Weather Blog

A persistent fog, but was it a record fog?

A persistent fog, but was it a record fog?
Space Needle hides in the fog on Jan. 21, 2013.

It's been a long time since Seattle has been in the fog for so long, but it might surprise you to learn we weren't that close to a record.

Seattle has spent a full week with dense fog at times -- defined as 1/4 mile visibility or less -- courtesy of strong ridge of high pressure that created a monster inversion over much of the Puget Sound region.

The 7 day streak ties for 5th longest all time with several other years. The record is 13 set during the "epic fog storm" of December 16-28, 1985 when the city had 13 straight days with dense fog at some point.

But what makes this stretch so memorable is not just dense fog for a few hours each morning, but for days on end with no relief in sight (or much else, for that matter.)

At one point during our week of fog, Seattle had a stretch of 80 consecutive hours Thursday through Sunday with fog at 1/2 mile visibility or less. The "break" in the fog lasted just 5 hours, and a new fog layer moved Sunday evening.

That layer was even thicker, rattling off another 24+ straight hours of dense fog -- this time 1/4 mile or less.

In fact, add it all up and as of 5 a.m. Tuesday morning, Seattle had spent only 6.5 hours of the previous 120 hours (five full days!) with visibilities greater than a half mile. I'm not sure that kind of consecutive-hourly-fog record is kept to know if we broke it, but let's just say we did for fun.

That foggy stretch was expected to end midday Tuesday with increasing winds finally scouring out the fog.

The wind is ahead of some rain expected Tuesday night. Lost in the fog (no pun intended) was the fact that it hasn't rained in several days in Seattle. Monday marks 11 consecutive dry days with Tuesday possibly going down as No. 12 depending on when the rain arrives.

Is that a record? No. Not even close. We'd have to get to 21 days set in December, 1985 (of which the 13 day fog storm is a majority.)

What about temperatures? It's been fairly chilly overnight! As of Tuesday, Seattle was at 13 consecutive days with a low temperature at or below freezing. That is also not a record... and not really that close. The record is 24 days set in 1946. We need to get to 17 to reach Top 5 status. Seattle will likely remain above freezing on Wednesday.

We get back to "normal" later this week so even though we didn't break any records, at least the foggy forecasts won't keep sounding like a broken record.