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We've already surpassed last winter in total snowfall!

| November 29, 2010 8:00 PM

A MODERATE LA NINA CONTINUES IN THE SOUTH-CENTRAL PACIFIC WATERS

Sea-surface temperatures near the West Coast of South America and along the Equator are still much cooler than normal. In fact, over the last few weeks, this new La Nina has continued to slightly intensify. We're still declaring a moderate "La Nina" sea-surface temperature pattern. It's possible that we could see a strong La Nina, if we see further cooling continue in this region.

Cooler waters have also expanded in the Gulf of Alaska and south of the Hawaiian Islands. However, there has been some minor weakening of La Nina north of the Equatorial regions over the last few weeks.

Since the middle of October, La Nina has strengthened overall. It appears that this moderate La Nina will be with us through at least early 2011, probably longer.

During the warmer El Nino events, the Sub-Tropical Jet Stream becomes stronger and moisture flows along that path into California, the Desert Southwest, Texas and the Deep South in a pencil-like "straightline" course.

During the cooler La Nina event, the Maritime Polar Jet Stream often becomes stronger and the Sub-Tropical Jet Stream is much weaker. The northern portions of the U.S. usually receive higher snowfall totals and colder temperatures. We're already seeing this pattern with increasing moisture in the northwestern and northeastern portions of the country, including snowy North Idaho.

Ocean temperatures near Ecuador and Peru are still about 3-6 degrees below normal levels. Readings along the Equator are not quite as cool at this time.

The Southern Hemisphere is entering the end of its spring season, so it's possible that we may see further cooling of the Equatorial waters between now and at least mid-December, probably longer. Before 2010 expires, we may start to see warming sea-surface temperatures as the Southern Hemisphere goes into its summer season, but only time will tell.

For the upcoming winter season, if La Nina continues to maintain its strength, or even intensify, conditions north of I-80 are expected to be much colder and snowier than normal as the Polar Jet Stream intensifies. We've already seen this pattern develop across the North Country.

SOLAR STORMS SEEM TO BE INCREASING ... FOR NOW

Solar activity has been slowly increasing over the last several weeks. There was a high of 74 sunspots on Oct. 26. Within the last several days, solar activity has averaged between 55 and 65 sunspots, an increase from last week. Based on the current data, it appears we're still in a "back-and-forth" pattern of solar activity, but there seems to be a trend developing toward higher solar activity.

During the "peak" of solar activity in late 1990s, we were seeing 200-300 solar storms each day. The next solar "maxima" cycle is due in late 2012 or early 2013. So far, there isn't a strong indication of a dramatic rise in solar activity, but that could change quickly. Many scientists suggest that the upcoming maxima will be very strong, but there hasn't been much evidence yet to support this possible event. Again, stay tuned.

NORTH IDAHO WEATHER REVIEW AND LONG-RANGE OUTLOOKS

It's snowing lightly this day after Thanksgiving in beautiful, but bustling, Coeur d'Alene. Another winter storm warning was in effect through 4 p.m. on Saturday, Nov. 27, for the Inland Empire.

Most of the area ski resorts are open and expecting large crowds of skiers and snowboarders on the snow-packed slopes. The top of Silver Mountain reported more than 30 inches of the white stuff early Friday.

Since the snows began on Nov. 18, locally at my station on Player Drive in northwest Coeur d'Alene, we've measured nearly 20 inches of snow, easily surpassing the entire seasonal snowfall total of last winter in 2009-10 of a puny 18.1 inches, the ninth least snowfall on record since at least 1895, thanks to a warm and dry El Nino event in the tepid waters of the Pacific Ocean.

If I'm right, this November will turn out to be the second snowiest on record to the 31.6 inches that we measured in Coeur d'Alene in November of 1973. Our normal November snowfall in town is just 7.8 inches. We should reach at least 26 to 28 inches for the month before it ends Tuesday evening, Nov. 30. Last November in 2009, we gauged just 4.9 inches of snow.

I'm still expecting that this La Nina-enhanced 2010-11 winter season will produce at least 80 inches of snow in Coeur d'Alene with upwards of 100 inches or more to the north and east of town. The area ski resorts may exceed 280 inches of total snowfall.

Temperatures will average around 4 to 5 degrees below normal this winter compared to 4 to 5 degrees above normal last season in 2009-10 during El Nino.

Last Tuesday morning, Nov. 23, we dipped to a record low for the date of -9 degrees, just four degrees above the all-time November low reading of -13 degrees observed on Nov. 27, 1896, more than a century ago. It was a frigid -11 degrees at Hayden, Rathdrum and Hauser Lake.

As of 10 a.m. on Friday, Nov. 26, we had been below the freezing mark for nearly six full days, the third longest November deep freeze since a least 1895. Ironically, our first killer-type freeze didn't occur this fall until Saturday morning, Nov. 20. We still had tomatoes ripening on the window sills in Sharon's kitchen.

Only November of 1985, with 8 days in a row of sub-freezing weather, and November of 1896 with 7 days and 8 hours under 32 degrees were colder. I'm expecting that our current sub-freezing streak will end Friday afternoon, mighty close to the November record for persistent cold.

What a difference La Nina makes!

LATE NOTE (Sunday, 3 p.m.)

We need just 2 inches of additional snow by 11:59 p.m. Tuesday to break the all-time November snowfall record of 31.6 inches in 1973.

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