Monitored reservoir
Jackson Lake Near Moran, WY
United States Geological Survey reservoir gauge 13010500 in WY, with published storage from 1937.
Storage now, against this reservoir's own record
199.12 Mm³
Stored, September 1985
2nd
Percentile among 43 Seps on record
Storage in September 1985 was lower than almost every other Sep on record, ranked against 43 other Seps held for this reservoir.
Storage, 1937–1985
Monthly mean storage
516 monthly values, 1937 to 1985
Monthly means of the publisher's daily record. Volume, not percentage of capacity: without a capacity whose definition is stated, fullness cannot be computed.
View the data behind this chart
| Period | Jackson Lake Near Moran, WY (Mm³) |
|---|---|
| October 1937 | 292 |
| November 1937 | 316 |
| December 1937 | 349 |
| January 1938 | 383 |
| February 1938 | 418 |
| March 1938 | 451 |
| April 1938 | 493 |
| May 1938 | 636 |
| June 1938 | 1,002 |
| July 1938 | 1,010 |
| August 1938 | 750 |
| September 1938 | 569 |
| October 1938 | 503 |
| November 1938 | 541 |
| December 1938 | 573 |
| January 1939 | 608 |
| February 1939 | 642 |
| March 1939 | 672 |
| April 1939 | 714 |
| May 1939 | 924 |
| June 1939 | 1,046 |
| July 1939 | 953 |
| August 1939 | 640 |
| September 1939 | 417 |
| October 1939 | 402 |
| November 1939 | 421 |
| December 1939 | 438 |
| January 1940 | 467 |
| February 1940 | 497 |
| March 1940 | 532 |
| April 1940 | 570 |
| May 1940 | 736 |
| June 1940 | 1,017 |
| July 1940 | 800 |
| August 1940 | 407 |
| September 1940 | 207 |
| October 1940 | 222 |
| November 1940 | 251 |
| December 1940 | 275 |
| January 1941 | 308 |
| February 1941 | 336 |
| March 1941 | 360 |
| April 1941 | 388 |
| May 1941 | 523 |
| June 1941 | 774 |
| July 1941 | 699 |
| August 1941 | 439 |
| September 1941 | 295 |
| October 1941 | 306 |
| November 1941 | 348 |
| December 1941 | 391 |
| January 1942 | 431 |
| February 1942 | 464 |
| March 1942 | 489 |
| April 1942 | 526 |
| May 1942 | 642 |
| June 1942 | 948 |
| July 1942 | 991 |
| August 1942 | 678 |
| September 1942 | 436 |
| October 1942 | 403 |
| November 1942 | 428 |
| December 1942 | 470 |
| January 1943 | 518 |
| February 1943 | 555 |
| March 1943 | 574 |
| April 1943 | 498 |
| May 1943 | 642 |
| June 1943 | 991 |
| July 1943 | 1,052 |
| August 1943 | 1,002 |
| September 1943 | 845 |
| October 1943 | 805 |
| November 1943 | 805 |
| December 1943 | 802 |
| January 1944 | 821 |
| February 1944 | 844 |
| March 1944 | 874 |
| April 1944 | 905 |
| May 1944 | 993 |
| June 1944 | 1,051 |
| July 1944 | 983 |
| August 1944 | 669 |
| September 1944 | 408 |
| October 1944 | 378 |
| November 1944 | 404 |
| December 1944 | 428 |
| January 1945 | 458 |
| February 1945 | 490 |
| March 1945 | 520 |
| April 1945 | 547 |
| May 1945 | 659 |
| June 1945 | 940 |
| July 1945 | 1,044 |
| August 1945 | 876 |
| September 1945 | 719 |
| October 1945 | 715 |
| November 1945 | 749 |
| December 1945 | 781 |
| January 1946 | 817 |
| February 1946 | 804 |
| March 1946 | 757 |
| April 1946 | 700 |
| May 1946 | 916 |
| June 1946 | 1,049 |
| July 1946 | 966 |
| August 1946 | 671 |
| September 1946 | 513 |
| October 1946 | 517 |
| November 1946 | 556 |
| December 1946 | 597 |
| January 1947 | 634 |
| February 1947 | 667 |
| March 1947 | 697 |
| April 1947 | 732 |
| May 1947 | 933 |
| June 1947 | 1,051 |
| July 1947 | 1,016 |
| August 1947 | 823 |
| September 1947 | 605 |
