The first hard freeze will bring color to North Idaho

The autumn leaves that each year turn our hills, mountains and valleys into a silent peal of color are one of Ma Nature's most brilliant displays.

They have their own stage, their cast, their audience and, of course, their 'critics' like me.

The past decade has been a bit disappointing for Sharon and me as far as 'leaf-peeping' has been concerned, especially after living in colorful Vermont for nearly 9 years until 2003.

The colors of the leaves, particularly the sugar maples and the birch trees, in New England are spectacular. Randy Mann, his wife Sally, Sharon and I would certainly recommend a trip to Vermont and the surrounding colorful region in early to mid October.

In 1999, Sharon and I took an extensive leaf-peeping bus tour through Vermont and parts of New Hampshire. The leaves were an awe-inspiring mixture of reds, purples, oranges and yellows that sprang from the hills in bursts of golden light.

I'm partially color-blind, but I still enjoyed the trip. Yellow is the 'highlight' of my color spectrum, followed by blue. I'm 'red and green' color-blind. I have trouble with stoplights, especially on rainy nights near dusk. But, in 56-plus years of driving, I've never had a traffic ticket or an accident that was my fault. I've never even had a parking ticket. I'm extremely careful, sort a 'pokey-Joe.' I have to be!

In answering a subscriber's question, it's not so much that the autumn leaves turn yellow, orange, red or purple, but they stop turning green. As Meteorologist Randy Mann says, "the tree's food factory closes down."

This food-making process takes place in the leaf which contains a chemical called chlorophyll, which also give the leaf its green color. This amazing chemical absorbs energy from sunlight that is used to transform carbon dioxide and water to carbohydrates, like sugars and starch.

As we move farther along into the fall season, the shorter daylight hours and cooler temperatures result in the leaves halting 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. The tamarack trees, a type of birch, turn a brilliant gold color late each autumn in the Inland Northwest.

The first hard freeze of the fall season actually 'accelerates' this annual loss of chlorophyll process in the leaves. We did see a light freeze on Friday, Oct. 4, but temperatures were only briefly below 30 degrees.

We do see the chances of a hard freeze arriving in the Coeur d'Alene area by no later than the "full moon" cycle of Oct. 18-25. This is when the leaves will turn color quickly in Camelot. As of this Oct. 10 writing, some of the trees in the backyard are already showing some brilliant colors.

NORTH IDAHO WEATHER REVIEW AND LONG-RANGE OUTLOOKS

Following a warmer than normal first weekend of October with highs near 70 degrees, it turned cool and wet again early this week with highs only in the upper 40s and lower 50s and lows in the 30s and the upper 20s in some of the coldest areas with more light frosts.

Our long-range weather outlook calls for a bit milder temperatures and mostly dry conditions with only brief showers until the arrival of what we believe will be a very chilly and wet Oct. 18-25 "full moon" cycle with snows in the nearby mountains above 4,000 feet. We should see our first hard freezes of the fall of 2013 also at this time.

Our 90-day weather outlook, extending through mid January of 2014, still looks cooler and wetter than normal across the Inland Empire and the northern Rockies.

The first half of the fast-approaching winter of 2013-14 is likely to be snowier than usual, but the second half of the season may actually see less snowfall than normal, if the current extremely weak, chilly 'La Nina' sea-surface temperature event falls apart and becomes a milder 'La Nada' or even a weak 'El Nino' in the waters of the eastern Pacific Ocean. As I said in past weeks, only time will tell. Stay tuned.

Cliff Harris is a climatologist who writes a weekly column for The Press. His opinions are his own. Email sfharris@roadrunner.com