Forecast discussion: A low pressure offshore helped bring showers and light rain during the overnight early Saturday. Then, we had scattered showers for most of the day. Right now, we are awaiting a second surface low to our west to pass through Southern New England Saturday night. We will see scattered showers, with the chance of a passing thunderstorm. The second low will move offshore by the afternoon, ending our scattered showers. However, any sunshine may help the atmosphere create isolated showers Sunday afternoon. We will finally see some starlit skies Sunday evening.
A high pressure ridge coming down from eastern Canada will give us mostly sunny skies on Monday, with temperatures near 60 degrees. But, a new low pressure system that will bring some severe weather to the Central U.S. and Ohio River Valley into Monday will become blocked by the ridge. The low will weaken the ridge, allowing the low to move east. We will begin to see the first rain drops by the middle of Tuesday afternoon.
As we go through the week, this low will become quasi-stationary. An upper level high over Greenland will actually block any more systems from moving east. So, the low will rotate back into the Great Lakes. However, the cold front will remain over the east coast. New low pressure centers will form along the front and move into New England Wednesday and Thursday. The computer models are predicting we will see the heaviest rainfall on Wednesday, with embedded thunderstorms giving us an inch and a half of rain on Wednesday alone.
Due to the blocking of the upper level systems, it is still tough to predict if the models are correct after Friday. Right now, the models agree that the blocking pattern will end, allowing the cold front to move offshore. This will give us partly sunny skies by Friday afternoon. Also, if we will see sunshine, we could see high temperatures in the middle to upper 60’s. However, an upper level low to our west will bring the threat of more showers by next Saturday afternoon. Because the models have a hard time knowing when blocking patterns will end, my confidence in the forecast after Thursday night remains low.
72 hour forecast:
Tonight: Overcast with scattered showers and a possible thunderstorm. We will see a low of 40.
Sunday: Isolated showers end by 11 a.m. with partly sunny skies by the mid-afternoon. We will see a high of 54 with north winds at 8-11 mph.
Sunday night: Partly cloudy with a low of 40. Winds will come from the north-northwest at 5-8 mph.
Monday: Mostly sunny with a high of 59.
Monday night: Partly cloudy before midnight, with mostly cloudy skies afterward. We will see a low of 43.
Tuesday: Overcast skies with showers developing by the mid-afternoon. We will have a high of 53.
Tuesday night: Showers/light rain with a low of 40.
Wednesday: Showers/light rain. Highs 49-52, lows 41-44.
Thursday: Moderate to heavy rain by the early morning, with possible thunderstorms by the late morning. Highs 57-60, lows 47-50.
Friday: Showers/light rain ending by mid-morning with partly sunny skies during the afternoon. Highs 62-65, lows 46-49.
Saturday: Partly sunny with the threat of showers by the early afternoon. Highs 62-65, lows 48-51.