Flow report
Maryland streamflow
Live discharge, gauge height, water temperature, and percent-of-normal readings from every USGS streamgauge in Maryland. Built for paddlers, anglers, water managers, and flood researchers.
USGS gauges
92
State percent normal
104%
Paddle runs
0
Updated
Jul 15
Open the Maryland flow layer on the map
Every USGS streamgauge filtered to Maryland.
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July
15
2026
Flow briefing
Streamflow levels across Maryland are currently 104% of normal, with the Susquehanna River At Conowingo reporting the highest discharge in the state at 5,900 cfs and a gauge stage of 9.49 ft.
Meanwhile, the Potomac River At Hancock is seeing a spike today — up 5% since yesterday and currently running near peak.
Tap any gauge below for the full hydrograph, paired weather forecast, and historical context. Use the rivers panel to jump into Maryland's named rivers.
River levels near Maryland towns
Active weather warnings for Maryland
# Maryland Storm Center Report
Maryland residents should take precautions as multiple Heat Advisories remain in effect until 8:00 PM EDT today, with dangerously high heat index values reaching 104-109 degrees across the state. Affected areas include north central and western Maryland, Kent, Queen Annes, and Talbot Counties, as well as southeast Maryland, with particular concern for major population centers including Baltimore, Annapolis, and the Washington DC suburban region. Additionally, Code Orange Air Quality Alerts are active statewide through midnight Wednesday, affecting the Eastern Shore (Cambridge, Salisbury, Ocean City), Baltimore City Metro, Northeast Maryland, and the suburban DC region. Sensitive groups—including children, elderly, and those with asthma, heart disease, or lung conditions—should avoid strenuous outdoor activity. Heat-related illnesses are a significant risk; stay hydrated, seek air-conditioned spaces, and monitor vulnerable family members and neighbors.
Maryland residents should take precautions as multiple Heat Advisories remain in effect until 8:00 PM EDT today, with dangerously high heat index values reaching 104-109 degrees across the state. Affected areas include north central and western Maryland, Kent, Queen Annes, and Talbot Counties, as well as southeast Maryland, with particular concern for major population centers including Baltimore, Annapolis, and the Washington DC suburban region. Additionally, Code Orange Air Quality Alerts are active statewide through midnight Wednesday, affecting the Eastern Shore (Cambridge, Salisbury, Ocean City), Baltimore City Metro, Northeast Maryland, and the suburban DC region. Sensitive groups—including children, elderly, and those with asthma, heart disease, or lung conditions—should avoid strenuous outdoor activity. Heat-related illnesses are a significant risk; stay hydrated, seek air-conditioned spaces, and monitor vulnerable family members and neighbors.
Maryland at a glance
State-wide streamflow overview
The Maryland flow picture in four data points -- where the state sits versus historical norms, what's flowing hardest, and what's spiking fastest.
Percent of normal
104%
100% is the historical norm. Below 70% indicates drought; above 130% can flag elevated flood risk.
Highest discharge
Susquehanna River At Conowingo
5,900 cfs
Gauge stage 9.49 ft
Biggest 24h spike
Potomac River At Hancock
+5%
Now 2,240 cfs
Network coverage
Gauges + rivers tracked
92 + 0
USGS gauges feeding 0 named rivers in Maryland.
Full streamgauge inventory
Maryland USGS streamgauges
Every USGS gauge Snoflo tracks in Maryland. Sortable, quickly filterable. Numeric columns heat-mapped from light to deep. Tap any gauge for its full hydrograph and forecast.
