A New Record…Still No 65 Degree Days

April 18, 2017

11pm Tuesday…

We just set a new record today; a chilly one!

WE’VE NEVER GONE THIS FAR INTO THE SPRING SEASON WITHOUT HITTING 65 DEGREES.  The previous records were in April 1945 & 1950.  In those years (as you see below), we finally made it over 65 on the 18th of the month. We didn’t do that today so now we’re in uncharted territory for PDX and a new record has been set for latest “FIRST 65 DEGREE DAY”.  Of course those records go back about 80 years.

Capture

Check out the warmest temperature each of the last 11 Aprils in Portland:

MarkAprilMaxTemp

It’s pretty typical to see 75 or even low 80s at some point during the month.  But I think that’s unlikely this year as we stay in a regime with weather systems frequently passing through the region.  Still no sign of anything more than one or two days with brief upper-level ridging.  Take a look at the 12z ECMWF 850mb ensemble forecast:

tseries_850t_000-360_Portland

There is very good agreement through the 27th with these ensembles.  You see the spike of warm air later Friday through SaturdayAM.  But then it’s back down to near/below normal temps up around that 5,000′ elevation.  There is quite a bit of “noise” right in the last couple of days this month.  That means the different ensemble members diverge a bit, but that’s normal for 10+ days out.  This evening’s GEFS (GFS ensembles) is quite similar:

tseries_850t_000-384_Portland

except there are quite a few warmer ensembles around the end of the month.  Even with what we consider a “cool pattern”, this month has still be pretty reasonable.  Most stations in Oregon are running at or less than 2 degrees below normal.  Here’s the USA analysis, which seems a bit cool compared to actual observations for our area:

conus_mtd_t2max_anom_2017

Compare it to the first 17 days of April last year!  Wow…what a crazy warm month that was and a temperature pattern across the USA reversed from this year.

conus_mtd_t2max_anom_2016

By the way…even with the “cool-ish” 10 days ahead, our daylight does keep increasing.

MarkSunset8pm

The sun set at 8:01pm in Portland today and will set beyond 8pm for the next 4 months.  The next “pre-8pm” sunset will be the weekend before Labor Day (August 26th).  Enjoy the long days!

Chief Meteorologist Mark Nelsen