How unusual has been this month's fog event?

A  lot of folks have told me that they never experienced a fog event like this before in Seattle.  Others suggested it is unique for October.   Personally, I can not remember anything like this in October for many years.

But we need better, more quantitative, answers and there is no one better to ask than the individual I call Dr. Fog, a.k.a. James Johnstone, a local scientist that was worked for years on the West Coast fog and low ceiling problems.  This guys specializes in low clouds.

Examining Seattle-Tacoma Airport data, Dr. Fog found all the hours since 1951 for October 1-23 with the cloud ceiling (the height of the bottom portion of the cloud deck)  below 400 m (1300 ft) , thus representing situations with either fog or low stratus.  Depressing stuff.

By this measure, 2013 was the third worst October period on record in terms of average number of hours per day with such low ceilings:

1988:  10.0 hrs/day

1986     7.8

2013     7.4

Here is a plot of the situation in time:

So, this October was only the worst in 25 years!   I feel better already.  But for those less than 25 years old or folks living here for shorter periods, this IS the worst they have experienced.

Let's compare 2013 against 1988 using other graphics provided by Dr. Fog/Johnstone.  1988 had considerably more hours of low ceiling than 2013, but we had more low ceiling hours during the middle of the summer.

 The Victoria Times-Columnist also noted that the past period is the worst since the foggy times of 1988 and 1986.

A company called Weatherspark has some nice summary graphics. Here are their hour summaries of weather conditions for 2013 and 1988.  Grey is fog, green is rain.

First, 2013.  Big dose of fog the last few weeks. But no rain.

1988.  More fog.  Plus rain mixed in. (note this figure goes to the end of October).  The implies they could not escape as easily by ascending into the mountains.  MUCH worse.  During the past few weeks, you all knew you could escape the dismal low clouds with a short drive or climb.

Anyway, I hope everyone is feeling better....1988 was worse.   But we did experience the most foggy two weeks in October since 1988.  And keep in mind that October is fog season in the Northwest.

Tomorrow it is will all change as a strong trough moves through form the northwest.

 Dr. Johnstone's Home