Today's rains could pull us out of a drought but could also produce damaging winds, power outages and flooding.
With eight of the past nine months drier than average, September's deficit of 2.5 inches could be righted, as 2-4 inches are expected to fall into tomorrow, with as much as 5 inches in some locations. That would make September our first months with above-average rain this year, says NBC4 meteorologist Tom Kierein.
The storms could produce strong winds with very heavy rains, and some power outages are possible. It could continue into tonight and even into tomorrow's rush hour, which is unusual.
A flash flood watch is in effect for the area until 8 a.m. Tuesday.
The National Weather Service issued a flash flood warning for western Howard County and eastern Montgomery County in Maryland until 4:15 p.m. A flash flood warning for Carroll County, northwestern Howard County and Baltimore County in Maryland expired at 4:30 p.m.
Runoff from heavy rainfall will flood small creeks and streams. Low-lying areas are subject to flooding.
Motorists are reminded not to drive over roads covered by water as the depth and current may be hard to detect and could be too great for safe crossing. Most flood deaths occur in cars.
A coastal flood warning is in effect until 5 p.m. Tuesday for Anne Arundel and Baltimore counties. Water levels in the northern Chesapeake Bay have risen a foot-and-a-half to two feet above normal, which means moderate coastal flooding is likely with the next high tide. High levels are expected to continue Tuesday. Coastal residents should watch for rising water and prepare to protect themselves and their property.
A coastal flood advisory was issued for overnight, the National Weather Service said, and a watch will be in effect Tuesday morning through Tuesday afternoon. The advisory for St. Mary's and Calvert counties in Maryland begins at 6 p.m. and continues until 6 a.m.
Tornado warnings were issued for east central Carroll County and west central Baltimore County in Maryland until 1:30 p.m. A warning for central Howard County expired at 12:45 p.m.
The fundamental weather change began Saturday evening, but what it really means for us is no more heat waves. Saturday marked the 67th day this year with a temperature of 90 degrees or higher, tying with 1980's record. But we shouldn't have any more.
By noon tomorrow, the sun will be back, with a high of 80. More rain is expected Wednesday night into Thursday. Seasonal temps will continue into the weekend, with the weather actually beginning to feel like fall.
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