Today we are getting a break from the cold (more on this later). But I thought it would be interesting to unearth the old "Barbecue Index"---the number of days we have hit 60F or more this spring (to be exact from March 21st to May 11) at Sea-Tac Airport. This is the kind of rigorous research one expects from the UW!
The answer: the index shows this is the WORST YEAR since record-keeping began at this location with only five days reaching 60F. Here is the plot (courtesy of Neal Johnson of the UW):
Even more irritating to many is the trend of the past 7 years---downward.
A big question is whether we are going into a cold (negative) phase of the Pacific Decadal Oscillation--a natural variation over the eastern Pacific basin (see PDO index below). We were in a cold phase during the fifties to the mid 70s, followed by a warm phase until the early 2000s. But what are we in now? A new cold phase?
Here is an amazing image....it shows the difference (anomaly) between the temperature in the lower atmosphere (850 mb--roughly 5000 ft) and normal (climatology) considering the period from March 15th to May 11th. Very large cold "bulls eye" over the Northwest, while a warm center is found over Texas. Says it all. It also illustrates why you can't talk about global warming my looking at ONE location---we might be cold, while others are warmer than normal.
Many of you are asking about this summer. We are now in a rapidly weakening La Nina and our forecast models indicate a cool period later this weekend into early next week. No major warm ups in sight for next week. This summer we will be in a neutral pattern (neither La Nina nor El Nino) and in any case we have little if any skill for summer predictions. So I can't tell you and neither can anyone else.
But one positive....today we will get into the mid-60s and Saturday will be decent (low 60s with increasing clouds) and generally dry (few showers at most). But Saturday night we head back into serious rain and Sunday will be a loss....cool and wet again. In any case, this is better than droughts and wildfires (Texas), tornadoes (Alabama), or flooding along the Mississippi. Or the extreme snow of the eastern U.S. last winter.
Lets face it, weather is rarely normal, particularly if you look across the entire continent. We need to learn how to better predict it (my field's job) and adapt to it (everyone's job). You don't live in mobile home parks in tornado country if you can help it, nor by a large river that periodically floods.