| Streamgage | Streamflow | Gage height | Water temp | Air temp | Elevation | Watershed |
|---|---|---|---|---|---|---|
|
Susquehanna River At Conowingo, Md
10 hours ago · USGS 01578310 |
5,900 cfs | 9.49 ft | · | 70°F | 21 ft | Lower Susquehanna |
|
Potomac River At Point Of Rocks, Md
11 hours ago · USGS 01638500 |
4,030 cfs | 2.02 ft | 85°F | 73°F | 192 ft | Middle Potomac-Catoctin |
|
Potomac River Near Wash, Md
11 hours ago · USGS 01646500 |
3,800 cfs | 3.17 ft | 45°F | 74°F | 43 ft | Middle Potomac-Catoctin |
|
Potomac River At Hancock, Md
10 hours ago · USGS 01613000 |
1,740 cfs | 3.95 ft | · | 73°F | 396 ft | Conococheague-Opequon |
|
Potomac River At Paw Paw, Md
10 hours ago · USGS 01610000 |
1,360 cfs | 4.84 ft | · | 72°F | 501 ft | Cacapon-Town |
|
North Branch Potomac River Near Cumberland, Md
10 hours ago · USGS 01603000 |
484 cfs | 2.66 ft | · | 71°F | 589 ft | North Branch Potomac |
|
Monocacy River At Jug Bridge Near Frederick, Md
10 hours ago · USGS 01643000 |
221 cfs | 1.83 ft | · | 70°F | 231 ft | Monocacy |
|
Youghiogheny River At Friendsville, Md
11 hours ago · USGS 03076500 |
203 cfs | 2.61 ft | 72°F | 67°F | 1,555 ft | Youghiogheny |
|
Gunpowder Falls At Glencoe, Md
10 hours ago · USGS 01582500 |
186 cfs | 1.57 ft | · | 70°F | 247 ft | Gunpowder-Patapsco |
|
Gunpowder Falls Near Parkton, Md
10 hours ago · USGS 01581920 |
166 cfs | 2.22 ft | 62°F | 71°F | 352 ft | Gunpowder-Patapsco |
|
Monocacy River At Monocacy Blvd At Frederick, Md
10 hours ago · USGS 01642190 |
161 cfs | 1.86 ft | · | 70°F | 259 ft | Monocacy |
|
Conococheague Creek At Fairview, Md
11 hours ago · USGS 01614500 |
151 cfs | 1.62 ft | · | 71°F | 438 ft | Conococheague-Opequon |
|
Youghiogheny River Near Oakland, Md
10 hours ago · USGS 03075500 |
122 cfs | 2.42 ft | · | 63°F | 2,370 ft | Youghiogheny |
|
Antietam Creek Near Sharpsburg, Md
10 hours ago · USGS 01619500 |
115 cfs | 2.37 ft | · | 70°F | 367 ft | Conococheague-Opequon |
|
Patuxent River Below Brighton Dam Near Brighton, Md
11 hours ago · USGS 01591610 |
110 cfs | 2.01 ft | 70°F | 70°F | 310 ft | Patuxent |
|
Patuxent River Near Bowie, Md
10 hours ago · USGS 01594440 |
107 cfs | 4.12 ft | · | 72°F | 20 ft | Patuxent |
|
North Branch Potomac River At Kitzmiller, Md
10 hours ago · USGS 01595500 |
103 cfs | 2.22 ft | · | 69°F | 1,575 ft | North Branch Potomac |
|
Wills Creek Near Cumberland, Md
10 hours ago · USGS 01601500 |
76 cfs | 2.18 ft | · | 72°F | 703 ft | North Branch Potomac |
|
Savage Riv Bl Savage Riv Dam Near Bloomington, Md
10 hours ago · USGS 01597500 |
63 cfs | · | 56°F | 70°F | 1,382 ft | North Branch Potomac |
|
Seneca Creek At Dawsonville, Md
11 hours ago · USGS 01645000 |
62 cfs | 2.07 ft | · | 70°F | 216 ft | Middle Potomac-Catoctin |
|
Deer Creek Near Darlington, Md
10 hours ago · USGS 01580520 |
59 cfs | 1.07 ft | · | 72°F | 49 ft | Lower Susquehanna |
|
North Branch Potomac River At Steyer, Md
10 hours ago · USGS 01595000 |
50 cfs | 2.29 ft | · | 66°F | 2,276 ft | North Branch Potomac |
|
Bear Creek At Friendsville, Md
10 hours ago · USGS 03076600 |
48 cfs | 1.77 ft | · | 67°F | 1,640 ft | Youghiogheny |
|
Deer Creek At Rocks, Md
10 hours ago · USGS 01580000 |
39 cfs | 2.00 ft | · | 73°F | 262 ft | Lower Susquehanna |
|
Patapsco River At Hollofield, Md
