Quite a change the last few days. Most of us were in the 50s and lower 60s with showers/thunderstorms Friday. Yesterday was a clouds to sunshine day; good news for for Grand Floral Parade day. Temps rose 5-10 degrees. Then another 10 degrees warming today brought temps well above average once again:
The big picture says we’re going to be quite warm for the next 10 days or so. From the ECMWF model you see upper-level heights (ridging in this case) above average through the next 15 days. The three images represent Days 1-5, 6-11, and 11-15. That takes us through the first three weeks of June.
Looks to me like it’s going to be our 7th June with average to above average temps. Those three cold Junes 2010-2012 seem like a long time ago now.
What about rain? Little or none in the next 10 days. Each line on the top half of this chart shows one ensemble member. Quite a few show less than .10″ in the next 15 days! This may be the beginning of the dry season. If so, it’s going to be a long one again…
And well below average rain the next 15-16 days forecast by both ECMWF and GFS ensemble systems. Wet weather continues across the saturated central/eastern USA.
In the short term, tomorrow should be similar to today, but up a few degrees. Then the big change is a switch to easterly wind Tuesday through Wednesday midday. You can see it circled on the WRF-GFS cross-section over Portland. The 11/12 along bottom axis = June 11th at 5am, and 12/12 = June 12th at 5am.
At the same time 850mb temps rise up to +21 or +22 over Salem. According to my chart, based on past similar setups, we should see high temps both days between 95-100 degrees. Cooling onshore flow doesn’t arrive until Wednesday evening after peak heating. Whew!
Luckily a quick cooling overhead along with low-level onshore flow should drop us into the 80s Thursday and then down around 80 Friday. This won’t be a many days-long heatwave. Still, daily record highs will probably fall both Tuesday/Wednesday
Stay cool! Chief Meteorologist Mark Nelsen