The Washington PostDemocracy Dies in Darkness

Washington has now hit 90 degrees or higher 50 times this year, a rare milestone

More than seven weeks of 90s are in the bag.

Temperatures remain in the mid-90s around sunset on a mid-July evening. (Angela N./Flickr)

Today’s the 50th day this year to reach 90 degrees or higher in Washington, which is 14 days more than the annual average of 36 days.

Hitting this mark pushes the city on the list of elite years for 90-degree days in recorded history. While it is true summer is waning, there are probably at least a handful more hot days to come.

For some quick perspective, to date (Aug. 21), there are only three years with more 90-degree days over the 148 years of records for Washington (dating to 1872). As recently as 2010, there were 54 such days at this point in the summer.

Only 12 percent of years in their entirety have seen more overall 90-degree days. If 90-degree day number 50 is our last — and I’d wager it’s not — then it would tie for 19th most on record.

All but two of the 19 years that reached 50 90-degree days failed to get to 60 days. Reaching 60 days would be enough for third most on record, with several years tallying 59. For now, based on long-range forecasts, 60 seems as though it would be difficult to reach, if not impossible.

2010 and 1980 posted the most 90-degree days on record, both tallying 67. While we are still ahead of the pace of 1980 this year, it was a summer known for its exceptional runs of late-season heat.

We piled up most of our 90-degree days this year when you would expect — during what are historically the hottest weeks of the summer. From June 26 to present, we logged 40 90-degree days, only two behind 1988, which posted the most such days during this stretch.

Many of our 90-degree days this summer were hot but not exceptionally hot, only hitting the lower end of the 90s. But the string of days topping 95 degrees this past Sunday through Tuesday has pushed the city’s count of days hitting at least 95 degrees to 11. That is right around the current average of 12 95-degree days per year.

Once we get past Thursday of this week, there appear to be few to no 90s on the near horizon. However, given how persistently high pressure over the Atlantic has blocked cool downs this summer, it is too soon to say we’re with 90s. Early September could bring another run.

The city averages about six more 90-degree days through the end of the season. Odds are quickly falling for them on any given day, with only three on average in September. But in 1980 there were still 14 90-degree days on the way, which is the most on record for the stretch that remains.

Washington’s average final date of 90 or greater comes around Sept. 11. In the 2000s, there have been four years that delivered a final 90 or higher in October. The latest one on record came when it reached 90 on Oct. 11 in 1919.