Summer 2022 in Philly is about to set more records

With the heat and dryness having browned the grasses around here to “shredded wheat” and induced trees to drop their leaves prematurely, Philadelphia is about to add more records to its summer weather resumé.

Based on preliminary data, the average official high temperature at Philadelphia International Airport for the June 1-to-Aug. 31 period, 88.1 degrees, would set a record for a meteorological summer in the 152 years that the government has been keeping track.

In addition, the average temperature for the last two months, 81.7 degrees, would be higher than any other July and August, according to an Inquirer analysis. The National Weather Service is expected to issue its official tallies in the next few days.

This may seem like a Philadelphia summer tradition about now.

» READ MORE: The summer of 2020 was the No. 3 hottest in Philly

Philadelphia, like the planet, has experienced a warming trend that has been picking up speed during the last 30 years.

The National Oceanic and Atmospheric Administration estimates that global temperatures are increasing at the rate of 0.3 degrees Fahrenheit per decade, more than double the rate of previous decades. In addition, after sunset, local warming appears to be getting a kick from more water vapor in the air, said Bob Larson, expert senior meteorologist at AccuWeather Inc.

That has been a “big factor” in rising nighttime temperatures across the country, he said. Warmer air can hold more moisture, which inhibits daytime heat from radiating into space. Philly fell just short of the summer record for high overnight minimum temperatures.

» READ MORE: Yes, this summer warmth is very much a trend

Conversely, quite a significant dry run that began last month evidently has given the daytime readings a lift. The high temperatures averaged just over 90 in July and August.

Summer rains are notoriously capricious, and parts of the region, notably Chester County, haven’t been as parched as areas to the east that could use a serious soaking about now. New Jersey and part of Pennsylvania, including Philadelphia and most of its suburbs, are under a “drought watch.”

“It’s been very dry on the I-95 corridor from Philadelphia to Boston,” said Larson. August rainfall in Philly, New York, and Boston has been about a third of normal, according to the National Weather Service.

» READ MORE: Pennsylvania declares drought watch for Philly and surrounding counties, asks residents to conserve water

The dried and cracking soils have been ideal for daytime heating since the sun has had to spend less energy evaporating water.

After a gentle June, in which Philly’s rainfall was well above average and temperatures were right about where they should have been, nature turned off the spigots and turned up the heat in the urban corridor.

Those were ideal conditions for turning grass to “shredded wheat,” said Larson. At least the mowers got a break.

Given that the areas along the I-95 corridor are so close to bodies of water, however, the nights tend to be humid, and thus sultry and all the more reluctant to cool.

» READ MORE: A drought watch is in effect in Jersey

So far the city has recorded eight heat-related deaths, said Matthew Rankin, spokesperson for the Department of Public Health.

That also would be a continuation of a trend — a generally benign one.

In the last 10 years, 42 heat-related deaths have been reported in the city, compared with 10 times that number in the 10-year period that ended in 2002.

» READ MORE: Summers are hotter, but heat-wave deaths are declining

Both NOAA and the CDC have praised Philadelphia for its efforts to draw attention to heat hazards in the deadly 1990s and responding aggressively to heat emergencies.

The declines might also be related to the fact that the city has avoided the lengthy, punitive heat waves of the 1990s. In 1995, the temperature reached 90 or better 17 consecutive days at one point. The longest such heat wave this summer was 10 days.

Only one high-temperature record, of 99 degrees was set, 99 degrees on July 24.

If you enjoyed the weather around here Wednesday and Thursday, stick around Friday. It will be dry and beautiful with a high in the 80s and a refreshingly cool night with lows in the mid-60s.

But readings are due to creep back to 90 on the weekend, with hit-and-miss showers possible Sunday, Monday, and Tuesday.

As per usual approaching autumn, fronts will be crossing the region in the coming days, but Larson says nothing suggests any coolness will last.