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Live/Water/Maryland/Potomac River at Little Falls

Potomac River at Little Falls

A gauge on the Potomac River in Montgomery County, Maryland. Its stage was 4.25 ft as of Oct 16, 12:50 AM EDT.

Gauge BRKM2Montgomery County, MarylandEvery gauge in Maryland

Stage now
4.25 ftreported Oct 16, 12:50 AM EDT
24 hour change
Fell 0.64 ftsince Oct 15, 12:50 AM
Elevation
82 ftabove sea level
County
Montgomery County
Position
38.9494° N, 77.1278° W
Record since
2010

Water level

Potomac River at Little Falls

Stage is the height of the water's surface above the gauge's own fixed zero, in feet, not the depth of the water. Every point drawn is a reading the gauge sent, at the time it sent it.

Water level, 24 hours at Potomac River at Little Falls: the water from 4.25 to 4.88 feet of stage, the latest 4.25 feet.WATER LEVEL, 24 HOURSFTHIGH 4.88 FT, OCT 15, 1:10 AM · LOW 4.25 FT, OCT 16, 12:25 AM4.24.44.64.85.03 AM6 AM9 AM12 PM3 PM6 PM9 PMOct 164.25
Latest
4.25 ftOct 16, 12:50 AM
Highest
4.88 ftOct 15, 1:10 AM
Lowest
4.25 ftOct 16, 12:25 AM
Range
0.63 fthighest less lowest
Change
Fell 0.63 ftsince Oct 15, 1:10 AM
Readings
285
The readings these charts were drawn from, as a table
TimeStage ft
Oct 16, 12:50 AM4.25
Oct 16, 12:45 AM4.25
Oct 16, 12:40 AM4.25
Oct 16, 12:35 AM4.25
Oct 16, 12:30 AM4.25
Oct 16, 12:25 AM4.25
Oct 16, 12:20 AM4.26
Oct 16, 12:15 AM4.26
Oct 16, 12:10 AM4.26
Oct 16, 12:05 AM4.26
Oct 16, 12:00 AM4.26
Oct 15, 11:55 PM4.27
Oct 15, 11:50 PM4.27
Oct 15, 11:45 PM4.27
Oct 15, 11:40 PM4.28
Oct 15, 11:35 PM4.28
Oct 15, 11:30 PM4.28
Oct 15, 11:25 PM4.28
Oct 15, 11:20 PM4.28
Oct 15, 11:15 PM4.29
Oct 15, 11:10 PM4.29
Oct 15, 11:05 PM4.29
Oct 15, 11:00 PM4.29
Oct 15, 10:55 PM4.29
Oct 15, 10:50 PM4.30
Oct 15, 10:45 PM4.29
Oct 15, 10:40 PM4.30
Oct 15, 10:35 PM4.30
Oct 15, 10:30 PM4.30
Oct 15, 10:25 PM4.30
Oct 15, 10:20 PM4.31
Oct 15, 10:15 PM4.31
Oct 15, 10:10 PM4.31
Oct 15, 10:05 PM4.32
Oct 15, 10:00 PM4.31
Oct 15, 9:55 PM4.32
Oct 15, 9:50 PM4.32
Oct 15, 9:45 PM4.32
Oct 15, 9:40 PM4.32
Oct 15, 9:35 PM4.32
Oct 15, 9:30 PM4.33
Oct 15, 9:25 PM4.32
Oct 15, 9:20 PM4.33
Oct 15, 9:15 PM4.33
Oct 15, 9:10 PM4.33
Oct 15, 9:05 PM4.34
Oct 15, 9:00 PM4.34
Oct 15, 8:55 PM4.34
Oct 15, 8:50 PM4.34
Oct 15, 8:45 PM4.34
Oct 15, 8:40 PM4.34
Oct 15, 8:35 PM4.34
Oct 15, 8:30 PM4.35
Oct 15, 8:25 PM4.35
Oct 15, 8:20 PM4.35
Oct 15, 8:15 PM4.35
Oct 15, 8:10 PM4.36
Oct 15, 8:05 PM4.36
