Heavy Rain, Thunderstorms This Afternoon

Multiple bands of showers have moved across Southern New England this morning with over 0.25" already in a band from the Eastern half of Connecticut up into Worcester County.  The heaviest of today's rain is yet to come so expect a wet afternoon and evening.  The heaviest of the rain will fall in a couple of isolated strong to severe thunderstorms between 4-8 PM, mainly in Southeast Massachusetts and Rhode Island.

General Overview

The simulated radar and total precipitation model simulations that I (and all meteorologists) use to forecast these storms have had a "convective" look to them for days.  The high-resolution computer models we use, as well as real-time information about the atmosphere, are foretelling of some strong to severe thunderstorms this afternoon and evening.  This is not a widespread outbreak like it may be in the Mid-Atlantic but damaging winds in excess of 60 MPH, hail, and a brief tornado (waterspout) are possible.

SPC Day 1 Severe Weather Outlook

Why a tornado?  We have a triple point low and plenty of rotational energy available in the atmosphere.   The chance is very low, but it is not zero. 

WPC Surface Fronts/Precipitation Thursday 8 PM.  The Triple point is where the red warm front, blue cold front, and purple trough of low pressure meet.  The change in wind direction and the clash of air masses make this a favorable spot for severe storms.

 Of greater concern are strong thunderstorms taping the low-level jet stream which has winds of 70-80 MPH.  When transferred to the surface this would result in 55-65 MPH wind gusts, certainly strong enough to topple trees given the saturated soil.  As I type this, lightning strikes are showing up on radar near Narragansett Bay (aka better hurry up and get it posted).

NWS Radar Estimated Rainfall through 1 PM

The flood watch is still in effect.  Here is simulated radars for 3 PM and 6 PM.

13z HRRR Simulated Radar 3 and 6 PM (image Weatherbell)

Another inch of rain likely across Eastern CT, Central/Eastern MA, and RI.  Temperatures will steadily warm into the upper 40's/low 50's.  When the warm sector moves over SE MA temperatures will surge to near 60.  Hey where is the warm front at 9 PM?

13z HRRR 2 m temps Thursday 9 PM (image Weatherbell)

Some leftover showers/drizzle tomorrow before clearing for the weekend.