SEATTLE TACOMA INTL AP, WASHINGTON

Monthly Total Growing Degree Days

(457473)

Base Temperature = 50 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
1948 0.00 z 0.00 z 0.00 z 0.00 z 0.00 z 282.00 f 383.00 346.50 229.00 59.50 0.00 0.00 1018.00
1949 0.00 0.00 4.50 43.50 236.50 271.50 390.00 424.50 322.50 35.00 36.50 1.50 1766.00
1950 0.00 0.00 1.00 12.00 90.50 305.50 422.50 426.50 240.00 46.50 17.00 8.00 1569.50
1951 0.00 5.00 0.00 43.50 137.00 333.00 445.00 360.00 271.00 98.00 0.00 0.00 1692.50
1952 0.00 0.00 0.50 28.50 145.50 199.00 415.50 403.00 275.50 143.50 7.00 4.00 1622.00
1953 0.00 0.00 3.00 21.50 104.00 164.00 367.00 394.50 289.50 116.50 15.50 0.00 1475.50
1954 0.00 0.00 0.00 9.00 129.00 188.50 312.50 328.00 260.50 86.00 32.00 0.00 1345.50
1955 0.00 0.00 2.50 5.50 43.50 238.50 311.50 338.50 211.50 55.00 12.50 0.00 1219.00
1956 0.00 0.00 0.00 53.00 215.00 206.50 452.50 400.50 237.00 66.00 0.00 0.00 1630.50
1957 0.00 0.00 1.50 53.00 245.50 310.00 365.00 360.00 381.00 70.00 0.50 1.00 1787.50
1958 2.00 11.50 2.00 34.00 325.50 417.50 582.50 512.50 294.50 131.00 5.50 8.50 2327.00
1959 0.00 0.50 1.00 42.00 126.50 286.50 497.50 380.50 222.50 83.50 8.00 0.00 1648.50
1960 7.00 0.00 8.00 58.50 98.00 285.00 518.50 377.50 240.00 106.50 4.50 1.50 1705.00
1961 3.50 3.50 6.00 18.00 139.50 403.00 528.00 569.00 261.50 88.00 0.00 0.00 2020.00
1962 0.00 8.00 5.50 50.50 51.50 299.00 419.00 372.50 288.00 96.00 13.00 1.50 1604.50
1963 0.00 39.50 7.00 24.00 252.00 295.50 383.00 451.00 405.50 163.50 0.00 2.00 2023.00
1964 0.00 0.00 13.50 4.50 129.00 237.50 418.50 390.00 254.50 124.00 2.00 1.00 1574.50
1965 0.00 2.50 31.50 52.50 83.00 323.50 550.00 487.50 249.50 200.50 48.00 1.00 2029.50
1966 0.00 8.00 20.50 41.50 149.00 261.50 375.50 448.50 343.50 85.50 5.50 0.00 1739.00
1967 1.50 0.00 0.00 4.50 174.50 380.50 509.50 653.50 470.00 153.50 20.00 3.00 2370.50
1968 10.50 30.50 30.00 41.50 229.00 320.50 527.00 423.00 272.00 63.00 11.50 0.00 1958.50
1969 0.00 0.00 18.00 27.00 261.00 427.50 454.50 434.00 328.00 100.00 26.50 1.00 2077.50
1970 0.50 15.50 4.00 4.50 153.50 379.50 462.00 449.00 258.50 85.00 47.00 0.00 1859.00
1971 1.00 4.00 0.00 41.50 154.00 176.50 481.00 549.00 229.50 105.50 3.50 0.00 1745.50
1972 0.50 1.00 29.50 25.00 258.50 301.00 495.50 517.50 185.50 59.00 7.00 5.00 1885.00
1973 2.00 1.00 0.00 24.00 203.50 278.50 455.50 358.50 355.00 81.50 5.50 1.00 1766.00
1974 4.50 0.00 13.50 41.00 158.50 378.50 433.00 452.00 430.50 93.00 5.00 1.50 2011.00
1975 0.50 0.00 0.00 6.50 154.00 319.50 542.50 409.50 388.50 85.00 21.50 8.50 1936.00
1976 2.50 0.00 0.00 69.50 198.50 299.50 492.00 436.50 376.00 157.00 40.00 10.00 2081.50
1977 3.00 21.00 2.00 133.00 139.50 390.00 469.00 572.00 267.00 81.00 7.00 5.00 2089.50
1978 2.00 13.50 31.50 47.00 143.50 429.00 490.00 478.00 264.00 155.00 5.50 0.00 2059.00
1979 0.00 1.50 35.00 77.00 222.50 374.50 539.00 432.00 378.00 137.50 12.00 1.50 2210.50
1980 0.00 11.00 3.50 77.00 134.00 224.00 426.50 369.50 288.00 135.00 43.50 23.00 1735.00
1981 18.00 6.00 28.00 60.50 152.50 225.00 411.50 560.00 330.50 46.50 26.00 0.00 1864.50
1982 0.00 2.50 0.00 30.00 150.00 393.50 395.50 467.00 316.50 110.00 1.50 1.00 1867.50
