BOSTON (CBS) – The entire eastern and southeastern part of Massachusetts is under Tropical Storm Warnings for Tropical Storm Elsa.
A flash flood warning was issued for the Boston area and the counties of Middlesex, Worcester, Norfolk and Bristol until 4:00 p.m. Friday.
CLOCK: CBSN Boston Live coverage of Tropical Storm Elsa
While Elsa will be quick by the afternoon, there are several reasons for concern in our area.
TRACK: Tropical storm Elsa
What to expect:
The heaviest rain will fall west of the route that covers most of the areas west of I-95. Until Friday noon there can be up to 5 to 6 inches of rainfall in parts of our region.
The strongest winds will blow east of Elsa’s Path, which will likely encompass the immediate South Shore coast and certainly Cape Cod and the islands.
In this zone there is a risk of tree and power line damage as well as numerous power outages. Wind gusts of 35 to 55 miles per hour are likely to be fair east of I-95. Further southeast over the extreme southeastern mass. and the Cape Islands, winds could blow 55 to 70 miles an hour from the south-southeast.
While we don’t expect major storm surges or coastal flooding with Elsa’s Passage, the seas get very angry with waves 10 to 20 feet just offshore, especially on our south-facing beaches along the south coast. Dangerous currents and sea conditions will exist for most of the day on Friday.
The heavy rain circulation directly connected to Elsa will last until the afternoon. The torrential rains will continue from time to time, producing 2 to 4 inches of rain, locally higher amounts of 5 to 6 inches.
This rain will fall in a short period of time, causing road and flash flooding, with some roads becoming flooded and almost impassable. It is never safe to drive through a flooded street.
The strongest winds (in extreme east mass, cape, islands) occur between 7 a.m. and 4 p.m. on Friday when Elsa’s center powers up our area. Again, south-southeast gusts of up to 55 mph are likely throughout this area, with the potential for some as high as 70 mph on the Outer Cape and islands.
When tropical systems pass near or above them, there is always an increased risk of severe weather, perhaps even an isolated tornado. This is something else we will be watching closely this afternoon.
The rain will decrease rapidly as the afternoon progresses from south to north and almost all of the rain structure will be in Maine after 1pm to 2pm. and speed quickly north towards Canada. The wind will remain gusty for a few hours along the coast, until around 4:00 p.m. to 5:00 p.m. before loosening.
We’ll get a quick clearing on Friday evening and apart from a few occasional showers we have a pretty nice weekend with temperatures close to or slightly above 80 degrees. Just what the doctor ordered after a very busy week of wet weather.
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