The Mother's Day nor'easter is on track and we're getting more confident in some of the specifics. Yesterday on this blog I posed a couple of questions of things we still didn't know the answers to and now we can start answering them with some confidence.
The first issue was how early will the rain begin on Saturday? We're thinking 10 a.m. to 2 p.m. for a start time across the state - and many areas on the I-91 corridor and points east will be dry until at least noon or 1 p.m. If you have stuff you need to do outside there should be a window Saturday morning where things are dry. If we're lucky we may be able to push the start off by a couple hours still!
As for rainfall totals our 1"-2" forecast still looks good - but I do think some areas could pick up 3"+ of rain. Localized bands of heavier precipitation are a good bet. One thing that jumps out at me is the "M-Climate" or "model climate" off the GFS being maxed out. Basically, the GFS model is re-run for the last 30 years and compared to the current forecast to computer M-Climate. The amount of rain being produced in a 12-hour period Saturday night on the most recent GFS run is greater than any of those 30-years of reforecasts for this time of year! That's a good signal for locally heavy rain and possibly flooding.
As for Sunday - the forecast is still a tough one. The heavy rain will end around daybreak and we should see some light rain lingering during the morning. I do think there will be a bit of a break late morning/midday - the sun may even come out! That said, showers will likely redevelop during the afternoon as a powerful upper level disturbance swings through southern New England.