The lack of rain this year could elicit a dazzling side effect
in the fall: exceptionally colorful leaves. That's because
below-average rainfall in the Northeast may cause trees to shut
down production of a chemical called chlorophyll earlier than
usual. Without it, various pigments like carotenes and
xanthophyll (yellow to orange) and anthocyanins (red) visually
emerge, reports LiveScience. Water scarcity causes stress in
trees, which leads to an earlier-than-usual preparation for
winter and the switch-off of chlorophyll. The fall display will
still be vivid as long as days are sunny and nights cool, says a
researcher, but a particularly harsh drought will make leaves
die and break off. It's a bit early to tell just how spectacular
the arboreal show will be this year because the colors are not
at their pinnacle until October.