YELLOWSTONE PK MAMMOTH, WYOMING

Monthly Total Heating Degree Days

(489905)

Base Temperature = 65 F

File last updated on Apr 4, 2013
*** Note *** Provisional Data *** After Year/Month 201303
a = 1 day missing, b = 2 days missing, c = 3 days, ..etc..,
z = 26 or more days missing, A = Accumulations present
Long-term means based on columns; thus, the monthly row may not
sum (or average) to the long-term annual value.
Months with 5 missing days or less use mean for missing day(s)
Individual Months not used for annual or monthly statistics if more than 5 days are missing.
Individual Years not used for annual statistics if any month in that year has more than 5 days missing.
YEAR(S JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC ANN
1894 1482.50 1479.50 1172.50 0.00 z 0.00 z 0.00 z 35.50 4.00 323.50 328.00 o 873.50 1393.50 6764.50
1895 1437.50 1282.50 392.50 v 0.00 z 238.00 r 416.50 173.50 115.50 449.50 669.00 1168.50 1425.50 7138.00
1896 1238.50 1152.00 1238.50 921.50 723.50 262.50 114.50 154.00 479.42 d 728.50 1403.50 1159.50 9575.92
1897 0.00 z 1246.00 1411.00 814.00 340.00 339.50 166.00 91.50 299.00 747.00 1045.50 1424.50 7924.00
1898 1558.50 1115.50 1370.00 734.00 619.50 225.50 h 113.50 92.00 392.50 898.00 1196.00 1482.00 9571.50
1899 1381.50 1517.50 1300.00 878.00 700.50 363.00 128.00 249.00 314.00 853.00 882.50 1430.50 9997.50
1900 1331.00 643.00 o 923.44 e 691.00 448.50 142.50 145.00 155.50 451.50 702.50 1082.00 1253.50 7326.44
1901 1351.00 1315.00 1170.50 881.50 396.00 442.50 34.00 83.50 543.33 c 603.00 918.00 e 1351.82 c 9090.16
1902 1474.50 1073.00 1237.50 851.50 517.50 335.00 222.50 181.50 420.50 645.00 1083.50 1308.50 9350.50
1903 1314.50 1460.50 1130.00 848.50 626.50 242.50 179.00 137.50 471.50 611.00 998.00 1252.00 9271.50
1904 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1905 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1906 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1907 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1908 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1909 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1910 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1911 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1912 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1913 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1914 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1915 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1916 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1917 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1918 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1919 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1920 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1921 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1922 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1923 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1924 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1925 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1926 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1927 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1928 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1929 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1930 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1931 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1932 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1933 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1934 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1935 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1936 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1937 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1938 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1939 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1940 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00
1941 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 301.50 97.00 164.00 557.50 769.50 1039.00 1253.43 a 4181.93
