The storms could bring damaging winds, hail and flash flooding, the National Weather Service says. The next chance for severe weather will be Friday, according to the weather service.
Severe thunderstorms with damaging winds 70 miles per hour or greater and large hail exceeding 1 inch in diameter are possible during the afternoon and evening, the National Weather Service says.
The trigger is an approaching cold front from the west.
There will likely be some strong and possibly severe thunderstorms JUST to our west on Monday and Monday evening. We are under a slight risk for severe storms through Monday morning. Also, in looking at some of the tornado-related parameters (level of saturation, low level turning of wind, among others), the tornado threat will not be absolute zero. The second graphic shows a weather measurement known as precipitable water.
Over two inches of rain are forecast for the western part of the state, compared to under an inch in the greater Boston area. That is a very high number for this parameter and is a reflection of the high water content of the atmosphere which is adding to the general stickiness.
Flash flood watch in effect until 9 p.m. Monday.
Severe thunderstorms possible Monday
A flash flood watch has been issued for Adams, Lancaster, Lebanon, and York Counties for this afternoon and evening. In addition to road closures, several reports of landslides have also been received due to the daily heavy rain.
The potential for severe weather should wrap up by Tuesday. To put it bluntly the late day commute could be nightmarish with flooded or blocked roadways and power outages.
Thursday: Partly to mostly sunny, still comfy.
The main ingredient to Monday's forecast is the sunshine breaking through the clouds late this morning and early this afternoon.
He said there was a chance of hail if a severe storm develops, but the worst weather could be just to the northwest of Long Island. You should have a way to monitor the weather and warnings as they are issued.