10 hours ago · USGS 01589000 |
38 cfs | 1.41 ft | · | 71°F | 190 ft | Gunpowder-Patapsco |
|
Town Creek Near Oldtown, Md
10 hours ago · USGS 01609000 |
33 cfs | 2.17 ft | · | 70°F | 567 ft | Cacapon-Town |
|
Casselman River At Grantsville, Md
10 hours ago · USGS 03078000 |
31 cfs | 1.02 ft | · | 66°F | 2,135 ft | Youghiogheny |
|
Monocacy River At Bridgeport, Md
10 hours ago · USGS 01639000 |
29 cfs | 2.51 ft | · | 71°F | 332 ft | Monocacy |
|
Antietam Creek Near Waynesboro, Md
10 hours ago · USGS 01619000 |
29 cfs | 2.19 ft | · | 71°F | 547 ft | Conococheague-Opequon |
|
Big Elk Creek At Elk Mills, Md
11 hours ago · USGS 01495000 |
26 cfs | 3.13 ft | · | 71°F | 70 ft | Chester-Sassafras |
|
Little Patuxent River At Savage, Md
10 hours ago · USGS 01594000 |
22 cfs | 2.85 ft | · | 73°F | 126 ft | Patuxent |
|
Gwynns Falls At Washington Blvd At Baltimore, Md
10 hours ago · USGS 01589352 |
21 cfs | 2.33 ft | · | 73°F | 18 ft | Gunpowder-Patapsco |
|
Little Falls At Blue Mount, Md
10 hours ago · USGS 01582000 |
19 cfs | · | · | 70°F | 306 ft | Gunpowder-Patapsco |
|
North East Branch Anacostia River At Riverdale, Md
10 hours ago · USGS 01649500 |
19 cfs | · | 78°F | 73°F | 14 ft | Middle Potomac-Anacostia-Occoquan |
|
Georges Creek At Franklin, Md
11 hours ago · USGS 01599000 |
19 cfs | 2.06 ft | · | 71°F | 975 ft | North Branch Potomac |
|
Bennett Creek At Park Mills, Md
10 hours ago · USGS 01643500 |
18 cfs | 1.54 ft | · | 72°F | 304 ft | Monocacy |
|
Patuxent Riv Near Laurel, Md
10 hours ago · USGS 01592500 |
17 cfs | 4.28 ft | · | 74°F | 160 ft | Patuxent |
|
Western Run At Western Run, Md
10 hours ago · USGS 01583500 |
16 cfs | · | · | 72°F | 265 ft | Gunpowder-Patapsco |
|
Big Pipe Creek At Bruceville, Md
10 hours ago · USGS 01639500 |
16 cfs | · | · | 71°F | 370 ft | Monocacy |
|
Savage River Near Barton, Md
10 hours ago · USGS 01596500 |
16 cfs | 1.08 ft | 69°F | 67°F | 1,659 ft | North Branch Potomac |
|
North Branch Patapsco River At Cedarhurst, Md
10 hours ago · USGS 01586000 |
14 cfs | 1.27 ft | · | 71°F | 423 ft | Gunpowder-Patapsco |
|
St Marys River At Great Mills, Md
10 hours ago · USGS 01661500 |
13 cfs | 1.60 ft | · | 71°F | 13 ft | Lower Potomac |
|
Little Gunpowder Falls At Laurel Brook, Md
10 hours ago · USGS 01584500 |
13 cfs | 1.01 ft | · | 72°F | 260 ft | Gunpowder-Patapsco |
|
Patuxent River Near Unity, Md
11 hours ago · USGS 01591000 |
12 cfs | 1.97 ft | · | 70°F | 383 ft | Patuxent |
|
Sideling Hill Creek Near Bellegrove, Md
10 hours ago · USGS 01610155 |
12 cfs | · | · | 74°F | 482 ft | Cacapon-Town |
|
Tuckahoe Creek Near Ruthsburg, Md
11 hours ago · USGS 01491500 |
12 cfs | · | · | 73°F | 14 ft | Choptank |
|
Catoctin Creek Near Middletown, Md
11 hours ago · USGS 01637500 |
11 cfs | 1.59 ft | · | 71°F | 436 ft | Middle Potomac-Catoctin |
|
Western Branch At Upper Marlboro, Md
10 hours ago · USGS 01594526 |
10 cfs | 1.52 ft | · | 74°F | 9 ft | Patuxent |
|
Hawlings River Near Sandy Spring, Md
11 hours ago · USGS 01591700 |
10 cfs | · | · | 70°F | 307 ft | Patuxent |
|
Cattail Creek Near Glenwood, Md
11 hours ago · USGS 01591400 |
9 cfs | · | · | 70°F | 382 ft | Patuxent |
|
Jones Falls At Sorrento, Md
10 hours ago · USGS 01589440 |
8 cfs | 7.77 ft | · | 73°F | 236 ft | Gunpowder-Patapsco |
