2016 became a year that people loved to hate. But when it comes to D.C. weather, there wasn’t too much to be angry about.
The biggest events of the year included a massive snowstorm, a freak February severe thunderstorm, a shocking flood, a scorcher of a summer and an autumn drought.
Rather than attempt to rank these events, I have put them in chronological order. The drought is listed last as it is ongoing. Perhaps it will become an event that makes the list two years in a row?
Blockbuster snowstorms don’t come along every year. But strong El Niños have been known for their big storm mischief, and the El Niño of winter 2015-2016 earned the apt moniker “Godzilla.”
Snow began falling during the midday of Jan. 22. Heavy snow fell through the night. It piled up and drifted into bigger piles.
As the 23rd dawned, a dry slot worked its way into the District, reducing the snow’s intensity for several hours, but western and northwestern suburbs continued to get clocked throughout the day. During the afternoon and into the evening, heavy snow swept back across the city as the storm began to pull away.
When all was said and done, a controversial 17.8 inches of snow was recorded at Reagan National Airport for the District’s total, enough to tie as the fourth biggest on record. Folks like me in the northwest part of the city recorded 2 feet. Baltimore picked up 29.2 inches, its largest snowstorm on record, and Dulles International Airport recorded 29.3 inches which ranked No. 2.
What made Snowzilla truly unique was that the District and most of the region picked up 80 to 85 percent of an above-average snowfall season in this one storm. Throughout recorded history, there is no other winter with that kind of stat. The closest was 1941-1942, also an El Niño winter, when 80 percent of the snow fell in one storm in late March. But that was a smaller storm, and the seasonal snowfall finished below average.
Freak February severe thunderstorm outbreak
Our usual peak thunderstorm season of June and July was fairly active. But arguably our most intense thunderstorm of the year came early.
Just over a month after the monumental snowfall from Snowzilla, a storm of a much different type hit the eastern half of the country.
The main story in the D.C. region was an intense rush-hour squall line. It caused numerous instances of wind damage thanks to gusts between 60 and 70 mph, dropped some big hail, caused street flooding and brought travel to a standstill.
The storm in the District was part of a two-day outbreak (Feb. 23-24) that produced 800 severe weather reports. That would be an impressive number in the spring. In February, it ranks as one of the biggest severe weather outbreaks on record for the month.
About five dozen tornadoes touched down over the two-day stretch, several of which caused fatalities, including in Virginia. Tornadoes were reported in our region as well, and even as far north as Pennsylvania, which is quite rare for winter.
A remarkable event.
Ellicott City Flood
The flood event of July 30 was isolated, but it produced the scariest weather imagery of the year in the local area.
Ellicott City, buried in a river valley to the southwest of Baltimore, was unfortunate enough to face a set of circumstances that put it in the bull’s eye of a thousand-year rain event.
That evening, 6.5 inches fell over the town; 5.52 inches in a 90-minute span. Statistically, there is less than a 0.1 percent chance of this occurring in any year, hence the 1,000-year rain event classification.
It was a typical summer day with high heat and humidity. As is also common in late summer, there was a fair amount of instability over the area. Additionally, steering winds aloft were not that strong. The high humidity levels and high instability overlapped across the region and sparked slow-moving thunderstorms.
The main complex of the evening set up just to the north of the city. Storms repeatedly moved from the Parrs Ridge area near Damascus toward Baltimore. In the middle lay Ellicott City.
Radar animation of the training rains over EC yesterday pic.twitter.com/xMkkJf5JNE
— TerpWeather (@TerpWeather) July 31, 2016
Training of storms — when they repeatedly move over the same area — is a frequent cause of severe flooding. While weather forecasters can generally predict the conditions that may cause this, it is usually hard to pinpoint exactly where it will occur until it is underway. Partly for that reason, many in Ellicott City were caught off guard. People dining and shopping were shocked to look out into a river where the road once stood.
While two people died in this event, it could have been much worse. Ellicott City is a place known for severe floods. This probably won’t be the last.
Since 2010, the heat seems to keep on coming.
Sure, we’ve seen a polar vortex or two, but the heat records have been hard to keep track of. After the 2010-2012 summers, even I was starting to wonder whether extreme heat was the new normal. We then saw a few cooler summers, but 2016 brought the heat back. And in a big way.
It was the third hottest summer on record, with a June through August temperature average of 80.6 degrees. This now means that of the top five hottest summers on record since the 1870s, four have happened since 2010.
As if that wasn’t enough to sell you that this was a big story, the summer was a late bloomer. Through Independence Day, the city had only seen five days at or above 90 degrees. This was well below average for the date, but then the flip switched.
From July 5 through the end of the month, 90 percent of days were 90 degrees or higher. July’s tally of 23 90-degree days fell just shy of the most (July 25, 2011) of any month on record. Then we did it again in August, with 23 such days being the most on record in any August. The two-month tally of 46 was the most in any July-August on record. August finished second hottest on record.
There were also four days at or above 100, including an incredible three in a row in August — a streak so long had not occurred since 1930. Overnight lows were toasty as well, with a record-tying seven 80-degree-or-higher lows, a big runs of 60-degree lows and the most 65-degree lows on record.
An emerging drought
In the District, we’re set to finish the year about eight inches below average on rainfall. A full 10 out of 12 months have seen below average precipitation.* March, October and November were all historically dry.
2016 brought the District only five days with 1 inch of rain or more, which ties for the fifth fewest on record since the 1870s. We have not seen a year with so few since 1980.
In the Mid-Atlantic as a whole, this is the longest-lasting and deepest drought the region has seen since at least 2012, and arguably 2010.
The situation is not yet dire, and it will take a considerable additional lack of rain to get there, but this might be a story to watch in 2017.
*December is of course not yet done, the total in the graphic is through Dec. 28.