Oct 15, 8:00 PM4.36
Oct 15, 7:55 PM4.37
Oct 15, 7:50 PM4.37
Oct 15, 7:45 PM4.37
Oct 15, 7:40 PM4.37
Oct 15, 7:35 PM4.37
Oct 15, 7:30 PM4.37
Oct 15, 7:25 PM4.37
Oct 15, 7:20 PM4.37
Oct 15, 7:15 PM4.38
Oct 15, 7:10 PM4.38
Oct 15, 7:05 PM4.38
Oct 15, 7:00 PM4.38
Oct 15, 6:55 PM4.38
Oct 15, 6:50 PM4.38
Oct 15, 6:45 PM4.38
Oct 15, 6:40 PM4.39
Oct 15, 6:35 PM4.39
Oct 15, 6:30 PM4.39
Oct 15, 6:25 PM4.39
Oct 15, 6:20 PM4.40
Oct 15, 6:15 PM4.40
Oct 15, 6:10 PM4.40
Oct 15, 6:05 PM4.40
Oct 15, 6:00 PM4.41
Oct 15, 5:55 PM4.41
Oct 15, 5:50 PM4.41
Oct 15, 5:45 PM4.41
Oct 15, 5:40 PM4.41
Oct 15, 5:35 PM4.41
Oct 15, 5:30 PM4.42
Oct 15, 5:25 PM4.42
Oct 15, 5:20 PM4.42
Oct 15, 5:15 PM4.42
Oct 15, 5:10 PM4.43
Oct 15, 5:05 PM4.43
Oct 15, 5:00 PM4.43
Oct 15, 4:55 PM4.43
Oct 15, 4:50 PM4.43
Oct 15, 4:45 PM4.44
Oct 15, 4:40 PM4.44
Oct 15, 4:35 PM4.44
Oct 15, 4:30 PM4.44
Oct 15, 4:25 PM4.45
Oct 15, 4:20 PM4.45
Oct 15, 4:15 PM4.45
Oct 15, 4:10 PM4.46
Oct 15, 4:05 PM4.46
Oct 15, 4:00 PM4.46
Oct 15, 3:55 PM4.46
Oct 15, 3:50 PM4.47
Oct 15, 3:45 PM4.47
Oct 15, 3:40 PM4.47
Oct 15, 3:35 PM4.47
Oct 15, 3:30 PM4.47
Oct 15, 3:25 PM4.47
Oct 15, 3:20 PM4.47
Oct 15, 3:15 PM4.48
Oct 15, 3:10 PM4.48
Oct 15, 3:05 PM4.48
Oct 15, 3:00 PM4.48
Oct 15, 2:55 PM4.48
Oct 15, 2:50 PM4.49
Oct 15, 2:45 PM4.49
Oct 15, 2:40 PM4.49
Oct 15, 2:35 PM4.50
Oct 15, 2:30 PM4.50
Oct 15, 2:25 PM4.50
Oct 15, 2:20 PM4.50
Oct 15, 2:15 PM4.51
Oct 15, 2:10 PM4.51
Oct 15, 2:05 PM4.51
Oct 15, 2:00 PM4.51
Oct 15, 1:55 PM4.51
Oct 15, 1:50 PM4.51
Oct 15, 1:45 PM4.52
Oct 15, 1:40 PM4.52
Oct 15, 1:35 PM4.52
Oct 15, 1:30 PM4.52
Oct 15, 1:25 PM4.53
Oct 15, 1:20 PM4.53
Oct 15, 1:15 PM4.53
Oct 15, 1:10 PM4.54
Oct 15, 1:05 PM4.54
Oct 15, 1:00 PM4.54
Oct 15, 12:55 PM4.54
Oct 15, 12:50 PM4.54
Oct 15, 12:45 PM4.55
Oct 15, 12:40 PM4.55
Oct 15, 12:35 PM4.56
Oct 15, 12:30 PM4.56
Oct 15, 12:25 PM4.56
Oct 15, 12:20 PM4.56
Oct 15, 12:15 PM4.57
Oct 15, 12:10 PM4.57
Oct 15, 12:05 PM4.57
Oct 15, 12:00 PM4.57
Oct 15, 11:55 AM4.57
Oct 15, 11:50 AM4.57
Oct 15, 11:45 AM4.58
Oct 15, 11:40 AM4.59
Oct 15, 11:35 AM4.58
Oct 15, 11:30 AM4.58
Oct 15, 11:25 AM4.59
Oct 15, 11:20 AM4.59
Oct 15, 11:15 AM4.59
Oct 15, 11:10 AM4.59
Oct 15, 11:05 AM4.60
Oct 15, 11:00 AM4.60
Oct 15, 10:55 AM4.60
Oct 15, 10:50 AM4.60
Oct 15, 10:45 AM4.60
Oct 15, 10:40 AM4.60
Oct 15, 10:35 AM4.61
Oct 15, 10:30 AM4.61
Oct 15, 10:25 AM4.61
Oct 15, 10:20 AM4.61
Oct 15, 10:15 AM4.62
Oct 15, 10:10 AM4.62
Oct 15, 10:05 AM4.62
