Forecast discussion: A strong high pressure ridge offshore helped bring more moisture into our atmosphere today, as winds begin to turn away from the east and southeast. We will see one more night of partly cloudy skies in Boston, although the humidity will be quite high. With dewpoints in the upper 60’s, it will be a difficult night to sleep without air conditioning.
The worst of the heat and humidity will be on Wednesday. Despite just partly sunny skies, temperatures will reach the lower 90’s. We only reached 82 degrees in the capital city as of writing this report on Tuesday afternoon. The cooler temperatures were due to easterly winds coming off the ocean. Winds will be coming from the southwest on Wednesday.
The cold front will be making its way from the Great Lakes moves into our area by the late afternoon. We may even see an isolated shower or thunderstorm during the evening commute. However, by sunset, we should see scattered showers and thunderstorms roll through the state. The precipitation should come to an end by early Thursday afternoon.
As we move past Thursday night, a new high pressure system will bring mostly sunny skies, but cooler conditions. Again, we will be seeing some colder Canadian air move into New England, thanks in part to northeast winds. High temperatures for the weekend appear to be only in the upper 70’s to lower 80’s.
However, we are at the risk of seeing seven straight Sundays without precipitation come to an end. The computer models are seeing a scenario where a low pressure system centered over the Ohio River Valley brings showers into Southern New England. This low will be slow moving, so we would see scattered showers and thunderstorms all of Monday and into the late afternoon on Tuesday.
Meanwhile, Tropical Depression Two was located at 12.9N 49.6W, or 800 miles east of the Lesser Antilles, as of 5 p.m. EDT. Maximum sustained winds are at 35 mph, and is moving west at 18 mph. The forecast from the National Hurricane Center only gives two a lifespan of 48 hours. There is too much dry air surrounding the system to keep it organized. Along with increased wind shear, there is the chance the system will dissipate even sooner.
72 hour forecast:
Tonight: Partly cloudy and humid with a low of 71. The coastline will most likely see patchy to dense fog.
Wednesday: Increasing clouds, hot and humid. Scattered showers and thunderstorms may arrive by the start of the evening commute. We will see a high of 92 with south-southwest winds of 13-16 mph. Some thunderstorms may contain gusty winds and heavy rain.
Wednesday night: Scattered showers and thunderstorms after midnight with a low of 70. Winds will come from the west-southwest at 4-7 mph.
Thursday: Scattered showers and thunderstorms end by the early afternoon with a high of 75.
Thursday night: Partly to mostly cloudy and cooler with a low of 61.
Friday: Mostly sunny with a high of 80.
Friday night: Partly cloudy with a low of 64.
Saturday: Mostly sunny. Highs 81-84, lows 65-68.
Sunday: Mostly sunny early, with increasing clouds and showers by 6 p.m. Highs 80-83, lows 67-70.
Monday: Cloudy with scattered showers/thunderstorms. Highs 77-80, lows 66-69.
Tuesday: Showers end by the late afternoon, but staying mostly cloudy. Highs 78-81, lows 65-68.