Five years ago, Washington braced for perhaps its most memorable snowstorm in modern times. It was named Snowmageddon, and it paralyzed the region with 18 to 32 inches of snow, ranking among the top five largest snow events in 144 years of records.

Remarkably, this well-forecast storm was the second snowstorm to rank among Washington’s top 10 biggest in the 2009-10 season. “Snowpocalypse” had buried the city in December.

But don’t call us a snow town …

Before the winter of 2009-10, almost no one would claim D.C. was a particularly snowy place.

Sure, there had been some big winters recently, like 1995-1996 and 2002-2003.

Both of those winters — and similar ones of days past — were largely defined by one major storm and several moderate ones. By that logic, the December 2009 Snowpocalypse was the main event of the season and area snow lovers would be left having to recall it for years to come.

Then came the end of January and the beginning of February 2010, when it sure seemed like the D.C. area had been relocated much further north, to a place like interior New England.

The looming big one

As the Feb. 2 to Feb. 3 snow event — a moderate snowstorm in Washington most seasons but almost forgotten in 2009-10 — departed, ominous signs of a much larger system were growing stronger by the hour. Snow lovers across the region began to collectively hold their breaths.

A slow melt of the roughly 10 to 15 inches of snow that fell from Jan. 30 to Feb. 3 would be short on time to fully disappear before the next onslaught. In many places, there was still substantial snow cover when Snowmageddon began. It is not often that snow accumulates on top of existing snow cover in D.C.

During the lead-up to Snowmageddon, an enormous conglomeration of moisture with roots in the tropics traversed northern Mexico in the continued active, and El Nino-enhanced, southern jet stream. Similar to the December storm, low pressure emerged around the Texas coast and moved to a position near Louisiana, where it dropped three to four inches of rain.

From the Gulf of Mexico, the center of the storm transitioned to a position off the southeast U.S. coast and tracked northeast to just off the North Carolina and Virginia shore by the morning of Saturday, Feb. 6.

Reminiscent of the December snowstorm — Snowpocalypse — the system was blocked from continuing too far north by cold high pressure in Greenland that also helped funnel cold air into the D.C. area during the course of the event. Instead of quickly passing by and heading north up toward New England, the storm slowly drifted east while pummeling the Mid-Atlantic.

Thanks in part to several similarities with the December storm, the low pressure and extreme snowfall produced by  the Feb. 5 to 6 snowstorm were exceptionally well predicted as far as winter events go.

The plume of moisture that dipped into the deep tropics only made forecasters more confident that a major event was on the verge of unfolding in and around D.C. A theme of 2009-10 — increasing snow forecasts as the storm neared — came to pass yet again with this event.

Snow attack

An expansive area of light snow moved into the D.C. area on Friday. In anticipation of the storm’s arrival, most businesses, schools, and the federal government closed up shop early. In prior days, grocery store shelves had been obliterated of goods.

Thanks to another major snowstorm on Tuesday and Wednesday, the soonest many offices and schools would reopen was one week later.

Initially, marginal temperatures near and just above freezing kept most accumulation to grassy surfaces or the coldest locations in the western suburbs. As the sun set on Friday, the snow’s intensity picked up, while convective bands (similar to heavy rain patterns associated with thunderstorms) began to push into the area around the developing low pressure. Colder air at high altitudes, being continually sent in from the north by high pressure in Canada, made this another somewhat rare storm in which almost all the precipitation fell as snow — rather than a wintry mix — in the Washington area.

Periods of heavy snow, some accompanied by obscured flashes of lightning and muffled rolling thunder, continued across the region late Friday evening through Saturday. Blizzard warnings were extended from the eastern shore back toward the west and into the District on Friday night. During the same period, Dulles Airport reported heavy snow every observation from 6 p.m. on Friday until 8 a.m. on Saturday.

The storm came in two rounds for the D.C. area and points east. The first round was heavy and wet. The second round — caused by upper-level energy swinging across the region from the west — also fell heavily, but it was drier and fluffier as temperatures dropped. Most areas came close but did not quite achieve official “blizzard criteria” (sustained winds of at least 35 mph) except for several locations near the coast.

How Snowmageddon stacked up

The storm, named Snowmageddon by the Capital Weather Gang community and picked up by national media, and later President Obama, dropped very significant snowfall across the entire Washington metro area. In most places the snow was chock-full of water content thanks to the tropical feed of the first portion of the storm. The storm likely rivaled the snowfall production of any other major snowstorm in recorded history locally.

