Judging by the early leaf fall, it’s safe to assume that the trees have joined the seasonal movement for pumpkin spice and orange-and-black Halloween colors.

The astronomical drop in temperature, when the sun shines directly on the equator, does not occur until Sunday at 8:44 a.m.

But in an incredibly dry period, the trees have not only littered lawns with their brittle cinnamon leaves, they have also left clues about the course of this year’s leaf color – nature’s annual compensation for the loss of more than 2.5 hours of sunlight between September 1 and Halloween.

How the foliage will evolve is one of the cosmic questions that preoccupies us as the direct light of the sun begins to sink ponderously southward.

What about the falling leaves and what can leaf-gazers expect?

According to foliage experts, leaf color may be early in the Northeast, and that’s because of this dry spell. Officially, Philadelphia has only received 0.36 inches of rain this month, and that’s more than Bridgeport, Connecticut, or Bangor, Maine.

Jim Salge, a New Hampshire meteorologist and veteran foliage forecaster for Yankee magazine, said he expects an earlier-than-usual color change and a short season, at least in northern New England.

Pennsylvania’s dry conditions and cool nights earlier in the month “could speed up the coloring process,” said Ryan Reed of the state Forest Service, who writes the state’s weekly foliage reports, and could shorten the season.

But Salge and Reed agree that leaf-gazers in the best viewing areas in the Northeast can expect a very special bouquet of foliage. Reed said, “Drought conditions can actually increase the vibrancy of the colors, as long as the leaves don’t dry out too much.”

Will it ever rain again in the Philadelphia region and the rest of the Northeast?

NO While rains are on the way to ending the deficit, showers are possible Tuesday night through Thursday, and there’s a good chance for above-average precipitation next week, according to NOAA’s Climate Prediction Center.

Rainless Septembers are not uncommon here. In 2005, for example, Philadelphia recorded just 0.21 inches of rain. The normal total for this month is 4.4 inches.

Historically, however, September has been one of the wettest months of the year, largely due to the remnants of tropical storms that accumulated over 25 centimeters of rainfall in 1999 and 2011.

What happened to the expected tropical storms?

Some of the best minds in meteorology have asked themselves the same question.

Meteorologists had confidently warned that this could be a record-breaking Atlantic tropical storm season, with ultrawarm waters in the hurricane basin. However, only seven named storms have formed so far, three fewer than normal at this point in the season.

While this hasn’t been the year for holdovers in the Philadelphia region, keep in mind that the season doesn’t end until November 30th.

When will the first frost occur in the Philadelphia region?

It is well known that growing seasons are getting longer and the official first frost – when the temperature drops to 0 degrees – is coming later. In Philadelphia, it has already arrived on average in the first week of November.

But predicting the first frost is more problematic because it depends heavily on terrain features, and frost can occur at temperatures above freezing, about 36 degrees, says Lee Robertson, a meteorologist with the National Weather Service office in Mount Holly. Surfaces on which frost forms can be cooler than the air – think of car roofs.

Unless you live downtown or right on the Delaware, you can expect the temperature to drop to 36 degrees sooner than in the tropics around Philadelphia International Airport, where the records are stored.

Officially, the first temperatures of 36 degrees were recorded in Philadelphia on September 25, 1963, and from October 8 onwards, lows of 36 degrees or less were recorded at least once every day.

When can we expect the first snowfall in Philadelphia?

The first measurable snowfall in Philadelphia is, on average, November 21. Usually, just over 2 inches of snow has officially fallen before the winter solstice. The first snowfall, 2.2 inches, fell on October 10, 1979.

And the latest news? In the winter of 1972/73, this did not happen at all.

You can expect a flurry of winter forecasts over the next few weeks, but hurricane season suggests a certain inadequacy in long-range weather forecasting. Don’t believe anything until you see the white flakes.

Will the Philadelphia area see the Northern Lights this fall?

Predicting the behavior of the chaotic atmosphere remains a challenge, but according to William Murtagh of the Space Weather Prediction Center, it is not quite as difficult as predicting the behavior of the sun and the solar storms that ignite the northern lights.

He noted, “I remind the meteorologists, ‘You guys take care of the first 10 miles. I’ll take care of the other 93 million.'”

But solar storm activity has reached a 23-year high and could stay that way for a while. Rob Steenburgh of the center says it’s quite possible that the aurora will appear over the Philadelphia region one night.

“We still have a chance — or chances,” he said. If it happens, expect it to happen no more than a few hours before.

Will another “supermoon” – and a new star – appear soon?

Astronomers tell us that every night a new star as bright as Polaris will appear over Philadelphia. It is the result of a cataclysmic explosion that occurred on a distant nova 3,000 light years ago. It is only a matter of time when the light finally appears. We wait.

The second supermoon in two months is expected to reach full moon on the morning of October 17. It will be the closest full moon to Earth of the year, only about 357,000 kilometers away.

Not only will it appear larger and brighter than other full moons, but it will also technically be far from full when it rises before 6pm on the 16th and 17th, so it will reach its maximum brightness when most people are awake.