Itís certainly been a chilly weather pattern east of the Rockies in November. Parts of the Northeast had one of the coldest Thanksgiving holidays in recent memory. It was cold enough that rare early snowfalls were reported down into the panhandles of Texas and Oklahoma as well as into Arkansas.
Here in Coeur díAlene, our big weather change is here as near-record rainfall was reported last week. From Nov. 21 to Nov. 30, Cliff measured 2.71 inches of moisture, with .79 inches falling on the 27th.
Thanks to the big storms at the end of last month, precipitation totals for November did finish well above normal as our weather pattern finally flipped to the wetter side. Cliff measured 4.36 inches of rain and melted snow last month. The normal for November is 3.07 inches. However, snowfall was well below average levels. We normally see 8.7 inches in Coeur díAlene, but managed to get just 2.9 inches of snow.
More valley rain and mountain snows are expected across our region, but Cliff and I do believe that our chances for snow will increase in the lower elevations as early as next week. As always, itís always ďa temperature thingĒ here in North Idaho. A few degrees will often make all the difference in the world in terms of rain or snow.
As Iíve mentioned in previous columns, ocean temperatures are continuing to warm up in the waters of the south-central Pacific Ocean. Weíre getting very close to having a warm El Nino declared. According to Australian scientists, there is a very good chance that weíll have an El Nino this winter and it will continue at least through the spring of 2019.
The tremendous warming of ocean waters will be pumping more warm air into the atmosphere, especially during the second half of the winter season. Many storms that move into our region will likely be moderated to the warmer side over at least the next 2-3 months. Weíll just have to wait and see. Remember, during years with warmer-than-normal sea-surface temperatures, our annual snowfall totals are often much lower than normal. For the 2018-19 season, Cliff and I are predicting around 50 inches of snow in Coeur díAlene, compared to the normal of 69.8 inches.
As is often the case during El Nino years, much of the moisture that does fall in our region comes in the form of rain rather than snow as the air masses are too warm. But, we have seen a number of Decembers during an El Nino that have produced above-normal amounts of snow. Therefore, Cliff and I believe we still have a decent chance for a fourth consecutive white Christmas. Based on climatological history, Cliff says when weíve had three years in a row with a white Christmas, there has always been a fourth.
The biggest concern with a new El Nino is the increased probability of ice in the lower elevations. Many can remember the big ice storm on Nov. 19, 1996, across the Inland Empire.
During that time, the region experienced a pattern of very cold air settling into the lower elevations. Temperatures at the surface were near or below freezing on that November day. However, readings were much warmer from above the surface to near 6,500 feet.
Since the air temperature above the surface was above freezing, the rain drops did not change to snow. They became ďsupercooledĒ when they hit the ground as rain, and once they came in contact with buildings, power lines or other objects that were below freezing, the rain drops froze almost instantly. These are the conditions for freezing rain and ice storms.
In November 1996, about an inch and a half of rain fell on the frozen surface. There was also freezing fog, snow and mist. It was a mess as trees and branches were coming down due to the heavy weight of the ice. Ice-covered power lines and transformers were exploding as over 100,000 people lost power. It was the worst outage in over 100 years.
Other structures like homes, buildings and vehicles were caked with layers of ice up to an inch thick. Damage was about $22 million in Spokane and Kootenai County.
The massive ice storm in November 1996 occurred during the second strongest El Nino in recorded history. The biggest El Nino happened in 2016 and we were fortunate not to see any major incidents of ice. The expected El Nino is expected to be much weaker, but that doesnít mean we wonít see any icy weather.
Therefore, itís quite possible that we could be dealing with periods of freezing rain over the next few months. Letís hope that we donít get a big ice storm like the one seen over 20 years ago.
Contact Randy Mann at firstname.lastname@example.org