Listen to article \u2022\u00a00:00 min<\/p>\n
Given the atmosphere\u2019s impatience, it would be understandable if some folks believe that the summer of 2026 began weeks ago.<\/p>\n
But officially, the astronomical summer does not start until 4:24 a.m. Sunday, the instant of the solstice, when the sun beams its most direct light on the Tropic of Cancer. (That\u2019s the one that bisects Mexico.)<\/p>\n
Perhaps the pleasant temperatures this weekend are an overdue solstice gift to the region.<\/p>\n
Officially, on 14 days this year, the temperature has reached at least 90 degrees <\/a>at Philadelphia International Airport<\/a>. While not a record \u2014 this happened 21 times before the 1991 summer solstice \u2014 that is a total more appropriate to midsummer. The annual average is about 30, and usually this kind of heat doesn\u2019t get a jump start in mid-April.<\/p>\n Is it going to get hot again?<\/p>\n Are polar bears white?<\/p>\n At least three veteran seasonal forecasters have commented that they expect the burgeoning El Ni\u00f1o event <\/a>to work against punitive hot spells in the region. <\/p>\n During El Ni\u00f1o, sea-surface temperatures remain above normal in the tropical Pacific for several months, agitating the overlying air and affecting weather across the globe. This one may be among the strongest and is forecast to mature during the summer, earlier than usual. <\/p>\n During six early-developing strong El Ni\u00f1os, summer temperatures in Philadelphia were near or below average. <\/p>\n However, the scientists at the government\u2019s Climate Prediction Center evidently are not buying it. In both the July and the July 1-through Aug. 31 outlooks posted Thursday, they saw the odds favoring above-normal temperatures.<\/p>\n On average Philly has a combined 20 days of 90-degree highs in July, when the Earth is the farthest it gets from the sun, and August. (Along with a September bonus of two more.) <\/p>\n How come it\u2019s warmer, if we\u2019re farther from the sun?<\/p>\n On average the Earth is about 93 million miles from the sun, but since its orbit is an imperfect circle the distance varies by roughly 3 million miles.<\/p>\n At 1 p.m. on July 6 our planet will be 94.5 million miles from the sun, by EarthSky\u2019s calculation, its farthest distance of the year. It makes its annual closest approach in January, which is why winter in the Northern Hemisphere is the shortest season; the gravitational bump speeds up the trip, and February gets shortened. <\/p>\n The seasonal weather rhythms are about the Earth\u2019s axial tilt, not distance from the sun, and the planet takes its time responding to the changes in solar energy. Just as January is colder than December on average, July is more than 5 degrees warmer in Philly than June on average. Just how warm it gets the rest of this summer may have a lot to do with how much drier it gets.<\/p>\n Will the drought conditions ever end?<\/p>\n They always have, but this has been quite an extraordinary run, even if the plant life has managed to avoid major distress.<\/p>\n The entire region, save for extreme northeastern Bucks County<\/a>, is in a state of \u201csevere drought,\u201d according to the U.S. Drought Monitor<\/a>, with Cape May<\/a> County in \u201cextreme drought.\u201d<\/p>\n The promised rain to start the workweek should help, but Philadelphia has experienced 10 consecutive months of below-normal precipitation, a rarity in an area in such proximity to bodies of water that are sources of rainfall. All of New Jersey and Chester County<\/a> remain under drought emergencies.<\/p>\n Dryness can promote heating, since the sun does not have to divert energy evaporating water.<\/p>\n However, unusual coolness also can accompany dryness, said Sarah Johnson, warning coordination meteorologist at the National Weather Service office in Mount Holly. Having lived in North Dakota for 20 years, she knows her dry air. <\/p>\n A lack of moisture can be a boon for cooler nights. Water vapor in the air inhibits nighttime cooling by blocking heat from escaping into the atmosphere.<\/p>\n It also happens that less vapor in the air is ideal for sky-watching, and that could come in handy in August. <\/p>\n This could be a big year for the Perseids<\/p>\n Last year, you may recall that the moon showed its big face during the peak of the annual Perseid meteor showers, the most popular of the year.<\/p>\n This time around, the moon is getting out of the way, and will be in its \u201cnew\u201d phase during the peak early mornings of Aug. 12 and 13.<\/p>\n While the Geminids, which occur in December, are considered the most prolific showers of the year, according to the American Meteor Society, they are not as popular as the Perseids: People tend to prefer August nights to December\u2019s. <\/p>\n The Perseids are so named because the cometic detritus that is ignited by the atmosphere appears to radiate from the constellation Perseus. In the early-morning hours, that typically is low in the northern sky. <\/p>\n Under ideal conditions \u2014 ultra-dark, light-pollution free skies \u2014 as many as 90 meteors an hour might be visible, EarthSky says. <\/p>\n But the moon will be the star in late August<\/p>\n