After two of Philly’s warmest months on record, forecasters expect an August encore
The June 1-July 31 period has been one of the warmest on record, and August is due to start with triple-digit heat indexes.
Another “heat advisory” is in effect for Thursday and Friday for the Philly region, and after two months of this, that tiresome cautionary flag may be about as popular as “road work ahead.”
High temperatures for the first two days of August are due to crest in the mid-90s, with triple-digit heat indexes, said Patrick O’Hara, meteorologist with the National Weather Service Office in Mount Holly.
Unfortunately for those who are about ready to move on from sultriness and humming air-conditioning motors, forecasters are saying that the rest of the week might be indicative of the rest of the month, although the region may get at least a few breaks.
The government’s Climate Prediction Center’s updated August outlook has chances strongly favoring above-normal temperatures in the Philadelphia region and in much of the nation, based on analyses of various computer models; soil moisture; recent precipitation patterns; and, of course, longer-term climate trends.
And around here, that would be very much in keeping with the summer of 2024 trends.
With a preliminary average temperature of 81 degrees, July 2024 would rank among the five warmest Julys on records in Philadelphia, based on data dating to 1872.
The first two months of the meteorological summer that began June 1 would constitute the warmest such period in 30 years.
One of the dominant features of the summer has been a high-pressure area centered in the North Atlantic, a so-called Bermuda high, said Paul Pastelok, veteran long-range forecaster for AccuWeather Inc. Winds circulate clockwise around highs, so areas to the west of the center experience warming winds from the south.
Pastelok noted that so far this season, Philly has recorded a temperature of 90 degrees or higher on 24 days — the same as all of last year. The long-term average for the entire season is 30 days.
Rainfall has been capricious, and precipitation in Philadelphia and its four neighboring Pennsylvania counties has been significantly below normal, particularly in the city and in Bucks and Montgomery Counties.
Dry conditions are more favorable for heating: Wet ground and foliage diverts some of the sun’s heating energy to evaporation.
The outlooks
While the climate center sees an overall warm month, it also suggests that the region will get a break the second week in August, with models favoring above-normal rainfall in much of the nation.
Some showers are likely Friday and Saturday, but Pastelok said that “an important front” may be a significant rain-maker the following weekend. If the front stalls, he said, “there could be just constant showers and thunderstorms Saturday.”
He added that another cool-down is possible around the 20th.
But like the climate center meteorologists, he believes August will end up bookending yet another hot summer in Philly.