|NOAA El Niņo watch signals a possibility of a temperate winter posted on 10/01/2018|
Although the fall colors have begun in the Mount Hood
region, winter is already predicted to arrive later and to be warmer and drier
then the past two years.
The National Oceanic and Atmospheric Administration (NOAA)
winter weather outlook for 2018-19 predicts a 70 percent chance of El Niño
conditions developing this winter, resulting in higher-than-average
temperatures with lower-than-average precipitation in the Pacific Northwest.
The scientists at NOAA use global weather patterns as well as the development
of El Niño or La Niña conditions to make their seasonal forecasts.
“It’s kind of (looks like) what we expect with an El Niño
winter, a mild winter,” said David Bright, meteorologist with the National
Weather Service in Portland.
El Niño and La Niña are opposite phases of the El
Niño-Southern Oscillation (ENSO) cycle. The ENSO cycle is a scientific study of
the temperature fluctuations between atmospheric and ocean temperatures in the
Of these two phases, La Niña is considered to be the cold
phase of the ENSO cycle, and El Niño is considered to be the warmer phase.
Bright stated that tropical water temperatures are currently
a degree higher in the central Pacific, which is in the weak to moderate range
for El Niño conditions.
In the Pacific Northwest there is a 50 to 55 percent El Niño
prediction from September through December, with above-average temperatures and
This suggests the possibility of a slow start to winter
conditions in the Northwest with drier conditions in the fall.
In mid to late winter, January through March there is a 70
percent El Niño prediction with above-average temperatures predicted and
equal-to-average chances of precipitation after the new year.
“Precipitation signals are weaker with El Niño conditions,”
Bright said. He added it was hard to predict if the condition would impact the
amount of precipitation on the mountain, but that the winter would be milder
overall. “Let’s hope we fill the reservoirs and get some snow on the ground for
“Both 2016-17 and 2017-18 were La Niña, which tends to be a
cooler, wetter winter,” Bright added. “We’re looking at a milder winter.”
As recently as 2017-18 the Northwest received higher levels
of precipitation then the initial NOAA forecast.
Current information about the ENSO El Niño Watch can be
found online at https://www.climate.gov/enso.
By Benjamin Simpson/MT