The first day of summer arrived at 4:28 a.m. Monday as an about-face to the cold and damp spring, said Kathie Dello, a faculty research assistant for the Oregon Climate Service at Oregon State University.
The unofficial high temperature almost reached 70, with a forecast calling for high temperatures near 80 today, but whether the summery weather will linger throughout the season is kind of a meteorologic tossup, Dello said.
The National Oceanic and Atmospheric Administration’s summer outlook for the Pacific Northwest predicts roughly equal chances of below-average, average and above-average temperatures and precipitation.
“It’s not strong one way or the other,” she said.
The Western Regional Climate Center records for the Corvallis area in July and August report average high temperatures to be in the low 80s and average lows in the low 50s. Corvallis typically sees less than an inch of rainfall during these months.
The seasonal high-pressure system that usually moves in and settles down off the Pacific Northwest sometime in late May or early June was tardy this year.
Weather statistics back up that it’s been a wet, cold spring:
The .75 inches of rain that fell overnight and was recorded in the 24 hours ending at 8 a.m. on June 2 broke the record of .38 inches for the date in 1947. That wasn’t even the rainiest day of the month, however. In the 24 hours ending at 8 a.m. on June 4, .85 of an inch fell into the rain gauge at OSU’s Department of Crop and Soil Science Hylsop Weather Station on Highway 20. June has so far seen eight days with measurable rain and two days with a trace of rain.
And cold? The spring of 2010 had more than its share. The low of 29 recorded on April 1 tied the 1945 record.
Barb Fick, a horticulture agent for the Benton County office of the OSU Extension Service, said the cold and damp has allowed more fungus growth on Oregon strawberries, but enough sunshine mingled with the rain to give it a touch of sweetness. Gardeners can expect to harvest their tomatoes and other summer vegetables a little later than usual, however.
“We just need to be a little more patient this year,” she said.
Fick said tomatoes ripen more slowly in the Willamette Valley because the cool ocean air rolls in off the Pacific and typically keeps nighttime temperatures low. That makes for more comfortable sleeping weather, but doesn’t provide the ripening power as hot summer nights in the Midwest, for example.
Today’s forecast calls for sunbreaks today, with a high temperature between 75 and 80, a mixture of clouds and sun for the rest of the week, with overnight lows of 45 to 50. Only a small chance of rain is in the forecast.
Looking ahead to winter, far more rain and snow are expected, Dello said. NOAA’s long-range predictions are for a La Nina Watch for this next winter, predicting cooler ocean surface temperatures.
“(La Nina) tilts the odds toward a cooler and snowier winter,” Dello said.
El Nino — the opposite surface-temperature abnormality of La Nina — caused warm surface temperatures in the Pacific over the winter, bringing warmer and drier weather than usual. The snowpack was so low, that forecasters had predicted a summer drought. The spring rains have washed that out of the forecast, however.