Weather Blog

New 'Barbecue Index' confirms -- it's been a chilly spring

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