While a storm system moving up from the South will be past peak, the system may pack enough punch to bring locally severe thunderstorms and flash flooding part of the Ohio Valley and East Coast into Tuesday night.
**Flash flooding occurred in the Gaithersburg and Germantown, Md. area during the midday Tuesday. Flash flooding expanded to multiple areas north and west of Washington, D.C. and Baltimore during the afternoon. Thunderstorm winds damaged homes in the Anderson, S.C. area during the morning Tuesday.**
According to Severe Weather Expert Henry Margusity, "As an upper-level disturbance associated with the storms system lifts northward the right conditions could develop to produce a few thunderstorms with high wind gusts, hail and even a short-lived tornado."
The violent storm risk area extends from eastern Kentucky to much of West Virginia and central and southern Ohio and southwestern Pennsylvania during Tuesday.
Cities that could be impacted by the storms include Cincinnati, Dayton and Columbus, Ohio; Lexington and London, Ky.; Charleston, Huntington and Morgantown, W.Va.; and Pittsburgh, Pa.
Key to the potential of the storms is how much daytime warming occurs.
"If these areas remain cloudy much of the day, there may not be enough energy and rising air to get severe thunderstorms going," Margusity said. "Provided the storms do develop, atmospheric conditions indicate a fair amount of wind shear, which can lead to damaging wind gusts and perhaps a couple of tornadoes."
Because of cloud-cover issues, an large outbreak of severe weather is not expected, but rather only isolated severe storms.
Some of the storms bringing the severe weather may not have a great deal of lightning strikes associated with them and may sneak up on some locations as a result.
Other thunderstorms will affect the Atlantic Seaboard during Tuesday and a couple of these storms could be heavy and gusty in the I-95 swath from Florida to New York and part of the I-81 corridor farther west.
By heavy and gusty we mean there is not only the potential for damaging wind gusts, but also incidents of flash and urban flooding.
"These areas will be the warmest within the storm system's reach, but the main wind energy will be directed northward toward the upper Ohio Valley, rather than toward the East Coast," Margusity added.
While the storm system is weakening, it will have enough energy and moisture to bring areas of rain into the Northeast into Wednesday.
The combination of moisture from Erika and a non-tropical system will drench areas from Florida to the Georgia coast through the middle of the week.
A rapid shutdown of tropical activity and an end to hurricane season in early September is not likely this year, despite a strong El Nino.
Typhoons and building drought will impact more than one billion people in southeastern Asia this fall.
The calendar may have flipped to September but summer is not going anywhere just yet across the Northeast.
Tropical Depression 14-E developed several hundred miles southwest of Mexico on Monday and is expected to strengthen as it moves northward through the middle of the week.
Heat will be erased by an autumnlike air mass across parts of northern Europe.
Los Angeles, CA (1955)
110 degrees, hottest day ever in September. This mark was tied September 4, 1988.
Milwaukee, WI (1988)
Hottest summer on record. Six days of 100 degrees or greater and 36 days of 90 or above. Average temperature of 73.8 beat the old record of 72.8 set in 1921 and 1955. The normal average tempera- ture for a summer in Milwaukee is 68.3 degrees.
Washington Co., IA (1897)
Hail fell and drifted in piles 6 feet deep in Washington County.