| October 1947 | 591 |
| November 1947 | 627 |
| December 1947 | 661 |
| January 1948 | 698 |
| February 1948 | 728 |
| March 1948 | 761 |
| April 1948 | 788 |
| May 1948 | 844 |
| June 1948 | 1,039 |
| July 1948 | 924 |
| August 1948 | 562 |
| September 1948 | 313 |
| October 1948 | 306 |
| November 1948 | 339 |
| December 1948 | 380 |
| January 1949 | 416 |
| February 1949 | 451 |
| March 1949 | 458 |
| April 1949 | 467 |
| May 1949 | 682 |
| June 1949 | 1,014 |
| July 1949 | 941 |
| August 1949 | 625 |
| September 1949 | 383 |
| October 1949 | 357 |
| November 1949 | 392 |
| December 1949 | 423 |
| January 1950 | 458 |
| February 1950 | 503 |
| March 1950 | 541 |
| April 1950 | 554 |
| May 1950 | 565 |
| June 1950 | 888 |
| July 1950 | 1,041 |
| August 1950 | 872 |
| September 1950 | 699 |
| October 1950 | 726 |
| November 1950 | 773 |
| December 1950 | 810 |
| January 1951 | 812 |
| February 1951 | 772 |
| March 1951 | 657 |
| April 1951 | 522 |
| May 1951 | 657 |
| June 1951 | 972 |
| July 1951 | 1,041 |
| August 1951 | 972 |
| September 1951 | 842 |
| October 1951 | 775 |
| November 1951 | 799 |
| December 1951 | 834 |
| January 1952 | 850 |
| February 1952 | 811 |
| March 1952 | 691 |
| April 1952 | 541 |
| May 1952 | 682 |
| June 1952 | 1,022 |
| July 1952 | 942 |
| August 1952 | 657 |
| September 1952 | 417 |
| October 1952 | 360 |
| November 1952 | 383 |
| December 1952 | 410 |
| January 1953 | 453 |
| February 1953 | 498 |
| March 1953 | 531 |
| April 1953 | 565 |
| May 1953 | 650 |
| June 1953 | 931 |
| July 1953 | 991 |
| August 1953 | 681 |
| September 1953 | 395 |
| October 1953 | 299 |
| November 1953 | 327 |
| December 1953 | 359 |
| January 1954 | 396 |
| February 1954 | 440 |
| March 1954 | 477 |
| April 1954 | 518 |
| May 1954 | 701 |
| June 1954 | 959 |
| July 1954 | 1,017 |
| August 1954 | 761 |
| September 1954 | 468 |
| October 1954 | 406 |
| November 1954 | 437 |
| December 1954 | 468 |
| January 1955 | 500 |
| February 1955 | 530 |
| March 1955 | 565 |
| April 1955 | 603 |
| May 1955 | 698 |
| June 1955 | 953 |
| July 1955 | 928 |
| August 1955 | 578 |
| September 1955 | 304 |
| October 1955 | 255 |
| November 1955 | 294 |
| December 1955 | 343 |
| January 1956 | 406 |
| February 1956 | 449 |
| March 1956 | 463 |
| April 1956 | 319 |
| May 1956 | 383 |
| June 1956 | 901 |
| July 1956 | 1,010 |
| August 1956 | 787 |
| September 1956 | 523 |
| October 1956 | 475 |
| November 1956 | 467 |
| December 1956 | 146 |
| January 1957 | 82.3 |
| February 1957 | 125 |
| March 1957 | 168 |
| April 1957 | 207 |
| May 1957 | 357 |
| June 1957 | 821 |
| July 1957 | 1,008 |
| August 1957 | 889 |
| September 1957 | 781 |
| October 1957 | 757 |
| November 1957 | 746 |
| December 1957 | 744 |
| January 1958 | 753 |
| February 1958 | 731 |
| March 1958 | 652 |
| April 1958 | 572 |
| May 1958 | 658 |
| June 1958 | 974 |
| July 1958 | 977 |
| August 1958 | 851 |
| September 1958 | 691 |
| October 1958 | 594 |
| November 1958 | 579 |
| December 1958 | 582 |
| January 1959 | 579 |
| February 1959 | 586 |
| March 1959 | 595 |
| April 1959 | 601 |
| May 1959 | 684 |
| June 1959 | 926 |
| July 1959 | 1,013 |
| August 1959 | 873 |
| September 1959 | 718 |
| October 1959 | 673 |
| November 1959 | 653 |
| December 1959 | 623 |
| January 1960 | 602 |
| February 1960 | 593 |
| March 1960 | 589 |
| April 1960 | 608 |
| May 1960 | 724 |
