Why The Rain Won't Go Away
Cover Photo: Cheryl Thompson, Giles Co.
Lynchburg, VA - For weeks, the area has been drenched with rain and storms, leaving many asking when the rainy pattern will ever let up.
In Roanoke, for the past two Wednesdays in a row, major flash flooding has forced swift water rescues, closed roads with feet of water, and kept residents on edge who worry now every time it rains.
It rained officially in Roanoke for eight straight days, from June 29 through July 7. There was a quick break before the skies opened up again with a record setting 3.39" of rain on Wednesday, July 10.
A similar story can be told in Lynchburg. At the airport, it rained June 26 through June 28, again on June 30 through July 5. Then again on July 7 and July 8. More drops were recorded on July 10.
For the year now, Roanoke is 15.06" above normal, and Lynchburg stands at 7.63" above normal.
The wet weather pattern just hasn't been able to move out of the area.
The main reason is the jet stream. This river of air up in the sky serves as the storm track for systems across the world. For us, the jet stream took a huge dip toward the moisture-rich Gulf of Mexico late this June (see picture).
At the same time, a strong area of high pressure right off of the east coast, typically known as the "Bermuda High" this time of the year, set up shop... only the high wouldn't budge.
The end result has been a continuous flow of tropical air from the south into our area.
Tropical air can hold an extreme amount of water, and helps make ordinary thunderstorms produce inches of rain in no time (see the tropical air over us pictured left).
To be fair, the high has tried to build further west and shove the jet stream's dip and associated moisture to our west (it actually succeeded at this for the few days we didn't have rain around June 8), but ultimately, the pattern returned to its soggy state for our area again this week.
Another problem has been the humidity. Once the moist pattern set up and the very humid, tropical air made its way north into Virginia, there has been nothing to clear it out.
Despite fronts coming in from the north and west, trying to clear us out, they instead just fizzle out and actually become absorbed in the rainy pattern as they stall over us (pictured left).
Even the everyday "pop up storms" become potential flood makers in such humid air.
On July 3, an ABC 13 Viewer measured nearly six inches of rainfall in three hours at his house in the Southwest part of Roanoke County.
In fact, just Wednesday, most of the 3.39" of rain in Roanoke fell in under an hour.
It has become so soggy outside, that trees are falling over on their own because the wet ground can't support their root systems.
The ground is so saturated, in nearby Watauga County, North Carolina over the weekend, it only took a mere inch of rain to bring a nearby river to flood stage.
We will have one more day of flooding concerns Thursday as yet another front tries to make it through the area.
The good news is models show this front actually making progress through the area, and the pattern with the jet stream shifting enough for more sunshine by Friday into the weekend.
For more on the forecast, head to the ABC 13 Weather Center.
-ABC 13 Meteorologist Jamey Singleton