DAYS 1-5 (JUNE 16-20)
The final full five days of astronomical spring span this forecast period, and we have some nice weather much of the time, with one interruption. We start with fair weather today as high pressure slides well south of us, across the Mid Atlantic Coast, while a quasi-stationary low pressure area sits in Atlantic Canada. After a cool start, it will warm to seasonable levels, but the coast ends up coolest this afternoon as a weakening westerly wind flow allows sea breezes to eventually develop – but a very nice day overall! Decorative cirrus cloud patches are visible in the northwestern and northern sky to start the day today, but in general we’ll see unlimited sunshine. More cloud cover will be present on Wednesday as a disturbance closes in from the west. This may trigger a shower or thunderstorm in western New England later in the day but I suspect none of that activity will survive to reach the WHW forecast area. However, clouds will thicken up ahead of a warm front Wednesday night with rain chances increasing overnight. Low pressure crossing the Great Lakes and heading for the St. Lawrence Valley will pull that front and its attendant rainfall through the region into Thursday morning before we emerge into the low’s warm sector. This is when we’ll see a spike in humidity and then have to watch for showers and thunderstorms as the low’s cold front approaches and passes through the region. Thursday’s shower and storm potential does have to be watched as there will be some ingredients for severe storms in place. However, this no longer appears as if it will be an optimal set-up for severe storms due to the lack of sunshine in the warm sector and also the best instability remaining to the west and south of the WHW forecast area. It still bears watching, however. Whatever showers and storms do occur will move out that evening as the cold front moves through and offshore. This sets up dry, breezy, but pleasant weather for late this week with a west to northwest air flow via Canada and the Great Lakes.
TODAY: Mostly sunny. Highs 77-84 except cooler South Coast / Cape Cod. Dew point upper 50s. Wind W 5-15 MPH, diminishing to under 10 MPH with developing coastal sea breezes this afternoon.
TONIGHT: Mostly clear. Lows 56-63. Dew point lower to middle 50s. Wind SW up to 10 MPH.
WEDNESDAY: Sun followed by clouds. Highs 76-83, coolest South Coast. Dew point rises toward 60. Wind S 5-15 MPH.
WEDNESDAY NIGHT: Mostly cloudy. Showers arrive overnight west to east. Fog patches form pre-dawn. Lows 61-68. Dew point 60+. Wind S 5-15 MPH.
THURSDAY: Mostly cloudy with early showers likely, then variably cloudy with potential showers and thunderstorms in the afternoon. Highs 76-83. Dew point rises to near 70. Wind SW 10-20 MPH, gusts 25-35 MPH.
THURSDAY NIGHT: An early shower or thunderstorm toward Cape Cod otherwise clearing. Fog patches evening. Lows 56-63. Dew point falls to 50s. Wind SW shifting to NW 5-15 MPH.
FRIDAY: Sun and passing clouds. Highs 76-83. Dew point near 50. Wind NW 5-15 MPH, higher gusts.
FRIDAY NIGHT: A few clouds, then clear. Lows 55-62. Dew point near 50. Wind NW up to 10 MPH.
SATURDAY: Sun and passing clouds. Highs 75-82. Dew point near 50. Wind NW 5-15 MPH.
DAYS 6-10 (JUNE 21-25)
Fair weather continues to finish the weekend as we welcome summer on June 21 (solstice 4:24 a.m. EDT). Wet weather potentials June 22 & 24 with fair weather June 23 & 25. No significant heat in sight.
DAYS 11-15 (JUNE 26-30)
Home stretch of June expected to feature a west northwest flow / progressive pattern with a couple shower and t-storm chances from passing disturbances, otherwise mostly fair weather and variable but mostly fairly close to normal temperatures.