In September, when high temperatures soared into the 80s and 90s and overnight lows refused to drop below 70 degrees for days on end, we wondered if fall would ever arrive. Maybe summer would go straight to winter with no gradual, pleasant autumnal cool-down.

Granted, there were a few blissful weeks of fall weather in there; the first half of October was quite lovely with highs in the 60s and 70s. But overall, the past three months were very warm. In fact, it was the warmest fall season we know of in Washington, where weather records go back to 1872.

It marks yet another major warm weather milestone for the capital, all of which have occurred since 2010.

As the Capital Weather Gang’s Justin Grieser wrote last month, in an unchanging climate, we would expect a balanced ratio of warm records and cold records. But that’s not what we’re seeing. Since 2010, warm records have outnumbered cold records over 16 to one. We’ve seen 115 record warm temperatures and just seven cold records — and that doesn’t include significant events like “warmest fall” or last year’s unbelievably warm December.

These are the effects of a warming climate, scientists say, and they will continue as long as the global community uses fossil fuels as its primary source of energy.

Record autumn details

The average temperature in D.C., for September, October and November combined was 63.9 degrees. It was 0.6 degrees warmer than the previous record warm fall of 2007.

The season was one of the driest, too. Reagan National Airport only reported 4.16 inches of rain this season. On average, it would get just over 10 inches across the three months. It was the seventh driest autumn on record and it drove us into a moderate drought, which forecasters at the U.S. Drought Monitor say will be difficult to rise out of unless we get a series of storms in December that we’re just not seeing in the outlook.

Washington was not the only warm spot in the autumn. Almost the entire United States was warmer than normal.

The weather pattern was impressively consistent throughout the season: low pressure near the West Coast, and warm high pressure over the Eastern United States and Canada. This may be lingering influence from El Nino, and the global wind was quite strong in the autumn, along with the North Pacific jet stream.

Looking at just November, temperatures were 3 degrees above normal, ranging from an overall high of 83 degrees to a low of 32 degrees.

Precipitation in D.C. was a shocking 2.41 inches below normal. We only received 0.76 inches of rain last month, making it the ninth-driest on record, tied with November 1936. Interestingly, Dulles Airport and Baltimore were not as dry thanks to last-minute rains on Wednesday night. Dulles picked up a daily record with 1.31 inches and Baltimore recorded 0.97 inches.

Here is the list of all the records set in D.C., Dulles and Baltimore during the month:

D.C.

  • Nov 3: Record high temperature of 83 bests 80 from 1974.

Dulles

  • Nov 19: Record maximum snowfall of trace ties 1984.
  • Nov 30: Rainfall record of 1.31 inches beats 1.15 from 1967.

BWI

  • None

November forecast review

How’d we do?

The temperature forecast

I favored an average temperature around 50 (just above normal). Reality: 52.5.

The rain forecast

I forecast a range of 2.25 to 3 inches. Painful reality: 0.76 inches (Dulles: 1.77 and Baltimore: 1.51)

Summary review

Slight miss on temperature and BIG miss on precipitation. Let’s see if we can catch up in December!

Grade: C

Jason Samenow contributed to this post.