1942 1432.50 1315.00 1180.50 667.50 667.00 411.00 72.50 105.00 363.00 704.50 1104.00 1253.95 a 9276.45
1943 0.00 z 1142.00 1301.00 626.00 636.00 393.50 98.50 115.50 300.00 602.50 936.50 1275.50 7427.00
1944 1380.50 1226.00 1253.00 774.50 493.00 388.50 167.00 168.50 374.50 568.50 1068.50 1363.00 9225.50
1945 1269.00 1147.50 1103.50 951.00 593.50 478.50 103.50 99.00 452.50 569.88 a 1075.50 1377.00 9220.38
1946 1367.00 1162.50 1000.50 672.00 635.50 265.00 51.50 148.00 462.50 972.00 1138.00 1273.50 9148.00
1947 1543.00 1221.50 1152.00 889.50 545.50 484.50 83.50 215.00 432.50 652.00 1287.93 a 1400.50 9907.43
1948 1500.00 1387.00 1353.00 890.00 589.50 332.50 192.00 192.00 406.55 a 710.50 1296.00 1619.50 10468.55
1949 1899.50 1355.93 a 1192.50 740.17 a 485.00 320.17 a 83.50 76.98 a 361.50 884.00 804.00 1354.50 9557.75
1950 1611.00 1058.00 1226.50 874.00 714.50 324.50 165.50 172.00 454.50 612.50 1041.50 1145.50 9400.00
1951 1498.50 1099.78 a 1277.00 830.40 e 517.00 502.50 125.50 198.00 451.00 830.00 1126.50 1487.50 9943.68
1952 1417.00 1249.00 1286.50 715.50 565.50 303.10 a 135.50 141.00 242.00 f 546.00 1174.00 1270.00 8803.10
1953 1097.50 1161.50 1049.50 928.00 697.00 316.03 a 0.00 z 82.15 a 259.50 574.50 854.00 1342.30 a 8361.98
1954 1347.00 1011.00 1242.00 761.00 516.50 444.00 e 66.13 a 166.00 337.50 745.00 878.00 1346.50 8860.63
1955 1487.00 1348.50 1390.00 897.00 569.50 355.50 122.50 46.00 401.50 662.50 1264.00 1331.50 9875.50
1956 1304.00 1407.02 a 1158.50 833.00 474.50 196.00 116.50 190.00 323.00 712.50 1206.00 1307.00 9228.02
1957 1709.50 1104.00 1121.00 855.50 491.00 316.00 54.00 127.00 412.50 737.50 1199.00 1207.00 9334.00
1958 1294.00 953.00 1182.00 861.50 348.75 a 272.50 169.50 109.50 362.50 628.00 1085.00 1196.50 8462.75
1959 1359.50 1272.00 1157.50 839.00 698.02 a 245.00 116.50 173.50 462.50 774.50 1167.50 1286.50 9552.02
1960 1411.50 1401.50 1120.50 840.00 580.50 258.00 55.50 191.00 336.00 689.75 a 1073.50 1299.00 9256.75
1961 1291.84 b 987.78 a 563.50 l 876.92 d 540.50 90.50 h 48.50 81.00 597.50 797.00 1105.34 a 1438.40 a 7764.79
1962 1669.35 a 1188.50 1201.50 728.00 535.02 b 287.00 150.00 164.50 375.00 567.00 935.00 1222.78 d 9023.64
1963 1734.40 b 970.00 1079.50 850.50 523.90 a 344.46 b 72.85 a 99.72 a 216.72 a 508.50 956.79 b 1330.93 a 8688.27
1964 1405.85 a 1317.43 a 1282.50 809.00 494.00 349.29 b 36.17 a 222.74 d 436.15 d 627.50 1081.00 1075.00 g 8061.62
1965 1289.82 c 1181.38 b 1115.50 h 812.88 d 634.47 a 335.00 141.50 172.00 454.50 g 560.07 a 912.00 1240.00 b 7279.12
1966 1401.41 b 1256.08 c 1111.50 919.29 b 375.00 g 339.44 c 32.60 b 186.00 a 0.00 z 0.00 z 0.00 z 0.00 z 5246.33
1967 0.00 z 756.50 j 1082.13 d 745.00 f 601.00 361.00 43.00 62.00 237.50 673.45 b 1016.90 a 1537.08 a 5614.06
1968 1400.50 1102.50 972.37 a 935.56 c 622.00 303.50 78.53 a 254.00 386.50 642.00 1089.50 1372.00 9158.96
1969 1354.50 1128.81 a 1232.50 668.79 a 427.50 370.50 96.50 59.93 a 245.00 884.50 1006.50 1237.62 e 8712.66
1970 1350.50 997.92 c 1327.00 1018.00 528.50 232.50 58.50 23.50 511.55 a 840.00 1045.00 1368.43 c 9301.40
1971 1371.00 1196.50 1250.33 d 850.56 c 0.00 z 262.50 113.50 25.00 466.07 b 790.50 a 1090.34 a 1475.50 8891.80
1972 1487.50 1156.00 923.50 778.50 522.00 193.50 150.50 105.50 441.21 a 726.20 d 1063.50 1585.00 9132.91
1973 1444.00 1087.50 1061.50 921.50 545.00 246.50 68.50 79.50 409.50 644.50 0.00 z 1269.21 e 7777.21
1974 1486.00 1175.48 a 1157.33 a 802.50 631.50 189.50 33.50 182.50 398.00 601.00 1062.50 1129.50 f 7719.81
1975 1512.05 b 1327.93 a 1264.00 1101.50 688.50 367.00 23.50 208.00 347.00 683.50 1150.50 1208.00 9881.48
1976 1307.00 1160.50 1226.00 752.00 468.50 346.11 c 53.00 200.00 277.50 f 748.50 933.62 a 1305.00 8500.23
1977 1491.50 1041.25 d 1184.89 d 687.12 d 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 414.50 k 0.00 z 1048.00 f 4404.75
1978 0.00 z 0.00 z 0.00 z 766.11 c 425.00 j 256.00 79.50 150.00 356.50 374.50 j 71.50 z 231.00 z 1608.11
1979 1378.50 g 1189.50 1127.00 818.50 531.13 a 288.10 a 34.50 117.50 234.44 c 631.07 c 1251.21 a 1237.50 7460.46
