Philadelphia faces not one, but two days of drenching, severe thunderstorms early this week.
After being spotty over the weekend, thunderstorms will ramp up for Monday and Tuesday. That is in terms of both coverage and severity.
The strongest thunderstorms will be capable of producing damaging winds and flooding downpours. A few communities may also see hail.
Commuters will likely experience a slower ride home than to work since Monday afternoon will prove to be more active than the morning.
On Tuesday, the extent of thunderstorms that unleash damaging winds will depend on the amount of sunshine that breaks through the clouds.
Regardless of whether clouds hold firm and limit the number of severe thunderstorms, there will be plenty of moisture in the atmosphere for torrential rain to pour down and potentially flood low-lying and poor drainage areas.
Extended disruptions to travel and outdoor activities can still be expected even in communities that escape damage and flooding.
Drenching thunderstorms linger through Tuesday night before slowly pushing to the east on Wednesday.
Drier air will begin to work into the Philadelphia later Wednesday, giving way to a comfortable Thursday with low humidity and some sunshine.
Since the core of the September-like air plunging into the Midwest will lose some of its punch before reaching the I-95 corridor, Thursday's high will only be held a few degrees below the typical mid-July high of 87 F.
A blast of arctic air will be accompanied by flurries and even a localized wall of snow in some communities in the Northeast and parts of the Midwest at the start of the Valentine's Day weekend.
Spring of 2016 could rank in the top 10 warmest on record for Canada.
The coldest air of the winter will plunge southward across much of the eastern United States and will feature single-digit and sub-zero temperatures in the Northeast during Valentine's Day weekend.
A multi-vehicle accident involving cars and tractor-trailers occurred amid snowy weather and caused the shutdown of Interstate 90 in Lake County, Ohio on Wednesday afternoon.
Conditions will be favorable for lake-effect snow through the end of the week, threatening low visibility and dangerous travel conditions.
As winter weather approaches, concern for pet safety grows. Make sure you know these useful tips.
Alpine Meadows, CA (2001)
As much as 75 inches of snow over past 3 days.
Lead, SD (2005)
67 degrees, broke old record of 61 degrees set in 1983.
Greatest of all Arctic outbreaks commenced; -61 degrees in Montana.