Forget that bet over whether this summer's early drought or late rain will make fall leaves brighter or duller.
Those hues are mostly up to the weather ahead, according to leaf expert Marc Abrams, professor of forest ecology and physiology at Penn State University's College of Agricultural Sciences. For brilliant leaves, hope for sunny days with cold crisp nights.
"This has been a very complicated year," he said. "The Pittsburgh area had significantly more drought than we had in Central and Eastern Pennsylvania, and I think the drought is going to be a factor against the best fall colors that are possible. But my guess is that most of your trees held up OK."
What's most important, from here on out, is dry weather with night temperatures dipping into the 40s and 30s, but not freezing, said Mr. Abrams, who devoted his career to studying how weather affects fall colors.
"Earlier in September we had some nice, cool temperatures that started to bring out the color. I would like that to continue," he said. "What would be most worrisome would be a continuation of warm weather into the second week in October and not getting the cool-down that we need."
Dave Jackson, a forest resources educator with Penn State Extension Service, says that the most spectacular foliage in Pennsylvania is north of Interstate 80, in places such as the Allegheny National Forest. That's because the hardwoods, such as cherry and sugar maple, that thrive there offer a greater variety of spectacular colors than the duller oaks and predominant red maples in the southern part of the state.
Look for the northern hardwoods to start turning in mid-October, the southern oaks in late October, he said.
"The oaks will have more of the oranges and not so much of the brilliant reds," he said.
He recommends The Pennsylvania Wilds site at www.pawilds.com for directions to some of the best foliage in northcentral Pennsylvania.
Closer to home, perennial popular places to view foliage are:
• Raccoon Creek State Park in Hookstown. Some leaf connoisseurs take the 60-mile drive south on Route 18 from the park to Waynesburg.
• Ohiopyle State Park, including Route 381 running into and through it. Both parks are at www.dcnr.state.pa.us.
• On the northern side of the Laurel Highlands, the stretch of Route 30 from Latrobe through Ligonier to the Flight 93 National Memorial offers spectacular foliage and history lessons from the French and Indian Wars through 9/11. www.laurelhighlands.org .
If you prefer to watch while someone else steers, the Gateway Clipper will offers seven fall foliage river cruises. Information is at www.gatewayclipper.com.
Ann Rodgers: firstname.lastname@example.org or 412-263-1416.