Fall is here and so is leaf-peeping weather

As the fall season continues to advance, the beauty of the Inland Northwest is enhanced by the tremendous fall foliage. Between now through the mid- to late-October period should provide some of the best color.

During this time of year, the mixture of reds, purples, oranges and especially yellows will dot the landscape. Some of the trees that are common in the Pacific Northwest include the vine maples, which provides hues of yellow, orange and red. They are often found along many of the hiking trails. The larch and aspen trees will provide yellow and gold colors, which also help make for spectacular displays.

There is a website, www.smokymountains.com, that has a good fall foliage map for the entire country. If you’re looking to travel to see some fall colors, some recommend the Idaho section of the International Selkirk Loop, which goes through Priest River, Sandpoint and Bonners Ferry. The Pend Oreille National Scenic Byway is another good place to see the fall colors.

In the spring and summer months, the green leaves serve as food factories for the tree’s growth. This food-making process takes place in the leaf, which contains a chemical called chlorophyll. This amazing chemical absorbs energy from sunlight and uses it to transform carbon dioxide and water to carbohydrates like sugars and starch. Chlorophyll also gives the leaf its green color.

As we move through the early fall season, changes in daylight hours and temperature cause the leaves to stop their food-making process. The chlorophyll breaks down and the leaf’s green color disappears. The other colors of red, orange and yellow pigments in the leaf now become visible, making for spectacular displays before the leaves eventually fall off the trees. Sugar maples and birch trees often show the most array of color at this time of year.

For the best fall foliage, the trees need moisture during the summer season. Extended periods of abnormal dryness will often lead to leaves prematurely falling off trees and changing colors sooner than normal. The foliage is the most spectacular when there are also sunny days and cool nights in the late summer and early fall. The best colors are from trees that are less stressed. The lack of water in the summer will often lead to more stress for trees, so the fall colors may not be quite as brilliant.

Here in the Inland Northwest, we’ve had one of the hottest and driest summer seasons on record. There will still be a lot of great views in our region, but overall conditions this year may not be as spectacular when compared to other years. But I would still get those cameras ready, as there should still be plenty of color in the coming weeks.

Although the Inland Northwest can provide some breathtaking views, the colors in the Northeast are some of the most amazing I’ve ever witnessed. I lived in Vermont for about 7 years and my late wife and I were lucky enough to see the brilliant display of colors of the hillsides every fall as most of the trees there are sugar maples and birch. If one wanted to take a vacation in the fall, I would certainly recommend a trip to the Northeast sometime in late September or early October. Believe me, it’s worth it.

In terms of our local weather, we continue to be in this drier-than-normal weather pattern across the Inland Northwest. Cliff tells me that we’re seeing one of the driest Septembers in history. About a third of an inch of moisture has fallen at his station this month. Not much rain is expected this week as the big high pressure system dominates, so our moisture total will end up well below the 1.48-inch normal.

However, Cliff and I still see above-normal moisture returning to the region, perhaps starting by the Oct. 8 “new moon” lunar cycle. We should also have an increase in winds as well. Some of the long-range computer models are already beginning to show this change in our weather pattern.

Cliff and I still think that October and November’s precipitation total should be above normal levels as more Pacific storms are expected to move into the region. October’s normal precipitation is 2.22 inches and November’s average moisture total is 3.07 inches.

Snowfall totals may be below average in November if the warmer El Nino sea-surface temperature event forms in the waters of the south-central Pacific Ocean. In fact, we believe that a large portion of the snow for North Idaho should fall around the middle of December into the first few weeks of January. Thanks to the expected warm water phenomenon, El Nino, much of the moisture that does fall in our region this winter season will likely be in the form of rain.

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Contact Randy Mann at randy@longrangeweather.com.