Severe storms Monday in Philadelphia region could bring tornadoes, damaging winds, heavy rain. Here's the forecast.
A strong cold front will move through Monday into the night, bringing the potential for strong to severe thunderstorms across the region.
The main concern is damaging wind, but a few brief tornadoes and pockets of heavy rain that could cause localized flash flooding are also possible. Even outside of storms, it will be windy with gusts around 35 to 45 mph, especially closer to the coast, where wind gusts could approach 50 mph.
Ahead of the main line of storms later this evening, there could also be a few rounds of storms early this afternoon that will come with a threat for severe weather. That said, the greatest risk for damaging winds and tornadoes will be between 4 and 11 p.m. as the storm threat moves out overnight.
NEXT big weather changes
On Monday, gusty south winds push temperatures to the upper 60s and low 70s. It will be mostly cloudy with scattered showers and isolated rumbles in the morning.
Late Monday afternoon, an extremely strong cold front approaches and triggers pockets of heavy rain and severe storms during the evening.
Significant threats include damaging straight-line winds at 50-70 mph, heavy rain with localized flooding, and tornadoes.
WHERE: The entire Delaware Valley is under a threat of severe weather, but areas west of Philadelphia that see storms earlier have a better shot of the worst severe weather.
TIMING: Rounds of storms after 2 p.m. today could produce severe weather, but the greatest severe risk is 4-11 p.m. ahead of a strong cold front.
WHAT:
- Level 3 of 5 severe risk for Philadelphia and the surrounding areas – for us, this is rare
- Level 2 of 5 near the Jersey Shore
- Level 4 of 5 just west of the DMA – rare to see this level so close
THREATS:
- 50-70 mph straight-line winds
- Tornadoes possible. We have an elevated level of spin/shear with marginal instability – combined, tornadoes are certainly possible
- Heavy rain with flash flooding. 1-2" rain possible with higher amounts under any storms
- High winds (non-severe) from the south, gusting 35-45 mph (up to 50 mph near Shore) ahead of the cold front
IMPACTS:
- Travel delays and cancellations in the afternoon and evening
- Outdoor activities and sports canceled in the evening
- Scattered power outages
- Wet or locally flooded roadways
- Trees down, possible damage to structures
Behind the front, another blast of cold spreads across the region with a wintry mix and wet snow late Monday night.
Tuesday weather alert
A big temperature drop follows on Tuesday, aka St. Patrick's Day. It'll be a bitter cold start with lows near or slightly below freezing and wind chills in the mid-low 20s Tuesday morning.
Highs Tuesday afternoon will struggle to climb into the low 40s.
Here's your 7-day forecast:
Monday: NEXT Weather Alert for Storms. High 67, low 47.
Tuesday: NEXT Weather Alert for cold. High 42, low 32.
Wednesday: Partly cloudy. High 41, low 25.
Thursday: Partly cloudy. High 51, low 30.
Friday: Mostly sunny. High 57, low 37.
Saturday: Clouds, some sun. High 55, low 40.
Sunday: Maybe a shower? High 50, low 35.