Sizzling in Seattle: City smashes record for hottest April day

On Monday, the temperature in Seattle skyrocketed to an astonishing 89 degrees, breaking the previous record for hottest April day by four degrees. The old record of 85 degrees was set April 30, 1976. Weather records in Seattle date back to 1894.

The record is shocking on several counts:

• It was 30 degrees above the average temperature for April 18 of 59 degrees, the biggest departure from average for any existing record
• It broke the previous daily record of 77 degrees (from 1962) by 12 degrees.
• It was 12 degrees hotter than the average high temperature during the warmest summer days (July 19 through August 16)
• It marked only the third time on record Seattle hit 80 degrees on back-to-back days in April (the other times were April 23 and 24, 1905 and April 29 and 30, 1976).
• It was hotter than the hottest day during the summer of 2011, in its entirety.

Seattle is forecast to warm to 85 degrees today, which would break the daily record of 79 from 1934.  It could well become the second hottest April day on record a day after the hottest day was established.

Assuming it hits 80 degrees day, it will mark the first time on record during April that it has hit 80 degrees on three days and the longest April streak of 80 degree days.

Monday not only marked the hottest April day in Seattle, but also in Olymia (88 degrees vs. old record of 87) and Bellingham (83 degrees vs. old record of 78).

A number of locations in northwest Washington surged above 90 degrees!

“Pretty safe to say [Monday] was the warmest April day on record in western Washington,” the National Weather Service in Seattle said.

Temperatures in the Pacific Northwest were as warm as anywhere in the nation, including southern California and south Texas.  It was eight degrees hotter in Seattle than in Miami.

University of Washington professor of atmospheric sciences Cliff Mass explained on his blog that a strong ridge of high pressure at high altitudes over the western U.S. set the stage for the unusual heat.

Closer to sea level, “there was southerly flow with enough of an easterly component to give some offshore flow that reduced the marine influence,” Mass said.

After today’s round of record heat, temperature will cool Wednesday into the 70s as winds start to come off the water. By Thursday and continuing through the weekend, skies turn overcast with daily shower chances. Temperatures return to more characteristic 50s and 60s.