There Is A Very Significant Flood Potential On Sunday Across Western & Central Mass

For The Rest Of This Afternoon: A mixture of sunshine and clouds is expected throughout the rest of this afternoon with very warm and humid conditions. In addition, some scattered thunderstorms will be a possible with most of this activity occurring over the Berkshires, the Hilltowns of Western Mass and across the Worcester Hills, especially west of I-190. Temperatures the rest of this afternoon will be near 85 Degrees. Winds will be South at 5 to 10 mph. Late Tonight Through Sunday: I am very concerned that we are looking at a very significant flood event during Sunday across the entire area due to extremely heavy downpours that’ll produce very high rainfall rates. Also, I have some concerns that a few of the thunderstorms may be on the strong to severe side with gusty winds and a couple of tornadoes possible. A frontal boundary is expected to stall over the region by late tonight and during the day on Sunday. This front will interact with a very humid air mass that’ll really be able to wring out the rain from heavy showers and thunderstorms. To make things even worse is that this front will hang over our area for about 18 to 24 hours, which means that there will be a prolonged period of on and off heavy showers and thunderstorms that begin late tonight and continue through the day on Sunday. Current guidance indicates that it’ll only take 1.50 to 2.50 inches of rain in one hour to produce widespread flash flooding across the region. Given that these heavy downpours will be able to easily produce 1 to 3 inches of rain in one hour, I think that flash flood threat across the entire region is extremely high. If that wasn’t enough, there is also the possibility that a few of the thunderstorms could be on the strong to severe side. Very gusty winds look to be the main threat which could lead to isolated tree damage and isolated power outages due to trees easily being pushed over due to the extremely wet ground conditions. Also, a couple of tornadoes are possible are possible as the very humid air mass interacts with moderate amounts of low-level wind shear. To summarize things a little more – Heavy showers with scattered thunderstorms are expected to overspread the entire area around dawn Sunday morning. Widespread heavy showers with scattered thunderstorms are then expected to continue throughout the day on Sunday. The worst part of the heavy showers and thunderstorms look to occur from about 9-10 am until about 3 pm Sunday when extremely heavy downpours will be producing 1 to 3 inches of rain per hour leading to localized flash flooding of streets, highways, underpasses, urban areas and areas of poor drainage.. In addition, a few strong to severe thunderstorms are possible during this time frame, which could produce gusty winds and perhaps a couple of tornadoes. The shower and thunderstorm activity should gradually diminish and end during Sunday evening. All-in-all, Sunday looks like an extremely active day in terms of weather and you should keep checking back for updates. Given the expected flooding, my recommendation is to perhaps cancel or reschedule any plans you may have. If you are planning to be on the roads on Sunday, you may want to reconsider as extremely heavy rainfall rates will lead to flooded roads and extremely poor visibility.