With less than 12 hours to go in the month of May, the skies have opened up and heavy rain is falling across much of the region. This will likely put enough rain in the books to knock us out of the top 10 driest Mays in record. It’s ironic, years from now, unless you look at the daily data for this month, you won’t realize just how dry it was.
The good news is the rain has arrived and in some cases it’s falling very hard. I suspect 1 to 3 inches of rain to fall between now and Tuesday evening when the bulk of the rain will have occurred.
There are flash flood watches and even some warnings as I write this. Flash flood warnings tend to be very short in duration lasting as little as an hour and up to several, so check the latest advisories or my Twitter feed @growingwisdom for what is the current warning status. The map below is as of 4:25 PM.
Flash flooding tends to mean roads become impassible and if you aren’t 100% sure how deep a puddle is, turn around. You don’t want to be THAT person on the news who’s standing on top of their car waiting to be rescued.
There will be periods of rain through Tuesday morning with times when the rain isn’t falling much at all. Temperatures have rapidly cooled as the winds turned onshore and are now coming from the northeast. The next three days will be unlike anything we have seen since the very early days of May. Highs won’t reach 60 degrees in most spots and with overnight lows in the 40s, dare I say the heat might be needed by Tuesday or Wednesday morning.
One of the heavier periods of rain is likely to come overnight Monday night when a wave of low pressure passes near southern New England enhancing the rainfall.
The map below form the GFS model predicts most areas to see over 2 inches of rain. These predictions, just like in winter, have a margin of significant margin of error. This is why I am saying 1 to 3 inches of water.
Wednesday will be a nicer day with dry and warmer conditions. Highs range from 65-70 and with all the water in the ground you’ll notice the lawns greening up again and many of the plants will respond nicely.
It continues seasonably warm Thursday and Friday with a chance of showers sometime later in the weekend, but this is very tentative and my confidence in the 7th day of a 7 day forecast isn’t very high.
Have a great evening.