The Perfect Weather Pattern? July So Far

July 10, 2017

10pm Monday

The weather is extremely slow this week once again as we continue under an unusually stable summertime weather pattern.  Let’s be honest, it’s pretty boring in the weather center.  That’s fine though, summer is time for hiking, camping, bicycling, and all sorts of water sports.  Time for some vacation days!

Today is our 24th consecutive dry day in Portland; not unusual, but as mentioned in previous posts it started a bit earlier than normal.  In fact the rainfall anomaly (percent above/below average) for the past 2 months shows spring ended and summer started drier than normal; quite a turnaround from winter and early spring.


Temperatures have been running about 2 degrees above normal here in Portland, but anywhere east of the Cascades it has been a scorching hot first 1/3rd of July:

4 of the past 5 years we’ve seen these above normal temps in early July.

There is no sign that we’ll see a return to either cool and showery weather (unusual in mid to late July) or extreme heat in the next 10 days.  Take a look at the 500 millibar (18,000′) height anomaly for this coming Saturday.  It shows the western ridge strengthening once again, but far enough to our east to avoid a heat wave west of the Cascades:


Looking ahead to NEXT Wednesday, the 19th?  The ridge weakens a bit, but upper-level heights are right around normal.  Normal above = average tempratures down here where we all live.

Then out to Day 10…

The ridge might try to strengthen a bit again…maybe some warming.  But nothing extreme heat-wise.  Keep in mind this is from the ECMWF ensembles, which is a collection of many different runs as opposed to looking at just one run of the model.  Note the GEFS ensembles (from the somewhat inferior American equivalent GFS model)

show little or no rain in the next two weeks, which seems reasonable in the pattern shown by the Euro model above.  I think most of us would say we deserve this unusually stable summer weather pattern after the winter of nearly constant rain, freezing rain & snow.  So get out and enjoy what nature is providing you this Summer of 2017!

Chief Meteorologist Mark Nelsen