For This Afternoon: Sunshine will gradually give way to increasing clouds later this afternoon, especially across Central Mass. This is due to a developing low pressure system that’s located to the south of New England. Temperatures will be around 80 Degrees. Winds will be Northeast at 10 to 20 mph. Tonight & Wednesday: That low pressure system is expected to pass to the east of the Cape during Wednesday morning before hooking back to the northwest into Maine by Wednesday night. How close this storm system tracks to our area will dictate how widespread the rainfall will be later tonight and during the day on Wednesday. Some of the weather forecast guidance points to a too far east track, which would limit any rainfall to eastern Mass and the Cape. Other just as reliable weather forecast guidance forecasts a storm track that actually hooks this system into New Hampshire, which would lead to a widespread beneficial rainfall across the entire area. This is not an easy forecast at all At This Point, My Thoughts Are That Rain should first overspread Central Mass just after midnight tonight and spread westward into Western Mass around sunrise or so Wednesday morning. During the day on Wednesday, on and off rain looks quite possible throughout the day. The rain looks to come to an end by late in the day. As for possible rainfall totals – This is a very tough part of the forecast and has a high degree of uncertainty. Some data points to widespread rain totals of one half of an inch to one inch across the entire area. Other data points to less than one quarter of an inch across the entire area. My thinking is that the least amount of rainfall looks to occur across Western Mass with around one tenth of an inch possible. Across Central Mass, rainfall totals may amount to between one quarter of an inch (0.25”) and one half of an inch (0.50”). Low temperatures tonight will be near 60 Degrees. High temperatures Wednesday will be near 70 Degrees. Winds tonight will be Northeast at 10 to 20 mph. Winds on Wednesday will be North at 10 to 20 mph.