Winter Storm — Knox, Maine

2024-03-23 · Knox, Maine

Event narrative

Snowfall rates in excess of 1 inch per hour in the morning led to snowfall totals ranging between 3 and 5 inches. Around 200 PM snow changed to freezing rain and began to rapidly accumulate near sunset. With around 0.75 inches glaze, power outages increased quickly after 800 PM, once the winds picked up with over 50 percent of customers without power during the night.

Wider weather episode

Early on the 23rd high pressure had built into New England, with its main axis settling across The County into Downeast Maine. Meanwhile low pressure was slowly organizing over the Southeast, lifting a warm front into coastal areas of the Northeast. Snow began very early on the 23rd as warm air advection aloft reached New England, and high pressure ensured that cold air damming kept temperatures below freezing across western Maine. By daybreak snow was moderate to occasionally heavy for most locations, and warning thresholds were being approached or eclipsed by midday. By mid afternoon on the 23rd the coastal front was steadily marching westward towards the coast. While temperatures aloft warmed above freezing, cold air damming remained strong and surface temperatures remained largely in the 20s. The result was a quick changeover to freezing rain along the coast. As the sun set ice accretion rapidly began and by early evening around one quarter to one third of an inch of ice had built up on power lines and tree branches. Power outages began to quickly increase in number around this time, peaking just after midnight. Low pressure deepened along the warm front south of Long Island, and as it swept east early on the 24th precipitation rapidly ended from west to east.

Source: NOAA Storm Events Database, event_id 1169360. Narrative written by the NWS forecast office that issued the report.