Why did parts of the Lehigh Valley get severe weather Saturday? Storms had ‘no real organization,’ meteorologist explains

The disorganized nature of the storms that hit Saturday led to some areas of the Lehigh Valley, Southeastern Pennsylvania and New Jersey experiencing more severe weather than others, according to the National Weather Service.
“There was no real organization to the storms, such as a front or a boundary they were confined to,” said Matt Burdy, a meteorologist with the NWS office in Mount Holly, New Jersey. “They were very scattered and storms just popped up throughout the afternoon.”
On Saturday, the Lehigh Valley was under a flash flood warning and a thunderstorm warning that cautioned against the possibility of quarter-sized hail.
A couple of major roads flooded Saturday, including the eastbound lane of Interstate 78 near the Route 309 exit. Flooding also briefly closed Route 378 between Colesville Road and Mountain Drive in Lower Saucon Township. Burdy said the NWS received some reports of flooding near creeks and other bodies of water, but it primarily occurred in areas where water could accumulate quickly and drain slowly.
“In the more urbanized areas, there’s a lot of asphalt and concrete, not dirt, grassroots or sand like we have in New Jersey,” Burdy said. “There’s just not enough area for water to drain fast enough.”
Videos shared on social media from around the region showed hail falling in many areas. Burdy said the weather station also received many reports of large hail — same came from the Allentown area but many were from the Philadelphia and southern New Jersey areas.
Burdy said the instability and the lack of organization in the storms were conducive toward formation of hail, but there was not enough wind shear tilting the updraft, which would have allowed larger hailstones to form that could have caused serious damage.
Burdy said it is unlikely the Lehigh Valley will see any more storms like Saturday’s for a while. Rain is possible Sunday night and Monday morning but nothing significant is expected in the Lehigh Valley until next weekend, he said.
“Probably during the Friday and Saturday timeframe. There’s still a little disagreement of the exact timing but it looks like the start of the weekend is probably going to be a little wet,” Burdy said.
Here is the extended forecast from the National Weather Service for the Lehigh Valley:
Sunday night: Showers and thunderstorms are likely, with showers and possibly a thunderstorm after 3 a.m. The chance of precipitation is 80% with new rainfall not to exceed a tenth of an inch unless thunderstorms occur. Patchy fog is expected between midnight and 1 a.m. Temperatures will hit a low of around 55 degrees. Wind will blow east around 10 mph.
Monday: Showers are likely, mainly before 10 a.m. It will be cloudy through mid-morning but will gradually clear. The high temperature is expected to be near 66 degrees. Southwest wind will blow at speeds of 10-15 mph. The chance of precipitation is 60%, with new precipitation amounts of less than a tenth of an inch possible.
Monday night: It will be partly cloudy, with a low of around 44 degrees. Wind will blow west at speeds of 10-15 mph.
Tuesday: The day will be partly sunny, with a high temperature near 56 degrees. It will be breezy, with a west wind of 15-20 mph.
Tuesday night: It will be partly cloudy, with a low temperature of around 38 degrees.
Wednesday: Sunny, with a high near 65 degrees.
Wednesday night: Partly cloudy, with a low of around 44 degrees.
Thursday: Mostly sunny, with a high near 78 degrees.
Source: Morningcall