SEATTLE CITY OFFICE, WASHINGTON

Monthly Total Heating Degree Days

(457488)

Base Temperature = 65 F

File last updated on Apr 4, 2013
*** Note *** Provisional Data *** After Year/Month 197210
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 84.00 54.50 69.75 a 180.50 390.00 602.00 807.50 2188.25
1949 974.50 703.50 543.50 395.00 184.50 138.00 76.00 41.00 114.00 433.50 405.00 720.50 4729.00
1950 1124.50 610.00 625.00 459.50 339.50 124.00 29.50 26.00 132.50 388.00 547.50 529.00 4935.00
1951 768.00 590.00 696.00 346.00 250.00 87.93 a 25.50 59.00 117.00 353.50 519.50 780.00 4592.43
1952 782.50 609.50 599.50 386.50 262.50 183.50 41.50 34.50 94.00 242.00 586.50 617.50 4440.00
1953 553.50 583.50 586.00 441.00 282.00 196.00 36.00 28.50 108.50 286.00 460.00 624.00 4185.00
1954 804.00 556.50 632.50 489.00 254.50 208.00 92.00 97.50 135.50 357.00 411.50 653.50 4691.50
1955 697.50 663.00 728.00 533.50 370.00 187.00 103.50 74.50 177.50 373.00 713.50 736.50 5357.50
1956 723.50 776.00 676.00 383.50 187.00 187.50 35.00 45.50 153.00 386.00 576.50 676.50 4806.00
1957 897.50 639.50 569.00 383.00 151.00 89.00 54.00 24.50 34.50 345.13 a 562.50 588.50 4338.13
1958 583.50 418.50 546.50 384.00 121.00 49.00 2.00 13.50 108.50 272.00 579.50 546.50 3624.50
1959 692.00 602.50 580.50 388.50 284.00 108.50 29.50 41.00 172.50 335.50 549.00 666.50 4450.00
1960 707.50 588.00 581.50 378.50 300.00 113.50 30.00 101.50 154.00 306.50 543.50 682.00 4486.50
1961 574.50 508.00 530.50 443.00 268.00 68.50 19.50 2.50 140.50 370.50 601.00 702.00 4228.50
1962 729.00 549.50 606.57 a 359.00 334.00 128.50 70.00 44.00 95.00 288.50 476.00 605.00 4285.07
1963 854.50 411.50 563.00 430.00 231.50 173.00 54.50 22.50 53.00 279.50 521.50 633.00 4227.50
1964 669.50 605.00 580.50 462.50 298.50 147.00 0.00 z 56.00 134.50 282.50 594.50 796.00 4626.50
1965 690.00 571.00 499.50 377.00 321.50 94.00 37.00 37.50 161.00 239.00 407.50 670.00 4105.00
1966 0.00 z 529.50 516.00 372.50 247.50 129.00 52.50 22.00 62.00 322.50 478.00 553.50 3285.00
1967 620.00 535.50 618.00 479.00 231.00 51.50 12.50 3.00 29.50 283.50 452.00 661.00 3976.50
1968 682.00 416.50 459.00 433.00 200.00 109.00 18.50 54.00 127.00 331.00 464.00 790.00 4084.00
1969 936.00 611.00 514.50 430.50 180.50 64.00 44.00 57.50 138.50 341.50 520.00 590.00 4428.00
1970 686.50 466.50 520.50 460.00 241.00 86.00 29.50 32.00 157.00 390.00 534.50 748.50 4352.00
1971 726.00 626.50 668.50 424.50 281.50 208.00 67.50 8.00 135.00 408.00 539.50 803.50 4896.50
1972 831.50 632.00 517.50 507.50 211.50 149.50 53.50 34.00 231.50 416.00 0.00 z 0.00 z 3584.50
Period of Record Statistics
MEAN 752.52 575.12 581.59 422.77 251.35 126.56 44.50 41.19 125.86 336.83 526.88 674.21 4438.98
S.D. 136.70 87.92 66.58 49.65 61.63 49.62 24.63 25.93 47.08 54.97 73.29 84.85 381.93
SKEW 0.92 -0.15 0.41 0.47 -0.15 0.19 0.63 0.68 -0.27 -0.11 0.22 0.07 0.30
MAX 1124.50 776.00 728.00 533.50 370.00 208.00 103.50 101.50 231.50 433.50 713.50 807.50 5357.50
MIN 553.50 411.50 459.00 346.00 121.00 49.00 2.00 2.50 29.50 239.00 405.00 529.00 3624.50
NO YRS 23 24 24 24 24 25 24 25 25 25 24 24 21