Cold (but drier) Spring Continues

April 19, 2011

Here’s a nice chart showing how chilly the first 19 days of April have been.  Today was below average again, by 6 degrees on both the high and low temps at PDX.

The chart is from the National Weather Service in Portland.  You can see the green area is the 30 year average for high and low temperatures.  The blues and reds are the record low and high temperatures…the warmest and coldest we’ve seen on any one day.  Note that we’ve only seen two days at/above average for the high temperature (out of 19!).  Notice also that most record highs are now in the 80 degree range…wouldn’t that be nice? 

It’s fair to say this is becoming a cold spring historically.  Not an “epic” cold spring…unless the current pattern continues through May, but one of the coldest we’ve seen (so far) in this area.  We’ve only seen 3 60 degree days so far, which is the lowest number ever at PDX. 

That’s the fewest number of 60 degree days by April 19th in 70+ years! 

If you look at Downtown records, we’re at the 2nd lowest in 137 years…just as unusual.  We’ve seen a rare combination of:  a cold period in the 2nd half of February, a slightly cooler than average March, followed by a very chilly April.  In most other years, even if late Winter and Spring is chilly, we get some sort of brief warm spell.  Sometimes it’s in late February, other years in March, or April of course.  In fact during the very cold La Nina Spring of 2008, we hit 80 degrees in parts of the Metro Area the 2nd week of April…then the cool weather resumed.  But this year we haven’t even seen a hint of warming, not a single briefly warm ridge.  Very strange indeed.  And we are alone here in the West, take a look at the USA temperature anomaly for the last 30 days (Celsius):

It has been unusually warm across the southcentral and southeast USA, but about average from the Great Lakes eastward up north.

A nice change the last few days has been the dry weather and sunshine.  Saturday was a screwed up forecast, but the bright sun Sunday, Monday, and today was a welcome change.  Keep in mind the sun angle right now is similar to late August, which explains why it FEELS warmer than 55 degrees at mid-afternoon in the sunshine.  But once the sun goes down it feels like Halloween weather.  I was at my daughter’s first softball game yesterday evening and we could see our breath by the time the game ended at 8pm…about 45 degrees!

My eyes are on that 70 degree record for May 5th…that’s the latest we’ve had our “first 70” of the season.  The year was 1967.  Anybody remember that one?  A searing hot summer followed (a 107 degree day too), so keep in mind that a cold spring doesn’t mean anything with respect to our upcoming summer.

Chief Meteorologist Mark Nelsen