In addition to ranking No. 4 all time for D.C., with 17.8 inches accumulation, the event ranks No. 2 all time at the current observation location (Reagan National Airport). Much of the city reported totals in the 20 to 24 inch range, with the highest numbers located in a band just north and west of the city.

Dulles airport recorded an incredible 32.4 inches. Places near there such as Leesburg, Va., fell just short of three feet, with 34.5 inches reported. Spots near Baltimore, through the northern D.C. suburbs and out toward the western D.C. suburbs received anywhere from 24 to 36 inches.

Regional spotters also reported as much as two inches or more of liquid equivalent water content in the snow, ranking Snowmageddon at the top of regional winter storms in that regard as well. The only major winter storms in D.C. history to drop more liquid equivalent in the city itself were the Knickerbocker storm of 1922 (No. 1 all time) and the great February 1899 blizzard (No. 2 all time).

Snowmageddon undoubtedly either reached maximum potential for the region or close. Those who saw the best continual banding are unlikely to see another of that caliber anytime soon if history is any guide. When the totals from before and after were added in, the 10-day to two-week period easily became the snowiest on record in many spots.

Local and regional aftermath

Because of the sheer quantity of snow, the aftermath of the storm was as challenging as it gets in the area despite occurring primarily on a weekend.

In addition to the normal slow-going tasks of clearing streets, rails, runways and sidewalks of snow, the water-laden nature of the event caused numerous trees and power lines to fall. At the maximum, power was out for about 200,000 people in the broader metro area, and it would be at least mid-week before it returned for many. Unfortunately for area football fans awaiting big parties, the Super Bowl fell during that window.

Trees were not the only casualties. A hangar at Dulles Airport collapsed under the weight of the snow, as did several churches and firehouses across the area. Other facilities such as schools and businesses with flat-top roofs faced either partial or full roof collapse as well. The melt and freeze cycle that went into the following week also caused ice-damming issues that resulted in building damage, not too common for the area.

The D.C. Metro system was hit hard. Above-ground train service was suspended at 11 p.m. Friday. Bus service was stopped at 9 p.m. the same evening, and remained closed through the day Saturday and in “snow emergency” mode with limited operations through Monday. Some above-ground stations returned to service by Tuesday morning, while other lines (including many Blue Line stations) closed into and past Tuesday with the next storm bearing down.

All flights on Saturday from National Airport were canceled as were most flights at other local airports, with the main exceptions being international flights due to land during the storm. All area airports remained down through Sunday and even into Monday before slowly coming back into service, first with arrivals then with full operations.

With estimates of 500,000 tons of snow to clear in Virginia alone, snow plowing operations focused on primary roads and highways before targeting secondary thoroughfares and finally neighborhood locations. The first two objectives were not completed until late Sunday and late Monday, respectively. As neighborhoods began to see clearing operations on Tuesday, rumors of the next storm grew larger.

In many locations there was simply more snow than places to put it. Some neighborhoods and subdivisions (as with author Kevin Ambrose’s residence in Oakton, Va.) would not see a plow until the second storm had come and gone, about a week after it all started.

Snowfall removal budgets were strained early and overtopped before the end of the season. Just for the first major snowstorm storm in December, D.C. used two-thirds of its annual budget. With several other smaller snow events before Snowmageddon, Maryland, Virginia and D.C. had already spent more than their annual budgets called for.

In many areas, special construction equipment had to be brought in to remove the snow, such as front loaders, bulldozers, and bobcats.

The federal government along with numerous area businesses and schools remained closed into the following week as temperatures stayed in the chilly teens and 20s at night to low 30s during the day, allowing for little if any melting to help efforts.

Despite the storm’s crippling effects, there was plenty of fun to be found across the region. Sledders hit their favorite spots, including Capitol Hill, as well as numerous other hilly streets and parks. Snowball fights cropped up across parts of the city, with perhaps the largest a 2,000 person melee in Dupont Circle. Despite the near halt to normal everyday life, the beginning of “snow week 2010” was taken in stride by many.

Still not done!

By Monday a storm expected to begin late on Tuesday and last through Wednesday was looking more and more intense on computer guidance, and local forecasts called for five to 10 inches of additional snow.

One of the most powerful northern jet stream storms of the winter was expected to collide with yet another piece of El Nino’s moisture to create what would become a true blizzard across most of the area and cap off an incredible period of snow in the Washington region.

That anniversary is right around the corner …