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The recent spate of heavy snows amid strangely behaving storm fronts has caused Southern Oregon's snowpack to do a big U-turn, creeping this week above normal after spending almost the entire winter in the red. The Rogue River Basin limped into mid-January with a snowpack of just two-thirds of normal, but it reached average levels Monday and climbed Tuesday to 106 percent of normal — with more snow still falling. While the numeric change appears like a great hydrological victory, think of it more like getting your cholesterol levels back to normal after a decade of bacon breakfasts. “It sounds great, but we’re thinking in terms of the past 10 years when we’ve seen such reduced snowpack in the area that actually being near normal is a great change for us,” said Scott Oviatt, supervising hydrologist. Earlier forecasts called for a warmer and drier winter in Southern Oregon, and that pattern largely came to fruition as the jet stream repeatedly carried moisture to the north and south of the region, Oviatt said. By Jan. 16, the Rogue Basin’s snowpack was at 67 percent of average, but that quickly changed when the jet stream dropped down here, thanks in part to a “polar vortex spinoff” from hideously cold weather crippling the Midwest, Oviatt said. “It maintained that pattern,” Oviatt said. “It’s a welcome change from what we’ve seen.” The change has been as dramatic as it has been unusual. In the past week, the snowpack at Siskiyou Mountain’s Bigelow Camp at 5,130 feet above sea level west of Applegate Lake has risen from 106 percent of average to 164 percent of average, according to the Natural Resources Conservation Service. At Sevenmile Marsh in the Cascades south of Crater Lake, the snowpack has leapt from 87 percent of average to 114 percent of average in the past week, according to NRCS records. “It’s rare to have that amount difference in a week, especially in February,” National Weather Service meteorologist Brian Nieuwenhuis said. “This system is not behaving like a typical system,” Nieuwenhuis said. The recalcitrant front was forecast to switch to rain before moving out of the valley Tuesday, replaced by a series of new fronts, “but nothing this strong, this cold and this wet,” Nieuwenhuis said. The fact that more than a third of the snowpack has come so late in the winter doesn’t statistically raise the specter of ensuing flooding. Most Rogue Basin floods typically occur when warm rains rapidly obliterate snowpack regardless of when that snowpack was accrued, and no such event is on the immediate horizon, Oviatt said. “The positives far outweigh the negatives,” Oviatt said. “We’ll take the higher amount.” The return to normal means area reservoirs appear to be edging closer to potential water levels at par for future needs of irrigators and Rogue Basin salmon and steelhead, which rely on supplemental summer flows. Lost Creek and Applegate reservoirs — the two main Rogue Basin flood-control projects — were both still sporting elevation levels Tuesday a few feet below the normal February filling curve. Lost Creek Lake had been on its filling schedule since Jan. 1, but the U.S. Army Corps of Engineers put back on its flood-control hat briefly Monday when it lowered Lost Creek water releases from an already low 1,050 cubic feet per second to the bare minimum of 500 cfs. Kevin McAllister, the Corps’ Rogue Basin hydrologist, said in an email that the move was to help keep the Rogue from flooding at Dodge Bridge where Highway 234 crosses the river. The Corps’ flood-control goal at Dodge Bridge is to keep flows below 20,000 cfs, and flows did creep up to a record high for Feb. 25 of 18,500 cfs at 4 p.m. Monday before dropping quickly to under 4,600 cfs by Tuesday morning, according to the U.S. Geological Survey. High winter flows like those seen Monday can wash incubating wild spring chinook salmon eggs out of the Rogue’s gravel beds and kill them. However, computer models predict that infant spring chinook eggs laid before Sept. 20 — right around the peak of wild spring chinook spawning in the Rogue — have hatched and could ride out the high water, said Pete Samarin, fish biologist for the Oregon Department of Fish and Wildlife. Reach Mail Tribune reporter Mark Freeman at 541-776-4470 or [email protected]. Follow him on Twitter at www.twitter.com/MTwriterFreeman.