El Nino pattern combined with high pressure system spells greater likelihood of inversions and drier than usual conditions

The long-term forecast calls for wintry weather the next three months.

But don't expect to see an abundance of snow, particularly in the mountains, and at lower elevations, conditions could likely bring more inversions to the Crook County area as well as a greater likelihood of freezing rain.

"We are in an El Nino pattern," explains Joe Solomon, a meteorologist with the National Weather Service in Pendleton. "When there is warmer-than-normal sea surface temperatures across the tropics of the Pacific Ocean, that is what we call an El Nino pattern, and it has an impact on the global weather patterns."

Solomon said that such a weather pattern usually results in drier than normal conditions in the Pacific Northwest as well as higher temperatures than usual.

"For the December, January, February time period, the outlook is calling for above normal temperatures across all of the western United States, but really focused on the Pacific Northwest," he said.

While that is true on large scale, other factors will cause areas like Central Oregon to see some conditions that seem to buck the overall trend. Solomon said that the El Nino pattern tends to leave the Central and Eastern Oregon areas under a ridge of high pressure.

"When we get under a ridge of high pressure, we get fog," Solomon explained. "That high pressure just puts a lid on everything. Yes, it's warmer in the mountains, but we tend to have fog trapped in the Columbia Basin that even moves into Central Oregon over time. So even though the outlook is calling for warmer-than-normal conditions, when you break it down to local conditions, it could mean we are a foggier situation than normal."

Solomon went on to note that the stagnant weather pattern, with high pressure over the area for a prolonged period of time, not only traps fog and low clouds, it creates an inversion where temperatures are colder than normal at lower elevations and warmer than normal in the mountains.

"We are still going to have occasional weather systems coming through, and they are going to produce precipitation," he said, "but under this pattern, it would actually set up to be freezing rain or would be prime conditions for ice events."

Meanwhile, up in the mountains, the likelihood of a strong snowpack is diminished because of the warmer temperatures.

"If we do get snow, it will tend to melt off in the mountains and there could be more rain than snow," Solomon said.

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