WeatherWatcher: Arctic Blast of November 1955

Brother and sister Jarvis and Pat Erickson, children of the Butzke pioneers, 
learn to skate on Echo Lake circa 1955.

Vicki Michels, webmaster for the Echo Lake Neighborhood Association, reminded us that there have been times when Echo Lake froze hard enough for ice skating and the ELNA website has the photo to prove it!

Vicki has, with the assistance of Vicki Stiles at the Shoreline Historical Museum, created a large section on the history of the Echo Lake Neighborhood, which can be seen on their website.

Weatherwatcher Carl Dinse got curious about the actual date of the photo and started researching. The following is what Carl discovered.

By Carl Dinse

Another time when Echo Lake was frozen over completely was possibly November 1955. The above photo is estimated to have been taken that year. I had to do a bit of digging through records from Sea-Tac Intentional Airport, which is what the entire Seattle region uses for their official climate record.

The only significant freeze I could find was November, where two nights in a row the low temperature was in the single digits at Sea-Tac. Typically Shoreline reaches slightly colder than Sea-Tac, but this is the closest climate record station I could find to Shoreline for 1955.

Compared to our most recent bout of Arctic blasts this winter, the one in 1955 only lasted a week, and didn't start with much snow, but ended with a respectable snow event as warming started. November 10, 1955 temperatures at Sea-Tac started to drop with a low recording of 36°F and a rainfall of 0.16 inches (could have been a wet snow too that didn't accumulate). November 11th the temperature cracked a high of 38°F before plummeting into the teens. A total of 1.4 inches of snow was recorded that day at Sea-Tac.

For November 12th - 17th temperatures remained below freezing, setting all time records that have yet to be broken today for coldest temperatures in November.

Low temperatures:
November 11th: 15°F
November 12th: 13°F
November 13th: 14°F
November 14th: 9°F
November 15th: 6°F
November 16th: 21°F
November 17th: 23°F

Here's the temperature graphs and precipitation graphs reconstructed from Sea-Tac compared to historic average:

Data from Sea-Tac International Airport station (Seattle's climate record station).

Data from Sea-Tac International Airport station

Here's the precipitation graph for November 1955:

Data from Sea-Tac International Airport station.

Below is the Daily rain events graph, helps illustrate when large storms moved through:

Data from Sea-Tac International Airport station.

The arctic blast ended with what appears to be an atmospheric river or "Pineapple express". On November 17, 1955 4.6 inches of new snow fell as temperatures started rising, before changing over to rain. On that same day 0.35 inches of rain was recorded (some may have been snow melt off). November 18th had 1.28 inches of rain -- classic signature of an atmospheric river with temperatures getting back to near 50°F.