Storms, heavy rain to hit Philadelphia region today with brief tornado risk before Friday chill

A storm system moving through the Philadelphia region will bring several rounds of wet weather today and into Friday, with the greatest potential for thunderstorms from midmorning through the early afternoon.

Showers and embedded storms will become more widespread between about 11 a.m. and 2 p.m., with locally heavy downpours, gusty winds and reduced visibility creating potentially difficult travel conditions. Ponding on roads is possible, particularly where heavier rain falls over the same areas.

While widespread severe weather is unlikely, we are in a marginal (level 1) severe risk and a 2% tornado risk due to the warm front moving through and the wind shear accompanying today's storms — a brief spin-up tornado can't be ruled out.

Rain will become more scattered later this afternoon, but the unsettled weather won't be finished. Additional showers are expected tonight, followed by another round of steadier rain Friday morning.

Colder air arriving behind the system will send temperatures tumbling from near 60 degrees today into the 40s Friday, with a brisk breeze making it feel even chillier. In the Poconos, some slushy accumulation is possible Friday morning, with flakes mixing with rain even into the Lehigh Valley.

Rain should gradually taper Friday afternoon, setting the stage for a mainly dry but cool weekend.

TODAY: Mostly cloudy with rounds of showers and thunderstorms, especially late morning through early afternoon. A few storms could bring gusty winds and heavy rain before activity becomes more scattered later in the day. Mild, with highs in the upper 50s to lower 60s.

TONIGHT: Mostly cloudy with additional periods of rain, especially later tonight. Turning cooler with lows in the lower to mid-40s.

FRIDAY: A chilly, breezy and unsettled day with periods of rain during the morning and a few lingering showers possible in the afternoon. Temperatures will struggle to climb, with highs mainly in the lower to mid-40s. A significant change from Thursday's milder weather.

PLANNING: The weekend looks considerably quieter, although clouds will be stubborn on Saturday with a brisk breeze and highs in the upper 40s. Sunday brings some morning sunshine before clouds increase, with temperatures recovering into the lower 50s. The dry weather continues into early next week, with partly sunny skies Monday and Tuesday and highs gradually climbing through the 50s.

NEXT BIG CHANGE: After today's stormy weather and Friday's chilly rain, a stretch of drier and more seasonable weather takes hold this weekend and continues through much of next week. Sunshine becomes more plentiful by midweek, with temperatures gradually rebounding into the mid- to-upper 50s.