|
Winters Run Near Benson, Md
10 hours ago · USGS 01581700 |
8 cfs | 1.18 ft | · | 72°F | 190 ft | Gunpowder-Patapsco |
|
Beaverdam Run At Cockeysville, Md
10 hours ago · USGS 01583600 |
8 cfs | 2.05 ft | · | 72°F | 245 ft | Gunpowder-Patapsco |
|
Gwynns Falls At Villa Nova, Md
10 hours ago · USGS 01589300 |
8 cfs | · | · | 72°F | 367 ft | Gunpowder-Patapsco |
|
Zekiah Swamp Run Near Newtown, Md
10 hours ago · USGS 01660920 |
7 cfs | · | · | 70°F | 37 ft | Lower Potomac |
|
Unicorn Branch Near Millington, Md
10 hours ago · USGS 01493000 |
7 cfs | 1.27 ft | · | 74°F | 8 ft | Chester-Sassafras |
|
Morgan Run Near Louisville, Md
10 hours ago · USGS 01586610 |
7 cfs | 1.29 ft | · | 72°F | 430 ft | Gunpowder-Patapsco |
|
Gunpowder Falls At Hoffmanville, Md
10 hours ago · USGS 01581810 |
7 cfs | · | · | 72°F | 550 ft | Gunpowder-Patapsco |
|
Choptank River Near Greensboro, Md
10 hours ago · USGS 01491000 |
6 cfs | 1.79 ft | 79°F | 73°F | 5 ft | Choptank |
|
Marsh Run At Grimes, Md
10 hours ago · USGS 01617800 |
6 cfs | 1.06 ft | · | 71°F | 405 ft | Conococheague-Opequon |
|
Beaver Run Near Finksburg, Md
10 hours ago · USGS 01586210 |
6 cfs | · | · | 71°F | 431 ft | Gunpowder-Patapsco |
|
Little Patuxent River At Guilford, Md
10 hours ago · USGS 01593500 |
6 cfs | 1.63 ft | · | 73°F | 267 ft | Patuxent |
|
Georges Run Near Beckleysville, Md
10 hours ago · USGS 01581870 |
5 cfs | · | · | 73°F | 521 ft | Gunpowder-Patapsco |
|
Piney Run At Dover, Md
10 hours ago · USGS 01583100 |
4 cfs | 1.39 ft | · | 73°F | 380 ft | Gunpowder-Patapsco |
|
Beetree Run At Bentley Springs, Md
10 hours ago · USGS 01581960 |
4 cfs | · | · | 73°F | 491 ft | Gunpowder-Patapsco |
|
Pocomoke River Near Willards, Md
11 hours ago · USGS 01485000 |
4 cfs | 4.26 ft | · | 72°F | 22 ft | Pocomoke |
|
St Clement Creek Near Clements, Md
10 hours ago · USGS 01661050 |
3 cfs | · | · | 70°F | 11 ft | Lower Potomac |
|
Sawmill Creek At Glen Burnie, Md
11 hours ago · USGS 01589500 |
3 cfs | 1.87 ft | · | 74°F | 34 ft | Gunpowder-Patapsco |
|
Grave Run Near Beckleysville, Md
10 hours ago · USGS 01581830 |
3 cfs | · | · | 72°F | 560 ft | Gunpowder-Patapsco |
|
Long Green Creek At Glen Arm, Md
10 hours ago · USGS 01584050 |
2 cfs | · | · | 72°F | 290 ft | Gunpowder-Patapsco |
|
Chicamacomico River Near Salem, Md
10 hours ago · USGS 01490000 |
2 cfs | · | · | 72°F | 2 ft | Blackwater-Wicomico |
|
Nassawango Creek Near Snow Hill, Md
10 hours ago · USGS 01485500 |
2 cfs | 1.32 ft | · | 73°F | 21 ft | Pocomoke |
|
Bynum Run At Bel Air, Md
10 hours ago · USGS 01581500 |
2 cfs | · | · | 72°F | 260 ft | Gunpowder-Patapsco |
|
Sallie Harris Creek Near Carmichael, Md
11 hours ago · USGS 01492500 |
2 cfs | · | · | 75°F | 14 ft | Chester-Sassafras |
|
Nw Branch Anacostia River Near Colesville, Md
11 hours ago · USGS 01650500 |
2 cfs | 1.36 ft | · | 72°F | 271 ft | Middle Potomac-Anacostia-Occoquan |
|
Morgan Creek Near Kennedyville, Md
11 hours ago · USGS 01493500 |
2 cfs | 1.19 ft | · | 74°F | 4 ft | Chester-Sassafras |
|
Dead Run At Franklintown, Md
10 hours ago · USGS 01589330 |
2 cfs | · | · | 72°F | 313 ft | Gunpowder-Patapsco |
|
Gwynns Falls Near Delight, Md
11 hours ago · USGS 01589197 |
2 cfs | · | · | 73°F | 536 ft | Gunpowder-Patapsco |
|