1980 1560.85 a 1163.62 a 915.00 g 745.56 c 342.00 g 287.14 b 69.23 a 205.12 a 340.38 d 585.00 f 1021.07 b 1148.00 6540.98
1981 1129.00 1184.75 d 971.52 c 772.50 d 429.50 f 379.20 e 0.00 z 0.00 z 0.00 z 435.00 o 611.00 i 935.50 i 4436.97
1982 1507.50 1281.50 1103.00 990.00 275.00 p 314.00 117.50 42.00 226.00 o 0.00 z 1186.50 1358.00 7900.00
1983 1181.00 1022.50 1003.50 880.50 651.50 339.50 161.00 0.00 z 338.50 f 0.00 z 1041.50 1638.50 7919.50
1984 1407.50 1160.00 1051.50 866.90 a 590.50 337.00 48.50 40.00 0.00 z 0.00 z 1058.50 0.00 z 6560.40
1985 1483.00 1390.50 1184.00 723.00 337.50 i 257.59 a 68.50 0.00 z 519.00 801.50 1369.50 1419.50 9216.09
1986 1181.00 1076.00 816.00 768.50 562.50 125.50 161.50 91.50 534.00 711.00 1110.00 1336.50 8474.00
1987 1431.00 1073.50 1057.00 599.50 427.50 233.50 183.50 182.50 317.50 625.50 968.50 1393.00 8492.50
1988 1513.00 1217.50 1167.50 744.00 482.50 120.00 44.50 93.00 373.00 504.00 1080.50 1404.00 8743.50
1989 1404.50 1485.00 1151.00 768.50 565.50 288.50 28.00 159.50 374.00 737.00 1019.00 1398.00 9378.50
1990 1294.00 1237.00 1047.50 704.00 625.00 294.00 78.00 77.00 191.00 773.50 1000.50 1735.50 9057.00
1991 1436.00 936.50 1086.00 860.00 602.00 252.50 47.00 32.50 344.50 772.00 1209.00 1312.50 8890.50
1992 1301.00 981.50 837.00 656.00 395.50 247.50 219.00 157.00 399.00 620.50 1178.00 1486.00 8478.00
1993 1457.00 1285.50 997.50 828.00 460.50 358.00 328.50 229.50 425.00 735.50 1252.50 1302.50 9660.00
1994 1165.50 1286.50 982.00 740.50 385.00 249.50 122.00 31.00 250.00 736.00 1289.00 1239.50 8476.50
1995 1336.00 1030.50 1133.00 832.00 639.00 354.50 118.00 100.00 363.50 855.50 984.83 a 1275.00 9021.83
1996 1468.50 1273.50 1205.50 802.00 687.00 200.50 34.00 83.00 435.00 742.00 1049.50 1351.00 9331.50
1997 1460.00 1193.00 1081.00 973.50 514.00 239.00 122.50 129.50 310.50 766.50 1091.50 1383.00 9264.00
1998 1248.50 1081.50 1101.00 793.00 515.00 496.00 12.50 43.00 228.00 713.00 991.50 1425.00 8648.00
1999 1247.00 1114.50 1051.00 919.00 636.50 344.00 101.00 78.00 466.50 632.50 802.00 1275.00 8667.00
2000 1295.00 1062.50 1052.00 721.00 578.00 274.50 49.00 50.50 414.00 723.50 1350.00 1411.00 8981.00
2001 1400.68 a 1289.50 1031.00 822.00 456.00 270.00 35.50 45.47 a 229.50 724.37 a 913.50 1429.50 8647.02
2002 1444.50 1270.00 1346.50 879.50 628.00 262.50 33.00 185.50 346.50 918.50 1137.50 1265.50 9717.50
2003 1203.00 1281.50 1096.00 786.50 557.50 290.00 18.50 58.00 392.00 625.00 0.00 z 1297.50 7605.50
2004 1395.50 1247.50 910.00 710.50 603.50 334.00 98.50 175.50 398.00 625.00 989.50 1192.50 8680.00
2005 1238.50 1067.00 1023.00 751.50 531.00 316.00 35.50 119.00 327.50 585.00 1010.00 1385.00 8389.00
2006 1176.50 0.00 z 1069.50 703.50 453.00 171.50 11.00 76.00 342.50 778.50 1012.50 1301.50 7096.00
2007 1508.50 1095.50 858.50 727.50 434.50 140.00 i 1.50 72.00 318.00 742.50 983.00 1398.00 8139.50
2008 1501.00 1141.50 1299.00 1025.50 352.00 j 314.50 49.50 74.00 405.50 705.00 890.50 1500.00 8906.00
2009 1393.00 1124.00 1193.00 846.00 527.00 353.00 117.00 113.50 209.00 997.50 1013.00 1559.30 a 9445.30
2010 1312.50 1138.00 976.50 824.00 692.00 322.00 121.62 e 117.00 299.50 551.50 1159.50 1248.00 8762.12
2011 1362.00 1371.50 1036.00 906.00 665.50 353.50 52.00 51.50 240.00 606.00 1093.50 1356.00 9093.50
2012 1231.00 1190.50 909.50 634.00 599.00 269.00 16.00 53.00 246.50 754.50 924.00 1278.50 8105.50
2013 1412.00 1131.50 1092.23 a 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 3635.73
Period of Record Statistics
MEAN 1397.15 1192.50 1131.21 813.68 556.40 308.73 93.74 121.83 374.71 703.99 1070.38 1349.36 9143.26
S.D. 138.98 132.27 131.90 98.42 92.11 79.16 59.82 60.54 89.95 106.33 129.43 115.48 491.08
SKEW 0.61 0.34 -0.15 0.24 -0.25 0.13 0.98 0.16 0.02 0.49 0.31 0.84 0.26
MAX 1899.50 1517.50 1411.00 1101.50 723.50 502.50 328.50 254.00 597.50 997.50 1403.50 1735.50 10468.55
MIN 1097.50 936.50 816.00 599.50 340.00 120.00 1.50 4.00 191.00 504.00 802.00 1145.50 8105.50
NO YRS 77 78 77 78 70 77 79 78 73 73 76 75 51