Heavy Rain in Maryland, May 8 to 12, 1998

A series of low pressure systems that passed through the Middle Atlantic States and then stalled offshore gave the Maryland Eastern Shore nearly five days of continuous rain from when it started early in the morning on Friday the 8th until it exited the state from north to south on Tuesday the 12th. Storm totals averaged between 2.0 to 3.0 inches. The highest storm totals were in Cecil County. The heaviest rain for most areas fell on the 8th. Overall there were few periods of heavy downpours and there were sufficient lulls of light rain or drizzle to keep most small streams within bankfull. Most of the flooding problems were confined to flooded basements, backyards and some poor drainage flooding. The worst reported stream flooding was when Carroll Creek flooded the parking lot of the Fredericktown Mall on Friday the 8th. The prolonged rain was not expected to damage crops, but postpone some of the planting because of the wet fields. Storm totals included 3.09 inches in Conowingo (Cecil County), 2.80 inches in Salisbury, 2.14 inches at the Baltimore -Washington International Airport and 2.00 inches in Federalsburg (Caroline County). A low pressure system heading toward the Middle Atlantic States was in the lower Ohio Valley the morning of the 7th. By the morning of the 8th, it moved into northern Indiana as a secondary was forming in Virginia. On the morning of the 9th, this secondary low was located about 285 miles eastsoutheast of Indian River Inlet, Delaware. But, it became trapped by a low at upper levels of our atmosphere and drifted slowly south through the morning of the 10th. Meanwhile, a large high pressure system started building into Northern New England. Yet another low pressure system developed over the Southern Plains on the 9th and was in the Tennessee Valley the morning of the 10th. On the morning of the 11th, two low pressure systems, one trapped under the closed low in the western Atlantic and the other just east of Charleston, South Carolina continued the wet onshore flow. These two lows merged into one by the morning of the 12th about 275 miles east of Cape Hatteras, North Carolina and remained nearly stationary through the 14th. The high pressure system over Northern New England slowly built south and brought drier air into the region and gave the area its first rain-free days of the month on the 13th and 14th.