How Unusual Has Been the Temperature and Precipitation this Fall?

 Several folks have asked about this autumn.  Has it been drier and warmer than normal?

Let's check it out by considering a representative location:  Olympia.

Below is a plot of cumulative precipitation at this location from September 1 to yesterday.  Green is this year, and the brown line is normal (the climatological values).

September was close to normal, but October has been quite dry.

No wonder I have been able to bike to work without rain gear!

Temperature is shown below, with the blue bar showing the daily highs and lows and the brown band showing the normal range.  Red indicates record highs.  

September was very close to normal, and October has been modestly above normal.

But let's get a better historical picture.  

Below is a plot of the Sept 1-October 21 precipitation totals for the past 50 years at Olympia.  A trend line for the period is also shown.

This year's precipitation is low, but many years were lower

Interestingly, precipitation increased over the period, so you can't blame climate change!

The average temperature for the entire (Sept 1-Oct 21) period was very close to normal ( this year was the 25th warmest year out of 50 years).

However, this is evidence of long-term warming, with about a 2°F warming over the past 50 years, very consistent with warming found in many studies.

What about the outlook for the rest of the month?  

The excellent European center model is predicting cooler-than-normal conditions (blue) over much of the Northwest (except for NE Washington).

In contrast, the European center model is going for drier-than-normal conditions over the Cascades and Olympics over the next week.

Biking should be relatively dry for the remainder of the month.