Two Atmospheric Sciences professors confirm the Northwest has had the coldest Spring since 1917.

Jun 10, 2008
By Scott Sistek

Is your barbecue collecting dust? It wouldn't be surprising...

We've used all sorts of statistics to come up with how chilly a spring it's been, but now two Atmospheric Sciences professors at the University of Washington, Cliff Mass and Mark Albright, have come up with a new way to measure the gloom: The "Barbecue Index."

And sure enough, it confirms what you've known all along -- it's been a bit cooler than average this spring.

Mass and Albright defined this index as the number of times since March 11 (the average date they consider the unofficial start to spring-like weather in the Northwest) it has been 60 degrees or warmer.

Why 60? They concluded that most people are comfortable outside once the temperature gets to 60 or better.

They went back to 1894 -- the farthest back they could get records for Seattle. Their conclusion? This is the worst Barbecue Index since 1917!
So far this year since March 11, Seattle has only reached 60 degrees or warmer 23 times. That is second-worst all-time, coming in runner-up to 1917's 18 score on the index. (At least you haven't had to spend much time cleaning the grills!)

The median number is 42 days. The best years were 1934 (74 out of days) and 1992 (62 days).

I've pasted below at the bottom of this entry the entire scoreboard of the Barbecue Index.

Good Illustration Of Why Our "BI" Is So Low

E-mail continues to pour in asking about why we've been stuck in such a cool pattern for so long. I've touched on this on previous blog entries (check the archives in the center column there to your right).

Generally speaking, our big ridge of high pressure that normally parks just offshore this time of year is parked father west, sending the jet stream up into Alaska, then down southeast right into the Pacific Northwest. That's tapping into some much cooler air in the northern latitudes and sending it our way. Sort of like opening a big door to our north and letting that Alaska air just blow right in.

As to why, it can be La Nina, or a host of other climate factors. Note that it's been cool in spring before -- this is not unprecedented. While we are looking at possibly setting a record for coldest June ever recorded, there have been other years with cool springs. It's just been a while. It just hasn't been this cold in the past 20 or 30 or so years, and memories fade :)

Anyway, here is the forecast chart of the next 8 days, showing the progression of yet another cool system from Alaska that is forecast to head our way for the middle of next week (although this one looks much weaker than the one we just went through):

Let's begin with Wednesday. I superimposed a red "L" on the approximate center of the low. The black lines are isobars / lines of constant pressure. The red and blue-dotted lines are atmospheric thickness -- a measure of temperature. (The '540' line changes from red to blue because over most of the nation, that line signifies the rain/snow line. However, out here, 540 is more of a 3,000 foot snow level line, or "Snow at Snoqualmie Pass" line. For lowland snow, we need to get down to about 516-522). The brown lines are the geographic boundaries to get your bearings. If it helps, Washington is at the bottom there near the date stamp.

And then watch over the next week as the low drops south of out Alaska toward the Northwest:

So yes, the forecast for middle of next week is a return to cool and showery weather. Guess that means another trip to Dicks for burgers :)

All time BBQ Index List:

Here is the "BBQ Index" All Time List for the 92 days between March 11 to June 10:
1. 1934 74
2. 1992 69
3. 1941 69
4. 1947 66
5. 1940 63
6. 1926 61
7. 2004 60
8. 1994 60
9. 1915 58
10. 1989 58
11. 1979 57
12. 1939 57
13. 1995 56
14. 1900 56
15. 1935 55
16. 2005 54
17. 1987 53
18. 1906 52
19. 1914 51
20. 1942 51
21. 1907 50
22. 1951 50
23. 1936 50
24. 1983 50
25. 1949 49
26. 1990 49
27. 1993 49
28. 1977 49
29. 1897 48
30. 1958 48
31. 1956 48
32. 2007 48
33. 1944 48
34. 1931 48
35. 2006 48
36. 1938 47
37. 1910 47
38. 1978 47
39. 1976 47
40. 1943 47
41. 1946 47
42. 1930 47
43. 1997 46
44. 1969 46
45. 1973 45
46. 1957 45
47. 1898 45
48. 1952 45
49. 1968 45
50. 1904 45
51. 1945 44
52. 1905 44
53. 1988 44
54. 1928 44
55. 1980 43
56. 2000 43
57. 1924 42
58. 1895 42
59. 1972 42
60. 1937 41
61. 1981 41
62. 1966 41
63. 1960 41
64. 1963 41
65. 1991 41
66. 1965 41
67. 1998 40
68. 1925 40
69. 1919 40
70. 1923 39
71. 1974 39
72. 1996 39
73. 1982 39
74. 1918 39
75. 1932 39
76. 1902 39
77. 1901 38
78. 1986 38
79. 2003 38
80. 1912 38
81. 1985 38
82. 1903 36
83. 1950 36
84. 1970 36
85. 2001 36
86. 1967 35
87. 1975 35
88. 2002 35
89. 1948 34
90. 1933 34
91. 1962 34
92. 1971 34
93. 1954 34
94. 1896 33
95. 1961 33
96. 1929 33
97. 1913 33
98. 1959 33
99. 1964 32
100. 1953 32
101. 1927 32
102. 1909 31
103. 1916 31
104. 1999 31
105. 1984 31
106. 1894 30
107. 1921 30
108. 1922 29
109. 1911 29
110. 1955 27
111. 1899 27
112. 1920 26
113. 1908 23
114. 2008 23
115. 1917 18