Thursday’s 1°Outside Insights: Storm Usher In Changed Air for the Weekend

Today’s “deep dive” into meteorology is exactly that!  Matt Noyes explains the why behind the increasing risk for severe thunderstorms, and why parts of Northern New England, as well as Southern New England, are susceptible to flash flooding. Of course, these videos take you through the next several days so Matt covers the weekend, too!

Current Weather Overview

High pressure has been dominating the past few days, bringing heat and humidity. Now, a cold front is moving in from the north and west, bringing the potential for severe weather. The Storm Prediction Center has highlighted much of New England for scattered severe storms (yellow) and isolated severe storms (blue).

Severe Weather Threat

  • Primary Threat: Damaging straight-line winds.
  • Other Threats: Potential for rotating storms, hail, torrential downpours, and cloud-to-ground lightning.

Stay Informed

For updates, particularly with today’s storms, download our app from the App store or for Android see the logo at the top of our homepage banner at 1DegreeOutside.com. Keep notifications on to get alerts before the storm arrives.

Driving Factors

There are weak energetic disturbances in the atmosphere, which, combined with the heat and humidity, create conditions ripe for thunderstorms. A disturbance moving into northern Maine today will cool the upper levels of the atmosphere just enough to trigger storms.

Storm Motion:

  • Winds at 18,000 feet are steady at 30-40 mph, and storms should move from west to east at 35-40 mph.
  • This helps ventilate storms, allowing them to last longer.

Flash Flood Risk

The Weather Prediction Center has highlighted areas for flash flood risk. High precipitation amounts are expected in certain areas:

  • Northern Greens: Isolated 2-4 inches of rain.
  • Northern Maine: Isolated 2-6 inches of rain (e.g., Waterville, Lewiston).
  • Berkshires: Up to 5 inches of rain in localized spots.
  • Eastern and Central Massachusetts: 1-2 inches of rain, with a lower (but not zero) flash flood risk due to quicker moving storms.

Weather Changes Ahead

Friday:

  • Temperatures: Much cooler, generally in the 70s, with some areas still reaching 80s.
  • Wind: Northeast wind along the coastline, southwest wind at the South Coast, increasing the chance for showers.
  • Showers and Thunderstorms: Expected throughout the day, but especially in central and southern New England in the afternoon.

Saturday:

  • Northern New England: Cooler with clouds and showers.
  • Farther South: Drier, with a passing shower possible in the morning and a higher chance of showers later in the day.

Sunday:

  • Morning: Showers possible near the Canadian border and western New England.
  • Late Day: Disturbance brings increased chance of downpours and thunderstorms in the late day and evening.

Monday:

  • Leftover Showers: Possible throughout the day.