYS RIVER AT GREAT MILLS, MD

MARYLAND38.2418°N, -76.5037°W Updated 48 min ago

FLOW RATE

9cfs

AIR TEMP

80°F

WIND

5mph NNE

FISH INDEX

56SCORE / 100

GOOD · 3 OF 5

1D 7D 30D 1YR

Flow Rate Historical Avg

MEDIAN FLOW RATE · 1 YEAR

9cfs 57.3% vs avg

Optimal band: 5–7 cfs

PERIOD HIGH

270cfs

PERIOD LOW

1cfs

RUNNABLE

28%

last 1 year in band

Precipitation History

Your History · ST MARYS RIVER AT GREAT MILLS, MD

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Weather Conditions

WEATHER CONDITIONS

TODAY

86°

73°

WED

84°

71°

THU

89°

73°

FRI

96°

71°

SAT

87°

71°

SUN

86°

71°

MON

83°

70°

TIME

WED

NOW

THU

FRI

SAT

SUN

TEMP

hourly forecast

75°

mild

75°

73°

72°

71°

73°

74°

83°

82°

84°

83°

82°

80°

78°

76°

75°

74°

73°

75°

77°

79°

81°

82°

83°

89°

88°

83°

87°

78°

81°

80°

78°

77°

75°

74°

73°

72°

71°

72°

75°

80°

86°

90°

91°

92°

94°

96°

93°

92°

84°

77°

72°

73°

72°

71°

72°

71°

74°

79°

82°

84°

87°

86°

84°

82°

81°

77°

74°

73°

72°

71°

72°

75°

76°

77°

83°

85°

86°

85°

82°

79°

78°

77°

WIND

mph · gust · dir

7mph ENE

G 15 mph

G15

ENE

G20

ENE

G18

ENE

G17

ENE

G15

G14

G13

G12

G11

ENE

NNW

SSE

G11

SSE

G12

SSE

G14

SSE

G14

SSE

G14

G16

SSW

G15

SSW

G12

G10

G11

G10

G11

G13

SSE

G13

G11

SSW

SSE

G15

WNW

NNW

G10

WNW

G10

WNW

G13

WNW

G10

WNW

WSW

G10

WSW

G13

WSW

G16

G12

G13

NNW

G15

ESE

G35

G33

G30

WNW

G29

NNW

G30

NNW

G29

NNW

G29

G30

G31

NNW

G30

NNW

G24

G20

G17

G15

NNE

G13

NNE

G13

NNE

G13

NNE

G11

NNE

G13

NNE

G15

NNE

G13

NNE

G12

ENE

ESE

G11

SSE

G10

G11

NNW

NNE

ENE

ESE

G10

G12

G15

G17

ESE

PRECIP

chance %

29%

21%

29%

27%

26%

25%

10%

13%

20%

63%

83%

42%

37%

38%

21%

36%

19%

16%

10%

CLOUDS

cover %

100%

overcast

100%

97%

99%

100%

49%

68%

36%

15%

100%

77%

92%

61%

37%

100%

86%

100%

77%

40%

75%

15%

24%

100%

15%

100%

59%

19%

17%

13%

12%

100%

69%

100%

49%

100%

68%

100%

98%

33%

39%

18%

14%

100%

80%

100%

92%

100%

42%

100%

PRESSURE

hPa · trend

1013

TemperatureWind / GustsPrecipitationCloud coverPressure

Nowscroll →

FISH INDEX

Temperature

Too Hot

Wind

Light

Pressure

Rising — Slow

Moon Phase

Good

DAYLIGHT

SUNRISE

05:49 AM

SUNSET

08:32 PM

14H 43M OF DAYLIGHT

MOON PHASE

Last Quarter

43% illuminated

Station Location

38.2418, -76.5037

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DATA · USGS · NOAA · NWSUPDATED 2026-07-08 00:00 UTC

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