Is Summer Over?

September 2, 2010


I hate to be negative, but…  

 Looking at the maps for the next 7-10 days, models all show a cool trough sitting over the Western USA in one form or another.  You can see the negative anomaly in the 500mb 6-10 forecast map from CPC.  Keep in mind that 10 days takes us just about halfway into September.  The 2nd half of September is rarely “summery”, sure some warm days some years, but rarely a long period of warm & sunny weather.  Put that together with the forecast pattern which is very similar to one we’ve seen a good chunk of the summer, and it’s possible that we won’t have a string of 80+ degree days on the way again (3 or more).   It boils down to this: after tomorrow we go back to at least a week of cool Fall weather again…highs in the 60s and 70s.

Quite a different story tonight as the east wind keeps blowing on the hills and near/in the Gorge.  Temps in the mid-upper 70s and wind still gusting in the 25-35 mph range out there.  It’ll gradually die down overnight and should just be a light breeze in the Gorge by morning.  Then a switch to onshore flow late tomorrow afternoon.  A mild night and a late marine push spells another day in the mid 80s Friday.  Enjoy, since it’ll be a big change Saturday.

We’ve painted a somewhat gloomy picture for the weekend the last few days.  One saving grace may be that the cool marine layer will be disturbed by the upper-level trough quite a bit Saturday and Sunday, plus no inversion due to the cool air above.  So partly cloudy is possible both of those days…touching up forecasts a bit as we speak.

If you’re looking for a warm end to “Summer”, forget about it this weekend.

Chief Meteorologist Mark Nelsen