Update: Stand aside everyone and let July 1st into the club! It did reach 90 degrees on Tuesday, finally getting July 1 with a record high at 90 or warmer.
Correction: I've been stating that July 10th also did not have a record high at 90 and above, but it turns out that is not the case. Most online NOAA records go back to 1948, but there are three years of records at Sea-Tac Airport from 1945-1948 that are not online. Turns out, July 10, 1945 hit 90 degrees. So, everyone's in the club!
We always pick on July 4th around here -- it's statistically the rainiest day of the month! And since it's arguably the most important outdoor day of the month, it gets a lot of attention when the weather doesn't cooperate.
But at least July 4th can say one thing: It's been over 90 degrees in Seattle before.
It's a claim that July 1st can't make. In fact, it's one of only two days in July never to hit 90. (July 10 is the other). Seattle has hit 90 as early as May 17th but never on the 1st of July.
That's not to say it hasn't tried, but it seems the date has some sort of heat shield. There have been seven times when either June 30 or July 2 have been 89 or warmer, setting up a softball down the middle of the plate for July 1st, only to swing and miss.
1965: June 30: 89. July 1: 82
1951: June 30: 90. July 1: 73 (hello, marine push!)
1995: June 30: 96(!). July 1: 87 (wah, waaaahhhh)
How about the other way?
1985: July 1: 74. July 2: 89
1991: July 1: 81. July 2: 89
1968: July 1: 87. July 2: 92
Perhaps its best shot was all the way back last year, when it was 93 on June 30 amid one of the most intense heat waves along the West Coast. Death Valley set an all time national June record with 129 degrees. Las Vegas tied their all-time record high of 117.
The heat surged up the West Coast, but the ridge managed to stay just enough to our east as to spare Western Washington somewhat. Had that ridge and ensuing thermal trough brought an offshore wind to our area, we could have hit triple digits in Seattle.
Alas, the calendar tuned to July and...Seattle "only" managed 89 degrees -- at least at Sea-Tac Airport (Boeing Field did hit 90). So 89 sits at the current record and July 1 is still turned away at the door at the annual July 90s club party. (Too bad. I hear the band 98 degrees is playing the gig this year.)
Could July 1 finally get in the club this year?
So, lo and behold, we have another moderate heat event this year building just in time for July 1. Forecast models suggest this is mainly a one-day event with cooling marine breezes returning for Wednesday.
Getting to 90 degrees in Seattle usually takes a few-day event to warm us up that much and we aren't looking at much of a springboard Monday with highs expected in the upper 70s (although look at 1985 up there). Most forecast models are suggesting mid 80s for Tuesday-- maybe upper 80s, but 90 looks elusive once again. We are forecasting 85 for Seattle.
But July 1 can ping their hopes on one model: The old "NAM" model, which is actually forecasting 90 Tuesday.
That model typically goes warmer than the others, which are nestled in around 86 but it's something. Also on board, the University of Washington "Probcast" model which says... 94 for Sea-Tac!
That seems way overdone, but it's some straws for July 1st to grasp at! Otherwise, July 1 will have to just be content to forego the party and go bowling with similarly shunned July 10th.