Oct 15, 10:00 AM4.62
Oct 15, 9:55 AM4.62
Oct 15, 9:50 AM4.62
Oct 15, 9:45 AM4.63
Oct 15, 9:40 AM4.63
Oct 15, 9:35 AM4.63
Oct 15, 9:30 AM4.63
Oct 15, 9:25 AM4.64
Oct 15, 9:20 AM4.64
Oct 15, 9:15 AM4.64
Oct 15, 9:10 AM4.63
Oct 15, 9:05 AM4.64
Oct 15, 9:00 AM4.64
Oct 15, 8:55 AM4.64
Oct 15, 8:50 AM4.64
Oct 15, 8:45 AM4.65
Oct 15, 8:40 AM4.64
Oct 15, 8:35 AM4.65
Oct 15, 8:30 AM4.65
Oct 15, 8:25 AM4.65
Oct 15, 8:20 AM4.66
Oct 15, 8:15 AM4.66
Oct 15, 8:10 AM4.66
Oct 15, 8:05 AM4.66
Oct 15, 8:00 AM4.67
Oct 15, 7:55 AM4.67
Oct 15, 7:50 AM4.67
Oct 15, 7:45 AM4.68
Oct 15, 7:40 AM4.68
Oct 15, 7:35 AM4.68
Oct 15, 7:30 AM4.68
Oct 15, 7:25 AM4.69
Oct 15, 7:20 AM4.69
Oct 15, 7:15 AM4.70
Oct 15, 7:10 AM4.70
Oct 15, 7:05 AM4.70
Oct 15, 7:00 AM4.70
Oct 15, 6:55 AM4.71
Oct 15, 6:50 AM4.71
Oct 15, 6:45 AM4.72
Oct 15, 6:40 AM4.71
Oct 15, 6:35 AM4.72
Oct 15, 6:30 AM4.72
Oct 15, 6:25 AM4.72
Oct 15, 6:20 AM4.73
Oct 15, 6:15 AM4.73
Oct 15, 6:10 AM4.73
Oct 15, 6:05 AM4.73
Oct 15, 6:00 AM4.73
Oct 15, 5:55 AM4.74
Oct 15, 5:50 AM4.75
Oct 15, 5:45 AM4.74
Oct 15, 5:40 AM4.75
Oct 15, 5:35 AM4.76
Oct 15, 5:30 AM4.76
Oct 15, 5:25 AM4.76
Oct 15, 5:20 AM4.77
Oct 15, 5:15 AM4.77
Oct 15, 5:10 AM4.77
Oct 15, 5:05 AM4.77
Oct 15, 5:00 AM4.78
Oct 15, 4:55 AM4.78
Oct 15, 4:50 AM4.79
Oct 15, 4:45 AM4.79
Oct 15, 4:40 AM4.79
Oct 15, 4:35 AM4.80
Oct 15, 4:30 AM4.79
Oct 15, 4:25 AM4.80
Oct 15, 4:20 AM4.80
Oct 15, 4:15 AM4.81
Oct 15, 4:10 AM4.81
Oct 15, 4:05 AM4.81
Oct 15, 4:00 AM4.81
Oct 15, 3:55 AM4.81
Oct 15, 3:50 AM4.82
Oct 15, 3:45 AM4.82
Oct 15, 3:40 AM4.82
Oct 15, 3:35 AM4.82
Oct 15, 3:30 AM4.82
Oct 15, 3:25 AM4.83
Oct 15, 3:20 AM4.83
Oct 15, 3:15 AM4.84
Oct 15, 3:10 AM4.84
Oct 15, 3:05 AM4.83
Oct 15, 3:00 AM4.84
Oct 15, 2:55 AM4.82
Oct 15, 2:50 AM4.83
Oct 15, 2:45 AM4.83
Oct 15, 2:40 AM4.83
Oct 15, 2:35 AM4.84
Oct 15, 2:30 AM4.84
Oct 15, 2:25 AM4.85
Oct 15, 2:20 AM4.84
Oct 15, 2:15 AM4.84
Oct 15, 2:10 AM4.85
Oct 15, 2:05 AM4.85
Oct 15, 2:00 AM4.85
Oct 15, 1:55 AM4.86
Oct 15, 1:50 AM4.86
Oct 15, 1:45 AM4.86
Oct 15, 1:40 AM4.87
Oct 15, 1:35 AM4.87
Oct 15, 1:30 AM4.87
Oct 15, 1:25 AM4.87
Oct 15, 1:20 AM4.87
Oct 15, 1:15 AM4.88
Oct 15, 1:10 AM4.88
Water level, 7 days at Potomac River at Little Falls: the water from 2.65 to 5.26 feet of stage, the latest 4.25 feet.WATER LEVEL, 7 DAYSFTHIGH 5.26 FT, OCT 14, 10:45 AM · LOW 2.65 FT, OCT 9, 7:40 AM23456Sat 10Sun 11Mon 12Tue 13Wed 14Thu 15Fri 164.25
Latest
4.25 ftOct 16, 12:50 AM
Highest
