Flood in Androscoggin County, Maine

The Androscoggin River reached moderate flood stage on December 18th and remained in flood stage through the 20th. The flooding was the result of heavy rain and snowmelt, driven mostly by routed water from the western Maine Mountains where runoff was 8 to 10 inches between rainfall and snowmelt. Major flooding unfolded upstream in Rumford, with a dampening of the floodwave as it moved into Auburn. The flooding reached Center Street in Auburn, cutting off a main thruway. There were businesses impacted along North River Road near Center Street and along Riverside Drive. Flooding also occurred in Lewiston, where people were evacuated along Tall Pines Drive, Avon Street, Winter Street, Lincoln Street, North River Road between Stetson Road and Center Street, and Switzerland Road. Another primary thruway, Route 136 from Auburn to Durham flooded. Ferry Road in Durham was also closed due to flooding. In Lisbon, the flooding was isolated to Cedar Pond Road. Further upstream in Livermore, Goding Road near the Route 4 bridge was flooded, including Spruce Mountain Road.

Low pressure began organizing in the Gulf of Mexico on the 16th, setting record low sea level pressures as it traversed the Southeast through the 17th. Strong high pressure over the North Atlantic created a deep southeasterly flow that drew warm air into New England ahead of the approaching storm. By the time precipitation arrived on the evening of the 17th, temperatures were warm enough for rain everywhere except the highest peaks. Early on the 18th a shortwave trough was approaching from the Great Lakes and led to rapid deepening of the low pressure as it paralleled the Eastern Seaboard. Even as the center of the storm remained near Chesapeake Bay on the morning of the 18th, a strong low level jet had developed and winds began to gust in excess of 50 mph well inland from the coast. Damaging wind gusts continued into the afternoon. Hundreds of thousands of customers lost power due to falling limbs and downed wires. The anomalously warm air mass also led to intense rainfall rates beginning on the evening of the 17th, which continued into the 18th. Upsloping winds also enhanced precipitation along the southeast facing slopes of the mountains. Widespread 3 to 4 inches of rain fell, with isolated pockets of 6 to 8 inches. This fell on top of snow that was ripe from previous rainfall about a week earlier. An additional 2 to 3 inches of snow water equivalent was likely added to rainfall runoff. Numerous road washouts and road closures occurred due to flash flooding and fast responding small stream and tributaries. Widespread moderate to major flooding occurred along mainstem rivers. The storm destroyed 13 homes, caused major damage to 106 others, with an additional 65 homes receiving minor flood damage. Private damage was in the millions with public infrastructure damage of 20+ million being reported by FEMA.