Weather Blog

September a journey back to June weather?

September a journey back to June weather?
View of a cloudy Seattle on July 15, 2012. (Image courtesy: Puget Sound Clean Air Agency visibility camera.)

August is set to go down as much warmer than normal, breaking a streak of three months that were quite the opposite.

But the long range forecasts just issued by the NOAA's Climate Prediction Center Thursday indicate our warm month streak will likely end at just one.

Their 30-day forecast for September indicated a significant chance of a cooler-than-normal conditions across much of the far West Coast with an even higher chance of cooler than normal temperatures along and west of the I-5 corridor in Washington and Oregon.


Left: Blue=Cooler than normal / Brown=Warmer                                 Right: Green=Wetter than normal/Brown=Drier

This essentially mimics what they had for June and July, which verified fairly well and shows that the big heat ridge of high pressure that had moved west into our neck of the woods for August, will drift back into the central and Eastern U.S. as it had earlier in the summer, baking them and leaving us a bit cooler. They are also indicating that ocean temperatures just offshore remain cooler than normal, also a limiting factor in temperatures in the absence of a big heat ridge around.

On the other hand, the long range forecast also says we have a very high chance of being drier than normal across the Pacific Northwest.

But once we get past September, the long range forecasts for fall and winter take on a very El Nino flavor, with very high chances of a warmer and drier December through April.