5.26 ftOct 14, 10:45 AM
Lowest
2.65 ftOct 9, 7:40 AM
Range
2.61 fthighest less lowest
Change
Rose 1.53 ftsince Oct 9, 1:10 AM
Readings
2,013
The readings these charts were drawn from, as a table
TimeStage ft
Oct 16, 12:50 AM4.25
Oct 15, 11:55 PM4.27
Oct 15, 10:55 PM4.29
Oct 15, 9:55 PM4.32
Oct 15, 8:55 PM4.34
Oct 15, 7:55 PM4.37
Oct 15, 6:55 PM4.38
Oct 15, 5:55 PM4.41
Oct 15, 4:55 PM4.43
Oct 15, 3:55 PM4.46
Oct 15, 2:55 PM4.48
Oct 15, 1:55 PM4.51
Oct 15, 12:55 PM4.54
Oct 15, 11:55 AM4.57
Oct 15, 10:55 AM4.60
Oct 15, 9:55 AM4.62
Oct 15, 8:55 AM4.64
Oct 15, 7:55 AM4.67
Oct 15, 6:55 AM4.71
Oct 15, 5:55 AM4.74
Oct 15, 4:55 AM4.78
Oct 15, 3:55 AM4.81
Oct 15, 2:55 AM4.82
Oct 15, 1:55 AM4.86
Oct 15, 12:55 AM4.88
Oct 14, 11:55 PM4.93
Oct 14, 10:55 PM4.96
Oct 14, 9:55 PM5.00
Oct 14, 8:55 PM5.03
Oct 14, 7:55 PM5.08
Oct 14, 6:55 PM5.11
Oct 14, 5:55 PM5.14
Oct 14, 4:55 PM5.15
Oct 14, 3:55 PM5.17
Oct 14, 2:55 PM5.19
Oct 14, 1:55 PM5.21
Oct 14, 12:55 PM5.22
Oct 14, 11:55 AM5.26
Oct 14, 10:55 AM5.26
Oct 14, 9:55 AM5.23
Oct 14, 8:55 AM5.25
Oct 14, 7:55 AM5.22
Oct 14, 6:55 AM5.16
Oct 14, 5:55 AM5.11
Oct 14, 4:55 AM5.03
Oct 14, 3:55 AM4.93
Oct 14, 2:55 AM4.81
Oct 14, 1:55 AM4.70
Oct 14, 12:55 AM4.59
Oct 13, 11:55 PM4.50
Oct 13, 10:55 PM4.45
Oct 13, 9:55 PM4.41
Oct 13, 8:55 PM4.39
Oct 13, 7:55 PM4.38
Oct 13, 6:55 PM4.36
Oct 13, 5:55 PM4.34
Oct 13, 4:55 PM4.32
Oct 13, 3:55 PM4.29
Oct 13, 2:55 PM4.27
Oct 13, 1:55 PM4.25
Oct 13, 12:55 PM4.21
Oct 13, 11:55 AM4.16
Oct 13, 10:55 AM4.14
Oct 13, 9:55 AM4.12
Oct 13, 8:55 AM4.11
Oct 13, 7:55 AM4.09
Oct 13, 6:55 AM4.08
Oct 13, 5:55 AM4.08
Oct 13, 4:55 AM4.08
Oct 13, 3:55 AM4.08
Oct 13, 2:55 AM4.08
Oct 13, 1:55 AM4.09
Oct 13, 12:55 AM4.08
Oct 12, 11:55 PM4.10
Oct 12, 10:55 PM4.12
Oct 12, 9:55 PM4.12
Oct 12, 8:55 PM4.13
Oct 12, 7:55 PM4.13
Oct 12, 6:55 PM4.12
Oct 12, 5:55 PM4.13
Oct 12, 4:55 PM4.13
Oct 12, 3:55 PM4.11
Oct 12, 2:55 PM4.08
Oct 12, 1:55 PM4.04
Oct 12, 12:55 PM4.00
Oct 12, 11:55 AM3.96
Oct 12, 10:55 AM3.91
Oct 12, 9:55 AM3.86
Oct 12, 8:55 AM3.82
Oct 12, 7:55 AM3.80
Oct 12, 6:55 AM3.77
Oct 12, 5:55 AM3.74
Oct 12, 4:55 AM3.73
Oct 12, 3:55 AM3.72
Oct 12, 2:55 AM3.69
Oct 12, 1:55 AM3.67
Oct 12, 12:55 AM3.63
Oct 11, 11:55 PM3.60
Oct 11, 10:55 PM3.55
Oct 11, 9:55 PM3.52
Oct 11, 8:55 PM3.48
Oct 11, 7:55 PM3.47
Oct 11, 6:55 PM3.48
Oct 11, 5:55 PM3.45
Oct 11, 4:55 PM3.41
Oct 11, 3:55 PM3.34
Oct 11, 2:55 PM3.26
Oct 11, 1:55 PM3.22
Oct 11, 12:55 PM3.19
Oct 11, 11:55 AM3.08
Oct 11, 10:55 AM2.90
