Here Comes a Soaking!
Overrunning rain is beginning to break out well ahead of the surface and upper level lows. Lower levels of the atmosphere are very dry right now but will steadily moisten up so eventhough the radar looks very impressive the rain will be pretty light...for now. By tomorrow morning the heavier rain will be falling with good diffluence aloft and the core of the low level jet escorting in the moisture, rain will be heavy at times. This will be a cold windswept rain, especially near the coast where gusts will exceed 30 mph and temps will hold steady in the low to mid 40s...pretty miserable if you ask me. By afternoon the steady rain will be tapering but we won't be through...the upper level low will pass overhead in the evening so additional showery type rain is expected and thunderstorms are still possible with the lifted index getting down close to zero. The storm departs tomorrow night but cyclonic flow will keep low clouds and fog around for the majority of the night. Winds will back to the NW on Thursday bringing in drier air and therefore increasing sunshine. The sun will be out in full force on Friday but a surface front will have slipped through...this means a chilly NE wind will prevail and temps will struggle into the 50s. The weekend is still looking pretty iffy with another round of potentially soaking rain Saturday night through at least half of Sunday...I remain hopeful that the second half of Sunday will be salvaged with some partial clearing. Good news...Patriots Day still appears dry and with now seabreeze expected at this time, the runners will have the wind at their backs!