1983 3.50 13.50 19.50 71.00 242.50 296.50 410.50 484.00 249.00 66.50 29.00 0.00 1885.50
1984 8.50 0.00 17.00 28.00 96.00 263.50 464.50 462.50 296.00 84.00 2.50 0.00 1722.50
1985 0.00 0.00 0.50 41.00 165.50 301.00 576.00 469.00 243.00 76.00 8.00 0.00 1880.00
1986 0.50 19.50 29.00 23.50 189.00 379.00 363.50 570.50 273.00 139.50 4.00 0.00 1991.00
1987 3.00 17.00 35.50 92.50 217.00 376.50 439.50 500.00 375.50 183.00 42.50 0.00 2282.00
1988 0.00 5.50 5.00 68.00 165.00 287.50 474.00 476.00 317.50 177.50 10.50 3.00 1989.50
1989 0.00 0.00 3.50 128.50 188.00 395.50 448.50 472.50 421.00 122.50 18.50 6.50 2205.00
1990 0.00 2.00 13.00 78.00 147.00 295.00 557.50 534.50 401.00 57.50 26.50 0.00 2112.00
1991 0.50 19.00 3.00 37.50 136.50 265.00 519.50 513.50 385.00 159.00 22.00 2.00 2062.50
1992 11.50 24.50 34.50 131.50 305.00 448.00 516.50 520.00 299.00 144.50 4.00 0.00 2439.00
1993 0.00 11.00 14.00 43.00 298.00 315.50 345.00 479.50 355.00 168.00 0.50 6.50 2036.00
1994 2.00 3.00 47.00 88.00 252.50 316.50 554.50 537.00 430.00 95.00 0.00 5.00 2330.50
1995 12.50 13.50 43.50 84.50 313.00 380.50 527.00 400.50 419.50 101.50 40.00 4.50 2340.50
1996 1.00 3.50 22.50 75.50 110.00 312.50 553.00 509.00 276.00 100.50 8.00 1.00 1972.50
1997 1.50 0.00 6.00 28.00 253.50 282.50 447.50 549.50 364.50 71.50 22.50 0.00 2027.00
1998 4.00 7.50 27.50 66.50 152.50 296.00 545.00 519.50 394.00 103.50 7.00 2.00 2125.00
1999 0.00 0.00 8.50 51.00 94.50 244.00 385.00 457.50 323.50 82.00 26.50 0.00 1672.50
2000 0.00 0.00 1.50 65.00 128.00 317.00 442.50 417.00 305.00 98.00 0.00 0.00 1774.00
2001 1.50 0.00 6.00 37.50 172.50 228.00 385.00 458.00 292.50 67.00 16.50 0.00 1664.50
2002 5.00 0.00 0.00 28.50 124.50 333.00 463.50 471.00 317.50 86.50 20.50 3.00 1853.00
2003 2.50 0.00 20.00 30.00 164.50 384.00 552.50 508.00 377.50 154.50 0.50 0.00 2194.00
2004 0.50 2.00 29.00 106.50 216.00 400.00 562.00 529.50 265.00 124.50 5.00 4.50 2244.50
2005 22.00 3.50 36.50 85.00 254.50 297.50 482.00 519.00 285.00 130.00 0.00 22.00 2137.00
2006 7.00 1.50 7.50 59.00 212.00 392.50 542.50 493.00 368.50 105.00 22.00 0.00 2210.50
2007 0.50 1.00 22.00 66.00 206.00 309.50 550.50 483.50 297.50 56.50 9.00 3.50 2005.50
2008 0.00 1.00 3.50 22.00 193.00 251.00 462.50 492.50 329.50 78.50 42.50 2.50 1878.50
2009 1.00 0.50 1.00 50.50 198.50 413.00 603.00 483.00 372.00 97.50 9.50 1.00 2230.50
2010 10.50 1.50 15.00 43.50 112.00 249.50 450.50 476.50 326.50 117.00 28.50 3.00 1834.00
2011 4.00 0.00 1.00 2.00 79.50 281.50 439.00 490.50 419.50 88.50 4.00 0.50 1810.00
2012 0.00 3.50 1.00 64.50 172.50 248.00 442.00 554.50 381.50 138.50 34.50 1.50 2042.00
2013 0.00 0.00 39.00 4.50 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 39.00
Period of Record Statistics
MEAN 2.49 5.23 12.55 48.45 174.16 310.66 465.01 464.05 316.53 104.25 14.69 2.50 1925.73
S.D. 4.41 8.22 13.49 30.58 63.68 67.95 69.34 67.50 64.80 37.37 14.03 4.37 254.49
SKEW 2.54 2.08 0.87 0.82 0.35 0.02 -0.12 0.06 0.27 0.48 0.87 3.18 -0.26
MAX 22.00 39.50 47.00 133.00 325.50 448.00 603.00 653.50 470.00 200.50 48.00 23.00 2439.00
MIN 0.00 0.00 0.00 2.00 43.50 164.00 311.50 328.00 185.50 35.00 0.00 0.00 1219.00
NO YRS 65 65 65 64 64 64 65 65 65 65 65 65 64