Oregon Chapter
American Meteorological Society

| Home | Contact Us | Mission | Membership | Meetings | Current WX | Past WX | WX Pictures | Blog | WX Links |

Past Weather

Rainfall Record Falls

Wednesday, September 8th 2010  

Record setting rain fell on the Portland International Airport yesterday evening (Tuesday, September 7th) breaking an all-time record that stood since records began in 1940. Total rainfall measured at PDX yesterday was 1.55" which is a record for the day. However, what makes this an even more significant record event is the fact that 1.03" of the 1.55" fell in just 60 minutes last night between the hours of 8pm and 9pm, as heavy showers rolled through the metro area. The one hour total of 1.03" surpasses the previous all-time "one hour" record of 0.93" set just two years earlier, in May of 2008. Records at the Portland International Airport go back to 1940. This is a significant amount of rainfall by Portland standards, especially for this length of time. Vancouver, WA. and Hillsboro, OR. also set less significant daily rainfall records yesterday. Here are a few other notes on yesterday's record setting rainfall ---

* Only two calendar days during 2010 have measured more than 1.00" of calendar day rainfall at the Portland Airport. Oddly enough, those days are June 6th and yesterday, September 7th.

* Yesterday's rainfall was tied for the 7th wettest calendar day in the past decade, as listed below ---

11/6/2006 2.53"
1/1/2009 2.49"
1/31/2003 2.05"
9/30/2005 1.68"
12/2/2007 1.65"
12/3/2007 1.58"
12/13/2003 1.55"
9/7/2010 1.55"

* Yesterday was the 5th wettest September calendar day in Portland Airport history (1940-2010), as listed below ---

9/17/1969 2.23"
9/14/1996 2.03"
9/30/2005 1.68"
9/20/1982 1.56"
9/7/2010 1.55"

* The all-time wettest calendar day on record at the Portland International Airport (1940-2010) is November 19th 1996 when 2.69" of rain fell.

Steve Pierce
Vice President
Oregon Chapter of the American Meteorological Society (AMS)
503-504-2075 (Portland)
e-mail: stevejpierce@comcast.net