This July Is Sure Different!

July 12, 2016

9pm Tuesday…

It finally happened!  Tuesday I received my first two “I HATE THIS SUMMER” emails.  Actually they were more like “WHAT’S GOING ON?” emails lamenting the lack of warm weather this summer so far…  Here’s one, click for a better view:

Capture

Let’s look at the facts first.  Temperature anomaly (departure from the average) for the past 10 days:

anomaly_10days

Coolest part of the USA compared to average is right over in the NE part of Oregon and northern Rockies.  July so far…

anomaly_july

Same general idea with a good chunk of the USA cooler than normal.  Now back 30 days; that started just a few days after our 100 degree Sunday!

anomaly_30days

This coolish pattern has been going on awhile…as mentioned in previous posts, it appears some sort of climate “switch” was switched on/off after the first week of June.

But we haven’t been all that cool; in fact Salem and Eugene have seen perfectly normal temps for July!  The coast has actually been warmer than normal.  So it’s not like we’ve seen a “chilly” July.   I think we have just become comfortable with warmer than normal temps of the past few summers, or at least we get used to it.  Specifically many of us have expected we can go out and enjoy those water sports just about any day in July and not be chilled.

This one graphic  tells the story:

Mark_80DegreeJulyDays

Last year 25 days at/above 80 degrees, this year it appears we’ll see 5-6 at most in the first 20 days of the month.  That’s MUCH different than the past 3-4 years!

The reason we are seeing the much cooler temps?  A flattened western USA upper-level ridge along with cool upper-level troughs wanting to hang out near the West Coast.

WHAT’S AHEAD?

Models beyond the 7-10 day period have been quite poor at forecasting this pattern.  They have been continuously pushing the ridge back to it’s typical summertime position in the 10-15 day timeframe.  So confidence on a switch to normal or above normal weather is quite low until it shows up within the 7-10 day period.  That said, we do have some warmer and sunny weather the next 3 days, then models have backed off a bit on the upper-level low this weekend.    The ECMWF ensembles keep us near/below normal for the next 10 days.

ecmwf

The GFS ensembles are a bit warmer, but I’ll trust the ECMWF for now and assume this pattern will continue through at least the 20th-22nd of the month.

By the way, there was quite a bit of frost in south central and southeast Oregon Monday morning.  Burns dropped to 30 degrees, although not as cold as the record July cold temp…25 degrees back in July 1986.

MarkTemperature_BurnsRecordLow

Winter is never TOO far away in Burns is it?

Chief Meteorologist Mark Nelsen