| June 1960 | 995 |
| July 1960 | 971 |
| August 1960 | 827 |
| September 1960 | 611 |
| October 1960 | 442 |
| November 1960 | 436 |
| December 1960 | 432 |
| January 1961 | 427 |
| February 1961 | 365 |
| March 1961 | 207 |
| April 1961 | 171 |
| May 1961 | 266 |
| June 1961 | 586 |
| July 1961 | 392 |
| August 1961 | 68.3 |
| September 1961 | 5.08 |
| October 1961 | 27.4 |
| November 1961 | 63.8 |
| December 1961 | 99.8 |
| January 1962 | 130 |
| February 1962 | 157 |
| March 1962 | 191 |
| April 1962 | 233 |
| May 1962 | 479 |
| June 1962 | 866 |
| July 1962 | 1,010 |
| August 1962 | 845 |
| September 1962 | 698 |
| October 1962 | 645 |
| November 1962 | 644 |
| December 1962 | 654 |
| January 1963 | 667 |
| February 1963 | 704 |
| March 1963 | 729 |
| April 1963 | 759 |
| May 1963 | 872 |
| June 1963 | 1,051 |
| July 1963 | 1,016 |
| August 1963 | 876 |
| September 1963 | 765 |
| October 1963 | 736 |
| November 1963 | 724 |
| December 1963 | 740 |
| January 1964 | 765 |
| February 1964 | 781 |
| March 1964 | 781 |
| April 1964 | 781 |
| May 1964 | 799 |
| June 1964 | 947 |
| July 1964 | 1,034 |
| August 1964 | 887 |
| September 1964 | 740 |
| October 1964 | 723 |
| November 1964 | 718 |
| December 1964 | 728 |
| January 1965 | 757 |
| February 1965 | 722 |
| March 1965 | 641 |
| April 1965 | 535 |
| May 1965 | 516 |
| June 1965 | 796 |
| July 1965 | 1,039 |
| August 1965 | 955 |
| September 1965 | 808 |
| October 1965 | 786 |
| November 1965 | 817 |
| December 1965 | 848 |
| January 1966 | 866 |
| February 1966 | 862 |
| March 1966 | 859 |
| April 1966 | 853 |
| May 1966 | 879 |
| June 1966 | 1,035 |
| July 1966 | 996 |
| August 1966 | 856 |
| September 1966 | 704 |
| October 1966 | 587 |
| November 1966 | 589 |
| December 1966 | 598 |
| January 1967 | 607 |
| February 1967 | 620 |
| March 1967 | 624 |
| April 1967 | 624 |
| May 1967 | 575 |
| June 1967 | 877 |
| July 1967 | 1,030 |
| August 1967 | 879 |
| September 1967 | 724 |
| October 1967 | 698 |
| November 1967 | 716 |
| December 1967 | 726 |
| January 1968 | 734 |
| February 1968 | 742 |
| March 1968 | 748 |
| April 1968 | 752 |
| May 1968 | 798 |
| June 1968 | 971 |
| July 1968 | 1,032 |
| August 1968 | 911 |
| September 1968 | 764 |
| October 1968 | 733 |
| November 1968 | 757 |
| December 1968 | 763 |
| January 1969 | 778 |
| February 1969 | 800 |
| March 1969 | 804 |
| April 1969 | 773 |
| May 1969 | 792 |
| June 1969 | 1,028 |
| July 1969 | 1,030 |
| August 1969 | 911 |
| September 1969 | 761 |
| October 1969 | 708 |
| November 1969 | 734 |
| December 1969 | 743 |
| January 1970 | 756 |
| February 1970 | 773 |
| March 1970 | 777 |
| April 1970 | 776 |
| May 1970 | 745 |
| June 1970 | 930 |
| July 1970 | 1,031 |
| August 1970 | 921 |
| September 1970 | 780 |
| October 1970 | 688 |
| November 1970 | 688 |
| December 1970 | 706 |
| January 1971 | 727 |
| February 1971 | 740 |
| March 1971 | 747 |
| April 1971 | 713 |
| May 1971 | 525 |
| June 1971 | 743 |
| July 1971 | 1,041 |
| August 1971 | 922 |
| September 1971 | 782 |
| October 1971 | 742 |
| November 1971 | 742 |
| December 1971 | 756 |
| January 1972 | 772 |
| February 1972 | 777 |
| March 1972 | 755 |
| April 1972 | 686 |
| May 1972 | 551 |
| June 1972 | 861 |
| July 1972 | 1,032 |
| August 1972 | 937 |
| September 1972 | 778 |
| October 1972 | 725 |
| November 1972 | 737 |
| December 1972 | 751 |
| January 1973 | 769 |
