Historic July Rainstorm Fells Trees and Floods Roadways
The deluge of rain which beleaguered the Germantown area and entire Mid-Atlantic region for the last 24 hours is coming to an end. There may be some more showers rolling through the area on Saturday afternoon, but the main portion of the rare summer storm has moved off-shore.
The storm dropped a massive amount of rain in a relatively short period of time. According to the National Weather Service, Gaithersburg Regional Airport tallied 5.94 inches of rain from 7:00 am on Friday, July 28. The rainfall broke records at all three major airports, with Reagan National leading the way with 3.31 inches, BWI with 2.58 inches, and Dulles with 1.66 inches in the 24 hour period on Friday.
Locally, the Germantown Pulse weather station recorded 2.86 inches of rainfall between 10:30 am Friday and 2:30 am Saturday evening. All total, the Germantown area has received 9.14 inches of rain in July, according to the Pulse backyard weather station.
According to the Capital Weather Gang, this storm was perhaps a once in a lifetime event. “This kind of storm would happen once every 50 years, all else being equal. However, noting that it’s July and not January, we’re thinking it’s actually more like 1 in 100 years — maybe even longer.”
Naturally, the massive amounts of water sparked a flurry of flood watches and warnings throughout the area, and indeed many local streams and creeks have crested over their banks forcing the closure of area roads.
The Montgomery County Department of Transportation, Division of Highway Services reported that at one point overnight as many as 19 area roads were closed to either flooding or trees falling across them.
While the storms didn’t bring very heavy winds, the epic rainfall was enough to create situations where the ground became so weak trees could not hold their roots.
Indeed, the National Weather Service issued a Special Weather Statement regarding the dangers of trees falling. “Saturated ground from recent heavy rain is causing shallow rooted and weakened trees to uproot even in the absence of significant wind. Individuals driving or walking in wooded areas, especially those adjacent to creeks, rivers, streams, and lakes, should exercise extreme caution today,” said the National Weather Service.
Among the roads closed, at one point or another in the last 24 hours, due to flood waters or trees coming down were; Riffleford Road at the Great Seneca Creek, Peach Tree Road in Clarksburg, Blunt Road/Wayfarer Road between Germantown Road and Blunt Road, Game Preserve Road between Clopper Road and MD-355, and then again Blunt Road from Brink Road to Davis Mill Road; and New Cut Road between MD-355 and Houser Road.
The rain arrived earlier than expected. On Thursday, The National Weather Service had issued a Flash Flood Watch which was to begin at 2:00 pm on Friday, the rain started at about 10:30 am, and by noon many roads in the Germantown area were seeing the creeks and streams overflowing, many were passable, but waters continued to rise.
By midday, portions of Brink Road between Ridge Road and MD-355 had become a brown river of water flowing into Frederick Road. At large tree uprooted on Blunt Road/Wayfarer Road at the intersection of Watkins Meadow Drive, the tree was leaning on power lines and blocked the road.