Oct 11, 9:55 AM2.80
Oct 11, 8:55 AM2.75
Oct 11, 7:55 AM2.72
Oct 11, 6:55 AM2.71
Oct 11, 5:55 AM2.69
Oct 11, 4:55 AM2.69
Oct 11, 3:55 AM2.69
Oct 11, 2:55 AM2.68
Oct 11, 1:55 AM2.69
Oct 11, 12:55 AM2.71
Oct 10, 11:55 PM2.73
Oct 10, 10:55 PM2.73
Oct 10, 9:55 PM2.73
Oct 10, 8:55 PM2.71
Oct 10, 7:55 PM2.71
Oct 10, 6:55 PM2.71
Oct 10, 5:55 PM2.71
Oct 10, 4:55 PM2.71
Oct 10, 3:55 PM2.71
Oct 10, 2:55 PM2.70
Oct 10, 1:55 PM2.70
Oct 10, 12:55 PM2.73
Oct 10, 11:55 AM2.72
Oct 10, 10:55 AM2.72
Oct 10, 9:55 AM2.71
Oct 10, 8:55 AM2.68
Oct 10, 7:55 AM2.67
Oct 10, 6:55 AM2.66
Oct 10, 5:55 AM2.68
Oct 10, 4:55 AM2.68
Oct 10, 3:55 AM2.68
Oct 10, 2:55 AM2.68
Oct 10, 1:55 AM2.69
Oct 10, 12:55 AM2.70
Oct 9, 11:55 PM2.70
Oct 9, 10:55 PM2.69
Oct 9, 9:55 PM2.69
Oct 9, 8:55 PM2.70
Oct 9, 7:55 PM2.71
Oct 9, 6:55 PM2.71
Oct 9, 5:55 PM2.73
Oct 9, 4:55 PM2.73
Oct 9, 3:55 PM2.70
Oct 9, 2:55 PM2.67
Oct 9, 1:55 PM2.66
Oct 9, 12:55 PM2.67
Oct 9, 11:55 AM2.66
Oct 9, 10:55 AM2.65
Oct 9, 9:55 AM2.65
Oct 9, 8:55 AM2.65
Oct 9, 7:55 AM2.65
Oct 9, 6:55 AM2.66
Oct 9, 5:55 AM2.67
Oct 9, 4:55 AM2.68
Oct 9, 3:55 AM2.69
Oct 9, 2:55 AM2.70
Oct 9, 1:55 AM2.71
Water level, 30 days at Potomac River at Little Falls: the water from 2.64 to 5.26 feet of stage, the latest 4.25 feet.WATER LEVEL, 30 DAYSFTHIGH 5.26 FT, OCT 14, 10:45 AM · LOW 2.64 FT, SEP 17, 8:00 AM23456Sep 16Sep 21Sep 26Oct 1Oct 6Oct 114.25
Latest
4.25 ftOct 16, 12:50 AM
Highest
5.26 ftOct 14, 10:45 AM
Lowest
2.64 ftSep 17, 8:00 AM
Range
2.62 fthighest less lowest
Change
Rose 1.55 ftsince Sep 16, 1:15 AM
Readings
5,468
The readings these charts were drawn from, as a table
DayHigh ftLow ftAverage ftLast ftReadings
Oct 164.264.254.254.2511
Oct 154.924.274.584.27288
Oct 145.264.515.064.93288
Oct 134.514.074.224.50288
Oct 124.143.613.934.10288
Oct 113.602.683.073.60288
Oct 102.742.662.702.73288
Oct 92.732.652.692.70288
Oct 82.762.682.712.72288
Oct 72.782.702.732.72276
Oct 62.772.732.752.75288
Oct 52.812.742.782.75288
Oct 42.872.802.852.81276
Oct 32.912.842.882.85288
Oct 22.912.832.872.84194
Oct 13.012.902.962.9199
Sep 303.032.963.003.0098
Sep 293.133.023.093.0296
Sep 283.273.133.173.1399
Sep 273.323.253.283.2899
Sep 263.273.093.143.2797
Sep 253.153.093.133.1498
Sep 243.123.063.093.1299
Sep 233.203.103.173.1198
Sep 223.122.752.953.1292
Sep 212.842.652.712.7999
Sep 202.702.652.672.6987
Sep 192.692.662.672.6693
Sep 182.692.642.662.6899
Sep 172.672.642.662.6699
Sep 162.702.672.692.6791

