Thunderstorms could put a damper on fireworks displays across the Valley and much of Pennsylvania tonight.
Meteorologists are calling for typical July weather patterns over the long holiday weekend. Following a warm and humid day today, AccuWeather meteorologists say there is a 50/50 chance of thunderstorms during prime viewing hours.
Dan Pydynowski, AccuWeather meteorologist, said today will be warm and humid with temperatures in the mid-80s. "There is a chance of scattered thunderstorms at night," he said. "When you’re out watching fireworks, it will still be warm and muggy, low 70s with not much of a drop-off."
Forecasts have the high temperatures hitting 88 today, with the humidity pushing the heat index to 98. On Friday, the high will reach 85 with a heat index jumping to 95.
AccuWeather reports some of the strongest storms are likely to erupt from central Pennsylvania during the afternoon hours today. "These storms will then crawl eastward during the evening, We expect storms to stay south and west of New York City during Thursday evening fireworks," AccuWeather Senior Meteorologist Dave Dombek said. Most of the storms will occur between 3 p.m. and 9 p.m. and may only last about an hour.
Even if the Valley dodges rain during the fireworks, the heat and humidity could have an impact on how the fireworks appear.
The National Weather Service in State College says higher humidity leads to less vibrant colors from the fireworks. Also temperature inversions — where the temperature increase with an increase in height — can trap smoke on the surface, leading to reduced visibility and poor air quality.
Pydynowski said Friday and Saturday will be a lot like Thursday with thunderstorms possible in the afternoon across the region.
"There will be a greater chance of thunderstorms throughout the day," he said. "The best time for thunderstorms will be the afternoon. There will be some relief on Sunday. Showers are possible, but it will be less humid with highs in the low 80s."