Wet
southern states to contrast drought in West
Photo by Will Collette |
In the U.S. Winter Outlook for December through February, above-average temperatures are most likely across the northern and western U.S., Alaska and Hawaii.
Additionally,
El Nino has a 70 to 75 percent chance of developing.
“We expect El Nino to be in place in late fall to early winter,” said Mike Halpert, deputy director of NOAA’s Climate Prediction Center.
“Although a weak El Nino is expected, it may still influence the winter season by bringing wetter conditions across the southern United States, and warmer, drier conditions to parts of the North.”
“We expect El Nino to be in place in late fall to early winter,” said Mike Halpert, deputy director of NOAA’s Climate Prediction Center.
“Although a weak El Nino is expected, it may still influence the winter season by bringing wetter conditions across the southern United States, and warmer, drier conditions to parts of the North.”
El Nino is an ocean-atmosphere climate interaction that is linked to periodic warming in sea surface temperatures in the central and eastern equatorial Pacific. During the winter, typical El Nino conditions in the U.S. can include wetter-than-average precipitation in the South and drier conditions in parts of the North.
Video
summary of NOAA's 2018-19 Winter Outlook.
Video summary of NOAA's 2018-19 Winter Outlook. (Climate.gov)
Other
climate patterns that can affect winter weather are challenging to predict on a
seasonal time scale. The Arctic Oscillation influences
the number of arctic air masses that penetrate into the South and could result
in below-average temperatures in the eastern part of the U.S.
The Madden-Julian Oscillation can contribute to heavy precipitation events along the West Coast – which could play a large role in shaping the upcoming winter, especially if El Nino is weak, as forecasters predict.
The Madden-Julian Oscillation can contribute to heavy precipitation events along the West Coast – which could play a large role in shaping the upcoming winter, especially if El Nino is weak, as forecasters predict.
The
2018 U.S. Winter Outlook (December through February):
Temperature
Warmer-than-normal
conditions are anticipated across much of the northern and western U.S., with
the greatest likelihood in Alaska and from the Pacific Northwest to the
Northern Plains.
The
Southeast, Tennessee Valley, Ohio Valley and Mid-Atlantic all have
equal chances for below-, near- or above-average temperatures.
No
part of the U.S. is favored to have below-average temperatures.
Precipitation
Wetter-than-average
conditions are favored across the southern tier of the U.S., and up into the
Mid-Atlantic. Northern Florida and southern Georgia have the greatest odds for
above-average precipitation this winter.
Drier-than-average
conditions are most likely in parts of the northern Rockies and Northern
Plains, as well as in the Great Lakes and northern Ohio Valley.
Drought
conditions are likely to persist across portions of the Southwest, Southern
California, the central Great Basin, central Rockies, Northern Plains and
portions of the interior Pacific Northwest.
Drought
conditions are anticipated to improve in areas throughout Arizona and New
Mexico, southern sections of Utah and Colorado, the coastal Pacific Northwest
and the Central Plains.
NOAA’s
seasonal outlooks give the likelihood that temperatures and precipitation will
be above-, near- or below-average, and how drought conditions are expected to
change, but the outlook does not project seasonal snowfall accumulations.
Snow forecasts are generally not predictable more than a week in advance. Even during a warmer-than-average winter, periods of cold temperatures and snowfall are still likely to occur.
Snow forecasts are generally not predictable more than a week in advance. Even during a warmer-than-average winter, periods of cold temperatures and snowfall are still likely to occur.
NOAA’s
Climate Prediction Center updates the three-month outlook each month. The next
update will be available on Nov. 15.
NOAA
produces seasonal outlooks to help communities prepare for what is likely to
come in the next few months and minimize weather's impacts on lives and
livelihoods. Empowering people with actionable forecasts and winter weather tips is key
to NOAA’s effort to build a Weather-Ready
Nation.