Mattawoman Creek Near Pomonkey, Md
11 hours ago · USGS 01658000 |
1 cfs | 2.00 ft | 73°F | 71°F | 46 ft | Lower Potomac |
|
Whitemarsh Run At White Marsh, Md
10 hours ago · USGS 01585100 |
1 cfs | 3.25 ft | · | 74°F | 42 ft | Gunpowder-Patapsco |
|
Plumtree Run Near Bel Air, Md
10 hours ago · USGS 01581752 |
1 cfs | · | 73°F | 72°F | 187 ft | Gunpowder-Patapsco |
|
Piscataway Creek At Piscataway, Md
10 hours ago · USGS 01653600 |
1 cfs | 1.97 ft | · | 70°F | 16 ft | Middle Potomac-Anacostia-Occoquan |
|
Birch Branch At Showell, Md
11 hours ago · USGS 0148471320 |
1 cfs | 3.14 ft | · | 73°F | 6 ft | Chincoteague |
|
Cranberry Branch Near Westminster, Md
10 hours ago · USGS 01585500 |
1 cfs | 1.29 ft | · | 72°F | 672 ft | Gunpowder-Patapsco |
|
East Branch Herbert Run At Arbutus, Md
10 hours ago · USGS 01589100 |
1 cfs | · | · | 72°F | 49 ft | Gunpowder-Patapsco |
|
Honeygo Run Near White Marsh, Md
11 hours ago · USGS 01585104 |
0 cfs | · | · | 73°F | 25 ft | Gunpowder-Patapsco |
|
West Branch Herring Run At Idlewylde, Md
10 hours ago · USGS 01585200 |
0 cfs | · | · | 74°F | 286 ft | Gunpowder-Patapsco |
|
Whitemarsh Run Near Fullerton, Md
11 hours ago · USGS 01585090 |
0 cfs | 1.06 ft | · | 74°F | 138 ft | Gunpowder-Patapsco |
|
Manokin Branch Near Princess Anne, Md
10 hours ago · USGS 01486000 |
0 cfs | 1.46 ft | · | 73°F | 14 ft | Pocomoke |
|
Minebank Run Near Glen Arm, Md
10 hours ago · USGS 0158397967 |
0 cfs | 4.09 ft | · | 74°F | 225 ft | Gunpowder-Patapsco |
|
Baisman Run At Broadmoor, Md
10 hours ago · USGS 01583580 |
0 cfs | 1.08 ft | · | 75°F | 333 ft | Gunpowder-Patapsco |
|
South Fork Jabez Branch At Millersville, Md
11 hours ago · USGS 01589795 |
0 cfs | 3.20 ft | · | 73°F | 60 ft | Severn |
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Flow report FAQ
About Maryland streamflow
Where does the Maryland streamflow data come from?
The U.S. Geological Survey National Water Information System. USGS streamgauges report continuously (every 15 minutes) and the data is the canonical real-time record for U.S. rivers. Snoflo pulls the latest readings and joins them to a 7-day NOAA weather forecast for each station.
What is cfs?
Cubic feet per second — the standard unit for streamflow. One cfs is about 7.5 gallons per second. Small creeks run at single-digit cfs; the Mississippi at hundreds of thousands.
What does Gauge Height mean?
The water level at the gauge in feet above the reference datum. Used together with discharge to track river state. Flood stage and runnable levels are typically expressed in gauge height (e.g., "flood at 16 ft").
How fresh is the Maryland data?
USGS streamgauges report every 15 minutes; Snoflo re-pulls throughout the day. The AI briefing regenerates daily.
Can I get a flow alert for a Maryland gauge?
Yes. Save any USGS gauge as a favorite in the Snoflo iOS app, set a discharge or stage threshold (e.g. "alert me when discharge crosses 2,000 cfs"), and you'll get a push the moment it crosses.
Is this a substitute for an NWS flood warning?
No. Snoflo is informational. For flood life-safety decisions always follow guidance from your local NWS forecast office and state emergency management. Snoflo data is one input among several.
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