We are tracking a Mesoscale Convective System, that will develop across the Great Lakes region Tomorrow, slides its way Eastward into the state of Pennsylvania by Thursday Morning.

The MCS will reach Western PA by Thursday Morning…likely right around the morning rush hour, before pushing East from there and reaching Eastern PA by the Afternoon hours.

Unlike typical thunderstorms, with a Mesoscale Convective System, on radar you will see a large area of heavy rain and thunderstorms. These will not be hit or miss type storms. More than likely your backyard will see some rainfall Thursday. Just how much rainfall is the question.

The STORM PREDICTION CENTER has stated in their forecast the MAIN THREATS for Thursday involve damaging winds and hail. As it stands right now the further South you go in PA, the better chance to see Severe Weather activity. We will have to watch for future trends to see if the threat for an isolated tornado increases, but the threat is very low currently.

Area A – The STORM PREDICTION CENTER has placed this region under a SLIGHT RISK for Severe Weather. Main threats: Damaging winds and hail.

Area B – The STORM PREDICTION CENTER has placed this region under a MARGINAL RISK for Severe Weather. Although the threat is lower than those in Area A, the main threats will still feature damaging winds and hail.

Area C – This area will just see plain old thunderstorms with some heavy rain. No real severe threat in this region.

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So how much rainfall are we talking? Potentially enough for flash flooding in areas throughout PA.

Area A – Highest risk for flooding rains. Most of the rainfall will fall in a 6 hour period. Early estimates show anywhere between 1 and 3 inches of rainfall.

Area B – Moderate risk for flooding rains. Early estimates show up to 2 inches of rain in a 6 hour period.

Area C – Low risk for flooding rains. Most guidance shows less than an inch of rainfall for this region.

*Please note, if your backyard gets hit by a severe storm, there is the chance for these numbers to double in very localized cases.

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Josh has been passionate about weather as long as his memory dates! From watching the Weather Channel at age 7, to making hand-drawn hurricane maps at age 11, starting his first weather site at 13, and founding PWA at 15 and forecasting for the state for the past 9 years, Josh's interest in weather has never dwindled! As difficult as it is, he greatly enjoys forecasting for Pennsylvania due to its countless microclimates. The state is an East Coast severe weather hotspot and nearly always home to the rain/snow line during winter storms!