What has changed

A high risk for rip current statement has been issued for Nantucket on Monday.

Messages

Outside a few showers/isolated t-storm risk into mid evening with the focus across the interior especially near and west of the CT River Valley. Areas of fog develop overnight which may become locally dense in spots.

Drier with a return to seasonable temperatures this week. Rain chances return Thursday/Friday.

Discussion

KEY MESSAGE 1. Outside a few showers/isolated t-storm risk into mid evening with the focus across the interior especially near and west of the CT River Valley. Areas of fog develop overnight which may become locally dense in spots.

The main cluster of showers that resulted in brief heavy rain along with a rumble or two of thunder has exited the eastern Ma coast earlier this afternoon. Behind this activity some subsidence and drier mid level air was allowing the lower clouds to begin to mix out from southwest to northeast. We will see a late rise in temperatures through early evening well into the 70s to perhaps near 80 in the CT River Valley as some peeks of sun try to develop. This will result in some modest instability developing with ML Capes approaching 1000 J/KG across parts of the interior. However. subsidence behind the earlier shortwave coupled with the main forcing well to our west will limit the additional risk. Nonetheless. a few showers and perhaps an isolated t-storm or two will be possible into mid- evening. The main focus for this activity will be across the interior and especially near and west of the CT River Valley closer to the upper level shortwave.

Otherwise. the main story later tonight will be for the development of fog some of which may become locally dense. Winds become light/calm overnight coupled with partial clearing, wet ground and dewpoints remaining in the 60s will set the stage for fog development. Some of the fog may become locally dense too. Low temperatures overnight will drop into the middle to upper 50s in the outlying locations. to the middle 60s in the urban heat islands of downtown Boston/Providence.

KEY MESSAGE 2. Drier with a return to seasonable temperatures this week. Rain chances return Thursday/Friday.

A post-frontal air mass ushers in drier conditions and warmer temperatures on westerly winds this week. As skies gradually clear from the dreary weekend, dewpoints will begin to drop slightly. into the upper 50s as opposed to the low to mid 60s we've been seeing. High pressure begins to slowly build Tuesday into Wednesday, prolonging the clear skies, drier weather, and warmer temperatures through the middle of the week. Expecting temperatures to return to seasonable, in the upper 70s to low 80s, and feel less humid thanks to the lower dewpoints through the end of the week.

Chances for rain showers return Thursday and Friday as a low pressure system develops over the Great Lakes and meanders east through southern Ontario. Some uncertainty remains regarding the onset of the showers as there's little consistency in the global ensembles on the actual placement of the low as it tracks through Canada; however, confidence has ticked up slightly in a later show of showers Thursday evening into the overnight period compared to yesterday's model runs.