Metro Boston, North Shore and Metro West: Thursday provides another day of heat and oppressive humidity as we remain entrenched in a tropical air mass. Speaking of the tropics it appears that Tropical Storm Arthur will be upgraded to a category one hurricane today as he brushes the outer banks of North Carolina later tonight and early on Friday.
Wednesday was incredibly humid with dew points climbing into the low 70s across the area. Combine that with temperatures into the low 90s for many of us and the heat index, or real feel temperature, was in the mid 90s. As expected showers and thunderstorms developed to our west and northwest with some severe weather developing within some of the thunderstorms. Most of the heavy weather stayed west of the Route 495 corridor late yesterday afternoon and by evening the severe weather had significantly diminished there.
With Arthur to our south and a cold front to our west the tropical air mass continues to overrun the region with very humid conditions and warm temperatures. It will not be as warm on Thursday but the humidity levels will remain very uncomfortable. Expect a mostly cloudy day on Thursday with occasional peeks of sun through the morning. Then, a chance of scattered showers and thunderstorms in the afternoon. There is the potential for locally heavy downpours. Local flooding of low lying and poor drainage areas is likely within any of these downpours. Severe weather alerts could be issued as the day progresses so be aware of this potential, especially if you will be outdoors. High temperatures in the low to mid 80s. Lighter winds, mainly south to southwest at 5 to 15 mph.
The chance for showers and storms continue overnight with the focus for more organized bands of showers later at night, probably after midnight. Low temperatures stay near 70 degrees with another uncomfortable night ahead. Winds should stay light out of the south and southwest.
Arthur’s current forecast track, although still somewhat uncertain, takes the storm southeast of our area Friday night and well to our east Saturday. Meanwhile, the cold front to our west will move slowly across southern New England during Friday and will be offshore Friday night. With moist air continuing to stream into the area it remains a good bet that showers and thunderstorms hang around on Independence Day and night. It will not be as warm with highs nearing 80 degrees but the sticky conditions remain in place. Once the front moves offshore the humidity becomes tolerable Friday night. Expect lows to cool down to the low and mid 60s. Winds turn northwest and this is a sign of improving weather for the weekend.
High pressure takes over for the weekend. A shower is still a possibility across the coastal plain on Saturday, otherwise the weekend looks to be partly to mostly sunny with highs near 80 Saturday, mid 80s Sunday. Overnight lows a very comfortable upper 50s to low 60s Saturday night, mid 60s Sunday night. Much lower humidity throughout the weekend.
Warm and sunny weather prevails into Monday with highs well into the 80s.
Showers are a possibility later on Tuesday.