12:20 PM | *Powerful storm to bring heavy rain, strong winds and possible severe thunderstorms late tomorrow/tomorrow night*
Today begins a stretch of unsettled weather that will continue into early Thursday as two low pressure systems impact the Mid-Atlantic region. The first surface low pressure system is rather weak and it will continue to generate generally light-to-moderate rainfall for the area before dissipating later tonight. A second and much more powerful storm will pull out of the Gulf of Mexico region on Wednesday and it’ll take an inland track through the Ohio Valley. This second storm will impact the Mid-Atlantic region with heavy rainfall, strong winds and possible thunderstorms from later tomorrow through much of tomorrow night. In fact, the thunderstorms may reach severe levels later tomorrow/tomorrow night in portions of the southern Mid-Atlantic region extending from DC to the Delmarva Peninsula to southern New Jersey and perhaps even as far north as southeastern PA.
An unusually strong storm for February will move rapidly northward on Wednesday likely reaching western New York state by tomorrow night. This storm will have a big impact on the DC-to-Philly-to-New York City corridor with heavy rain, strong winds and possible thunderstorms from later tomorrow through much of tomorrow night. The storm could intensify enough on Wednesday to the point where it reaches some of the lowest pressure levels ever seen during the month of February in parts of the country east of the Mississippi River.
Given the expected deepening pressure gradient later tomorrow/tomorrow night, winds will intensify and could gust to 50 mph or so in the I-95 corridor. Temperatures will start off on the cool side tomorrow morning, but could jump 10 degrees or more in an hour’s time late tomorrow following the passage of a warm frontal system. Thunderstorms will break out on the warm side of this storm later tomorrow and could actually reach severe levels as far north as the southern portion of the Mid-Atlantic region extending from DC to the Delmarva Peninsula to southern New Jersey - perhaps even as far north as southeastern PA. In fact, impressive deep wind shear profiles in the southern Mid-Atlantic region late tomorrow will enhance chances for severe weather including damaging winds and isolated tornadoes.
Flooding may also become a problem in areas to the northeast of the PA/MD border by later tomorrow night as rainfall amounts could exceed two inches when including today’s rainfall with the upcoming second storm. Snow will be confined to the northwest flank of this storm in places like Illinois, Indiana and Michigan where up to a foot of snow can accumulate by Thursday morning. A cold front will clear the Mid-Atlantic region early Thursday and this will pave the way for much colder air to return on Thursday night and Friday along with the threat for snow showers.
Meteorologist Paul Dorian