A slow moving low pressure system and a deep southerly flow from the Gulf of Mexico and then the Atlantic Ocean dropped heavy rain across the Eastern Shore centered on April 30th. Event precipitation totals averaged from 3.5 inches to 5.5 inches, with the highest amounts in Cecil County. This caused poor drainage and field flooding as well as flooding of some creeks, mainly in Cecil County. Creek flooding in parts of Cecil County were the highest since Tropical Storm Floyd in September of 1999 and persisted into the early morning on May 1st. The flow up the Chesapeake Bay coupled with spring astronomical tides associated with the new moon also caused minor tidal flooding. The steady rain began during the afternoon of April 29th and fell at its heaviest during the morning and afternoon of April 30th. The rain ended during the evening of April 30th.
Minor tidal flooding in Chesapeake Bay occurred during both high tide cycles on April 30th and the morning high tide cycle on May 1st. The highest tides occurred with the late afternoon and evening high tide cycle on April 30th. At Tolchester Beach, the highest tide reached 3.82 feet above mean lower low water at 842 p.m. EDT on April 30th. Minor tidal flooding starts at 3.5 feet above mean lower low water.
The heavy rain and tidal flooding were caused by the combination of a strong high pressure system that built over the Canadian Maritimes that initiated the onshore flow and a strong, but slow moving low pressure system. The low pressure system was located in northwest Missouri on the morning of April 29th. It moved northeast to near Chicago during the afternoon of April 29th. The low pressure system then became nearly stationary in southern Wisconsin as its cold front reached Ohio early on April 30th. Then a new low pressure system developed on the frontal boundary and was over Eastern Tennessee on the morning of April 30th. The low pressure system reached West Virginia during the late afternoon on April 30th as its warm front started to move through Delmarva. The low pressure system reached north central Maryland at 11 p.m. EDT on April 30th as its warm front reached extreme southeast Pennsylvania and central New Jersey. The low pressure system reached the Allentown, Pennsylvania area at 5 a.m. EDT on May 1st and then was absorbed again into the frontal boundary associated with the original low as it moved into New York State that morning. The steady rain ended as the low pressure system passed north of the Eastern Shore. But the formation of the second low pressure system and the passage of the warm front helped veer the winds from the east to the south and enhanced the surface flow that produced the tidal flooding.

Flood in CECIL, MARYLAND
From 01-MAY-14 00:00:00 to 01-MAY-14 00:07:00 (EST-5)
Location: CHESAPEAKE CITY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Big Elk Creek at Elk Mills had major flooding and was above its 9 foot flood stage from 415 p.m. EDT on April 30th through 107 a.m. EDT on May 1st. It crested at 12.65 feet at 815 p.m. EDT on April 30th. This was historically the 4th highest crest on record for the creek and the highest crest since September 16, 1999 associated with Tropical Storm Floyd. Event precipitation totals included 5.50 inches in Perryville, 5.45 inches in Elkton and 4.42 inches in Charlestown.