MEMA: Multi-Impact Rain/Flooding/Icing Event Friday/Saturday
The NWS has forecasted a multi-impact rain event Friday into Saturday. Heavy rain is expected to overspread the region Friday afternoon and evening and continuing into Saturday morning. Storm total rainfall amounts of 2 to 3 inches, and up to 4” in some areas are forecast over the entire region. Heavy rain combined with rapid snow melt will result in the possibility of some river and stream flooding along with the potential for isolated ice jam flooding on rivers (except Cape Cod & the Islands). The heavy rainfall combined with snow clogged storm drains may also result in significant urban/street flooding and flooding of low-lying/poor drainage areas. The heavy rain and associated flooding has the potential to impact the Friday evening commute. Strong 45-55 mph wind gusts late Friday into early Saturday could lead to a few downed limbs or small trees; isolated power outages are possible. There may be periods of dense fog on Saturday morning as well. As the heavier rain ends Saturday morning, temperatures will begin to drop from west to east, and they will rapidly dip below freezing during the afternoon and evening on Saturday, potentially resulting in flash-freezing. As the temperatures fall across the region, black ice may develop and any ice jams on rivers may freeze Saturday night and Sunday. This may cause hazardous travel conditions as well as extended river flooding.
TIMING
Friday through Saturday: rain and flooding
Saturday into Sunday: cold temperatures, refreezing and icing
THREATS
Elevated Flooding Risk (rivers, streams, low-lying and poor drainage areas)
Freezing rain and/or flash freeze
Dense fog
Strong and Potentially Damaging Winds
PREPAREDNESS & SAFETY INFORMATION
• Flood Safety and Preparedness Tips are available at: https://www.mass.gov/service-details/flood-safety-tips
• Elevate items stored in the basement and other low-lying flood prone areas of homes and businesses to minimize damage from flooding. If you have a sump pump, check that it is functioning properly.
• Clear snow and ice from street catch basins and storm drains to prevent or reduce street flooding.
• Avoid parking vehicles in low-lying areas or areas prone to flooding during heavy rainfall.
• Don’t drive through flooded roads. Remember the phrase “Turn Around, Don’t Drown!”
• Safely remove any remaining piles of deep snow from flat and low-pitched roofs. If safe to do so, clear ice and snow from drains on flat roofs.