| February 1973 | 781 |
| March 1973 | 787 |
| April 1973 | 792 |
| May 1973 | 867 |
| June 1973 | 1,024 |
| July 1973 | 1,008 |
| August 1973 | 892 |
| September 1973 | 785 |
| October 1973 | 746 |
| November 1973 | 761 |
| December 1973 | 775 |
| January 1974 | 788 |
| February 1974 | 800 |
| March 1974 | 813 |
| April 1974 | 737 |
| May 1974 | 553 |
| June 1974 | 814 |
| July 1974 | 1,027 |
| August 1974 | 907 |
| September 1974 | 745 |
| October 1974 | 725 |
| November 1974 | 731 |
| December 1974 | 736 |
| January 1975 | 748 |
| February 1975 | 764 |
| March 1975 | 775 |
| April 1975 | 786 |
| May 1975 | 663 |
| June 1975 | 670 |
| July 1975 | 995 |
| August 1975 | 912 |
| September 1975 | 740 |
| October 1975 | 718 |
| November 1975 | 737 |
| December 1975 | 757 |
| January 1976 | 771 |
| February 1976 | 776 |
| March 1976 | 784 |
| April 1976 | 731 |
| May 1976 | 587 |
| June 1976 | 845 |
| July 1976 | 1,009 |
| August 1976 | 883 |
| September 1976 | 705 |
| October 1976 | 699 |
| November 1976 | 703 |
| December 1976 | 706 |
| January 1977 | 718 |
| February 1977 | 730 |
| March 1977 | 748 |
| April 1977 | 774 |
| May 1977 | 836 |
| June 1977 | 807 |
| July 1977 | 572 |
| August 1977 | 390 |
| September 1977 | 300 |
| October 1977 | 290 |
| November 1977 | 305 |
| December 1977 | 332 |
| January 1978 | 367 |
| February 1978 | 395 |
| March 1978 | 408 |
| April 1978 | 404 |
| May 1978 | 463 |
| June 1978 | 620 |
| July 1978 | 758 |
| August 1978 | 735 |
| September 1978 | 662 |
| October 1978 | 663 |
| November 1978 | 669 |
| December 1978 | 689 |
| January 1979 | 707 |
| February 1979 | 698 |
| March 1979 | 673 |
| April 1979 | 630 |
| May 1979 | 618 |
| June 1979 | 748 |
| July 1979 | 742 |
| August 1979 | 677 |
| September 1979 | 619 |
| October 1984 | 339 |
| November 1984 | 344 |
| December 1984 | 344 |
| January 1985 | 345 |
| February 1985 | 338 |
| March 1985 | 328 |
| April 1985 | 172 |
| May 1985 | 214 |
| June 1985 | 350 |
| July 1985 | 344 |
| August 1985 | 289 |
| September 1985 | 199 |
Rate and persistence
14 of 24
Months in the last two years below the 20th percentile for their own month
Rates are computed only across an unbroken run of months, so a rate is never divided by a period in which some of the change was not observed. Percentile counts compare each month with the same calendar month in every other year held.
Location
Jackson Lake Near Moran, WY
Gauge location
Where this comes from
516 monthly observations 1937–1985 Mm³
Spatially aggregatedHigh confidenceSeptember 1985
Source: USGS — National Water Information System, 13010500. Licence: Open.
Method: Monthly mean of daily reservoir storage published by the USGS in acre-feet and converted to millions of cubic metres. Months with fewer than 20 days of record are not published rather than averaged from a partial month.
Reservoir storage is managed as well as observed: a drawdown may reflect an operating rule, flood-control rule curve or scheduled release rather than a shortage. Compare a month against the same month in other years, and do not read a fall as a supply signal without knowing the operating regime.
Retrieved 25 August 2026.
Monthly mean of daily reservoir storage published by the USGS in acre-feet and converted to millions of cubic metres. Months with fewer than 20 days of record are not published rather than averaged from a partial month.