Some Early Summer Weather This Week

June 3, 2013

5pm Monday…

When I look at the maps/models today, the “look” screams “SUMMER!”.  Not that there is any sort of heat wave or even hot weather on the way, but a good week of above average temperatures and lots of sunshine.  Perfect for outdoor activities, catching up on yard work, sitting on the deck, etc…

The pattern (which was well advertised/forecast the past week) is more of a July pattern with the weak summer jet stream well to the north and flat upper-level ridging near or over the West Coast.  Here’s the Friday morning forecast of 500mb height anomaly from the GFS ensemble forecasts:

ecmwf_fri

Note the big yellow-green area over us showing above average (warmer than normal) heights over us.  It’s quite a positive anomaly with heights up in the 580-588 range.  Typically in summer we can get 90+ temps out of such high heights, but not when you get a flat ridge like this along the West Coast.  In this setup we don’t get the high pressure developing to our east and offshore flow.  So it’s 850mb temps around +15 with light onshore flow.  That should be enough to get highs into the low-mid 80s.

With such high heights all week-long we don’t get a huge intrusion of marine air at any point, so anything “worse” than morning/midday low clouds is unlikely through the weekend.

Next week is still in the 7-10 day range, but models are actually in pretty good agreement that at least weak upper-level troughing develops again along the West Coast.  Here are the anomaly maps from the 18z GFS, 12z GEM, & 12z ECMWF:

gfs_wed

can_wed

ecmwf_wed

They all show the throughing over us next Wednesday.  This trend is also on the 850mb temp chart on the 12z ECMWF:

tseries_850t_000-360_Portland

A warm and dry week; time to plant all the rest of the warm weather veggies!  Then cooler and maybe wet weather next week.

Chief Meteorologist Mark Nelsen


ECMWF Weekly Maps

June 3, 2013

I’ve been busy and/or lazy the past few days with no posts.  Here is last night’s monthly run of the ECMWF.  4 weeks of 500mb height anomalies.  Looks like some sort of troughing NEXT week; well advertised in the operational runs of most models right now.  Then some sort of ridging again the last half of the month?…maybe.

500za_week1_bg_NA

500za_week2_bg_NA

500za_week3_bg_NA

500za_week4_bg_NA