Renowned climatologist Greg Jones shared some of the latest observations regarding recent weather patterns, and when it comes to the West Coast, his charts are filled with red.
Red is not the color of choice for irrigators and farmers in the Pacific Northwest wine industry, as most of the Cascades in Washington and Oregon indicate less than 25 percent of normal snowpack.
“Sorry for the delay,” Jones wrote in the opening of his latest report, adding he’s been “busier than normal and traveling around speaking on this topic to numerous wine regions in the eastern and western U.S.”
Those traveling across mountain passes in Washington and Oregon have had a much easier time than normal this winter. Anyone driving over Interstate 90 during daylight hours will notice a full reservoir east of Snoqualmie Pass. However, the nearby ski hills are brown and barren of snow, so there’s considerably less snowpack than normal to fill that reservoir and continue to feed the Yakima River — and supply growers in the Yakima Valley.
“Each day without snow accumulation from here on out drops the probability of any recovery closer to being highly unlikely,” Jones wrote.
Summer forecast for 2015 vintage similar to ’14
Jones, professor of environmental science and policy at Southern Oregon University in Ashland, noted that while the 90-day forecast indicates normal spring rains, that precipitation is unlikely to add significantly to the snowpack. And it appears as if the 2015 vintage won’t approach the relatively cool vintages of 2010 or 2011.
“Dynamic seasonal models and historical analogs are all pointing to normal to higher-than-average heat accumulation during the summer — similar to 2013 and 2014.”
Jones, whose father, Earl, is the founding winemaker of Abacela in Roseburg, noted the winter forecasts issued prior to the holidays have proven reasonably accurate, which has meant a dry and warm West Coast compared to the record snows and bitter cold along the East Coast.
In fact, temperatures in Pacific Northwest have ranged from 2-7 degrees above normal, according to the WestWide Drought Tracker, a service sponsored by the University of Idaho’s Desert Research Institute.
“The country continues to experience the dramatic east-west differences due to the strong and persistent ridge in the west (warm, dry) and equally strong and persistent trough in the east (cold, snow),” Jones wrote. “If the winter forecast was off, it was only in the magnitude of the warmth in the west and the amount of snow in the east.”
Nic Loyd, a Washington State University meteorologist, monitors the school’s 160 automated weather stations that make up its AgWeatherNet program to assist farmers throughout the state.
“It hasn’t been very winter-like so far,” Loyd said in a news release. “When it’s been wet, it’s been warm.”
In December, AgWeatherNet measured temperatures in Mount Vernon, Wenatchee, the Tri-Cities, Walla Walla, Moses Lake, Prosser and Moxee. Mean temperatures for the month averaged 3.6 degrees higher than historic averages.
Risk of frost increases with dry spring
Current ocean temperatures indicate growers may well end up worrying more than normal this spring about frost.
“Tropical sea surface temperature conditions show a neutral to mild El Niño, likely fading into summer,” Jones wrote. “Due to the expected weak strength of the El Niño, widespread or significant West Coast to global impacts are not anticipated. North Pacific sea surface temperatures remain much warmer than normal along the West Coast of North America, producing warmer minimum temperatures and helping to hold the ridge in place over the west.
“Taken together, the conditions tilt the odds in favor of a warm and dry late winter/early spring for the west,” Jones continued. “However, dry springs tend to have later individual cold events, where frost frequency goes up with ridges and the inversions they produce in the western valleys.”
Lee Kalcsits, assistant professor of tree fruit physiology at the WSU Tree Fruit Research and Extension Center in Wenatchee, reported tree fruit bud development is about 2½ weeks ahead of schedule.
Stephen Guy, a WSU Extension agronomist, said, “The big message for growers is, you can’t farm by the calendar. You’ve got to farm by the temperature.”