National Weather Service California Nevada River Forecast Center Department of Commerce National Oceanic and Atmospheric Administration National Weather Service



TUOLUMNE RIVER - HETCH HETCHY RESERVOIR (HETC1)
Latitude: 37.95º NLongitude: 119.79º WElevation: 3870 Feet
Location: Tuolumne County in CaliforniaBulletin Group: San JoaquinRiver Group: San Joaquin
Issuance Time: Jul 10, 2025 at 8:32 AM PDT
Please Note:Flow data on this product are unregulated / full natural flow.
Historical Flows
RankYearAnnual Flow3-Year Mean
197131536000000703.2
197263072000000523.9
197394694400000801.8 676.3
1974126230400000916.4 747.4
1975157766400000781.7 833.3
1976189302400000293.0 663.7
1977220924800000205.8 426.8
19782524608000001158.8 552.5
1979283996800000723.3 696.0
19803155328000001149.1 1010.4
1981347155200000454.2 775.6
19823786912000001339.5 980.9
19834102272000001645.2 1146.3
19844417632000001025.0 1336.6
1985473385600000538.1 1069.4
19865049216000001178.3 913.8
1987536457600000316.4 677.6
1988567993600000391.4 628.7
1989599616000000622.4 443.4
1990631152000000385.3 466.4
1991662688000000469.6 492.4
1992694224000000355.4 403.4
1993725846400000981.3 602.1
1994757382400000372.1 569.6
19957889184000001458.5 937.3
1996820454400000933.3 921.3
19978520768000001158.4 1183.4
19988836128000001117.0 1069.6
1999915148800000797.5 1024.3
2000946684800000693.5 869.3
2001978307200000455.9 649.0
20021009843200000627.5 592.3
20031041379200000712.8 598.7
20041072915200000596.5 645.6
200511045376000001034.3 781.2
200611360736000001192.5 941.1
20071167609600000368.9 865.3
20081199145600000524.6 695.4
20091230768000000757.6 550.4
20101262304000000822.3 701.5
201112938400000001378.6 986.1
20121325376000000384.4 861.7
20131356998400000469.8 744.3
20141388534400000332.2 395.5
20151420070400000264.8 355.6
20161451606400000785.3 460.8
201714832288000001746.7 932.3
20181514764800000647.9 1060.0
201915463008000001070.1 1154.9
20201577836800000348.6 688.8
20211609459200000278.9 565.9
20221640995200000500.3 376.0
202316725312000001543.3 774.2
20241704067200000617.0 886.9
20251735689600000 559.3 906.5

Location Photographs

ESRI™ Locator Map
Official 7 Day National Weather Service Forecast   (CAZ323)
Today: Sunny. Highs 71 to 83. Southeast winds up to 10 mph shifting to the southwest in the afternoon.

Tonight: Clear. Lows 48 to 62. Northwest winds up to 10 mph shifting to the east after midnight.

Saturday: Sunny. Highs 71 to 83. East winds up to 5 mph shifting to the southwest in the afternoon.

Saturday Night: Clear. Lows 48 to 62. West winds up to 10 mph shifting to the northeast after midnight.

Sunday: Sunny. Highs 72 to 84. Northeast winds up to 5 mph shifting to the southwest in the afternoon.

Sunday Night through Tuesday Night: Clear. Lows 44 to 62. Highs 70 to 85.

Wednesday: Sunny. Highs 67 to 79.

Wednesday Night: Mostly clear. Lows 44 to 56.

Thursday: Sunny. Highs 66 to 78.