Snow levels may drop below 1,000 feet Monday and Tuesday, the National Weather Service says, creating the possibility of 2 to 3 inches on the valley floor.
But snowpack statewide remains well below normal, according to Scott Oviett of the Natural Resources Conservation Service.
“For the entire basin, we started out at about 54 percent,” he said. “The farther north you go, the less the snowpack. Because the winter has been relatively warm, we have received rain and not significant amounts of snow.”
Overnight mid-valley temperatures are expected to fall into the mid-20s starting Monday and lasting through Wednesday. Daytime highs are forecast between 42 and 44 degrees.
Oviett said that if the snow level does drop to 500 or 1,000 feet, higher elevation areas may get enough snow to help make a difference, but it would take several significant snow events to make a major change in overall levels.
“There could be some accumulating snow,” Oviett said. “But it’s yet to be seen if it will make a huge dent."
He said December and January are usually the best months in terms of snowpack accumulation, but both months were mild.
“From a stream flow perspective, we were dry late last year,” he said. “We went into the water year with extremely low stream levels and low soil moisture profiles. We needed rain to build up the soil moisture levels and then put snowpack on top of that.”
According to Oviett, the water year precipitation level is 77 percent. The annual water year measurements start in October.
“We’ve had extended dry periods so far this winter,” he said. “The forecast includes cooler temperatures, which means snow accumulation could increase. Eastern Oregon has rebounded and in some areas, snowpack is closer to normal. But statewide, we are at 67 percent, which reflects the low snowpack on the western side.”
In the Willamette Basin, the snow water equivalent at key measurement sites include: Hogg Pass, 91 percent; Clear Lake, 42 percent; Santiam Junction, 29 percent; Marion Forks, 24 percent.
Basin averages on Feb. 1 were: Willamette, 54 percent; Rogue/Umpqua, 61 percent; Hood/Sandy/Lower Deschutes, 49 percent; Upper Deschutes, 69 percent; Klamath, 70 percent; Lake County/Goose Lake, 97 percent; Umatilla/Walla Walla/Willow, 101 percent; John Day, 93 percent; Harney, 83 percent; Grand Ronde, Powder, Burnt, Idanha, 94 percent; Malheur, 87 percent; Owyhee, 94.
Water levels at Foster and Green Peter reservoirs continue to be lower than usual, according to Salina Hart, chief of reservoir regulation and water quality with the Army Corps of Engineers in Portland.
Hart said the water level at Green Peter is at 945 feet and the Whitcomb Creek boat ramp needs a water level of 970 feet to be accessible.
The Oregon Office of Emergency Management has created an online application called the Oregon Weather Dashboard to illustrate current weather conditions and forecasts using information from the National Weather Service forecasts.
The dashboard uses live Twitter information, high and low temperatures, wind speed, current weather watches and warnings, a three-day precipitation forecast, flood gauge forecasts, current snow depth and wind conditions.
The site can be accessed at the Office of Emergency Management website or at https://geo.maps.arcgis.com/apps/opsdashboard/index.html#/0e771078793440a08e7ccf4c5fbd6d39.