DAYS 1-5 (JUNE 30 – JULY 4)
The disturbance that I’d been eyeing for several days for Wednesday night to produce a passing shower and possible thunderstorm certainly did that, especially in northern MA and southern NH where a good batch of storms occurred. There was no severe weather, but many saw downpours and a good lightning show for a while late late evening. That cleared out later and is now gone, and the only speed bump in the next 5 days is a cold front passing through on Saturday with a shower and thunderstorm threat. Otherwise, we have lots of great early summertime weather in store for us. High pressure will bring fair weather today with lots of sun, few clouds, manageable dew points, and warm air – a great final day of June! High pressure shifts offshore on Friday and delivers the heat to our region, although the dew point will be slow to rise, so while it turns out to be a hot day, it won’t be oppressively humid. However, the humidity will spike more noticeably Friday night as a warm front slides across the region (really more a dew point boundary than a true air mass front). These types of boundaries can kick off showers and thunderstorms sometimes, and there is that chance later Friday night (mostly during the overnight hours). This will lead to several hours of more oppressive humidity through midday Saturday, and a little longer for southern MA, CT, and RI. A cold front will be moving into and across the region starting by midday and taking until evening to reach the South Coast region. While this front will be ready to deliver drier air, it will also trigger showers and thunderstorms which have the potential to be strong to locally severe. The exact timing of showers and storms for each location is uncertain obviously, but the general idea is that the threat will start by early afternoon in southern NH through central MA then progress east southeastward to the South Coast by the evening hours where it may linger for a while. Locations mostly north of the Mass Pike likely see improvement for any Saturday evening fireworks displays. Overnight, drier air will flow into the region, but it will remain muggy along the South Coast into Sunday morning before the drier air finally arrives there. Some guidance has showers lingering along the South Coast into the morning as well, but at this point I am optimistic these will have largely moved offshore and that Sunday will be a dry day region-wide with lots of sun, some fair-weather clouds, warm air, but much lower humidity than Saturday. And right now it also looks like the high pressure area that brings this weather for Sunday will hold its influence for Independence Day Monday with a sun/cloud mix (sun dominating), seasonable warmth, and fairly low humidity. Many outdoor activities and evening fireworks displays take place both Sunday and Monday, and the weather looks great for it all…
TODAY: Mostly sunny. Highs 78-85. Dew point lower 50s. Wind W 5-15 MPH.
TONIGHT: Partly cloudy. Lows 58-65. Dew point middle 50s. Wind WSW up to 10 MPH.
FRIDAY: Mostly sunny. Highs 88-95, cooler South Coast. Dew point upper 50s to lower 60s. Wind SW 5-15 MPH.
FRIDAY NIGHT: Partly cloudy evening. Variably cloudy overnight with isolated to scattered showers and thunderstorms possible. Lows 67-74. Dew point rising to middle 60s. Wind SW 5-15 MPH.
SATURDAY: Variably cloudy. A shower or thunderstorm possible early, then a passing shower or thunderstorm during the afternoon and early evening from west northwest to east southeast across the region, with any thunderstorms potentially strong to locally severe. Highs 85-92, cooler South Coast. Dew point rising to upper 60s to around 70 through early afternoon, then falling slightly especially in northwestern areas by late day. Wind SW 10-20 MPH except variable with potential strong gusts near storms, shifting to W from northwest to southeast later in the day.
SATURDAY NIGHT: Variably cloudy. Evening showers and thunderstorms possible, mainly South Coast. Areas of fog especially South Coast. Lows 62-69. Dew point falling to upper 50s north of I-90 but staying in 60s to the south. Wind W 5-15 MPH.
SUNDAY: Lingering clouds South Coast early, otherwise mostly sunny. Highs 80-87. Dew point middle to upper 50s except lower 60s South Coast early. Wind NW 5-15 MPH.
SUNDAY NIGHT: Clear. Lows 60-67. Dew point below 60. Wind W up to 10 MPH.
MONDAY (INDEPENDENCE DAY): Sun/cloud mix. Highs 81-88, cooler some coastal areas. Wind W up to 10 MPH but some coastal sea breezes possible.
DAYS 6-10 (JULY 5-9)
Two disturbances should move through the region with a west to northwest flow during this period bringing opportunities for showers/thunderstorms for relatively brief periods of time, and some variable temperatures but not straying that far from normal.
DAYS 11-15 (JULY 10-14)
Weaker westerly flow and more high pressure to the south should allow for warmth and somewhat higher humidity to be the rule but with limited shower and thunderstorm opportunities.