How it reports

Schedule
every houron the hour's :50
Reports received, 24 hours
24 of 24100% of its schedule, 27 reports in all
Reports received, 7 days
168 of 168100% of its schedule, 191 reports in all
Longest silence, 7 days
1 hourfrom Oct 9, 1:50 AM
Latest report
Oct 16, 12:50 AMlocal time
Time to reach Storm Station
13 min9 in 10 within 22 min

From Storm Station's own record of every report it heard from this station.

Its schedule is one report every hour, 24 in 24 hours. Two reports in the same hour count as one received.

Ranking Statistics

247 score98.4of 100

Maryland median
89.0the median score of 736 stations
Scoring higher
87stations in Maryland
Sharing its score
10ranks 88 to 97
Points deducted
1.60.8 forecast check, 0.6 arrival, 0.2 accuracy
Counted at the median
Accuracy, instrument checks, forecast checknot measured at this station; Maryland median 99.0, 100.0, 92.1
Next above
JONM2rank 88; ahead on median arrival 12 min 50 s against 12 min 58 s
Next below
BLDM2rank 93; behind on longest silence 60 min against 63 min
Sharing its rank
3other stations, equal on every measure

Equal scores are ordered by the share of scheduled reports received, then the reports due in the week (the longer record first), then the median arrival, then the longest silence.

  1. Reports receivedweight 35100.035.0 of 35 pointsMaryland median 82.1168 of 168 scheduled reports received in 7 days
  2. Arrivalweight 1094.19.4 of 10 pointsMaryland median 94.0half its reports arrived within 13 min
  3. Continuityweight 10100.010.0 of 10 pointsMaryland median 100.0longest silence 60 min, on a schedule of one report every 60 min
  4. Accuracyweight 20-19.8 of 20 points, at the medianMaryland median 99.0-
  5. Instrument checksweight 15-15.0 of 15 points, at the medianMaryland median 100.0-
  6. Forecast checkweight 10-9.2 of 10 points, at the medianMaryland median 92.1-

The score is the weighted mean of its six parts, from the last 7 days. How a station is ranked sets out each part.

How each part is scored
Reports received
Full marks for every scheduled report received, none for none, in proportion between
Arrival
Full marks for a median arrival within 10 min, none at 60 min
Continuity
Full marks for a longest silence of 3 reports or less (3 h), none for 72 (72 h)
Accuracy
Full marks within 1.5 °F of its reference, typically, none beyond 8.0 °F
Instrument checks
Full marks for no reading failed, none for 5 per cent or more
Forecast check
Full marks within 2 °F of the forecast on average, none at 8 °F

Near Potomac River at Little Falls

How to read a gauge

A gauge measures the height of the water where it stands, its stage, in feet above a fixed mark at that gauge. Two gauges' stages are not comparable: each is measured from its own mark, and a reservoir's is often its height above sea level.

The stage shown is the latest the gauge reported, with the time it reported it. Storm Station hears each gauge on its own schedule and ranks it among its state's stations by its 247 score, how reliably it reports and how its readings hold up: that is its 247 rank.