ENSO-neutral is favored (~50 to 55% chance) into the Northern
Hemisphere winter 2017-18.
During June, ENSO-neutral continued, although equatorial sea surface
temperatures (SSTs) remained above average in the central and
east-central Pacific Ocean
[Fig. 1]. The latest weekly Niņo index values were near +0.5°C in
the Niņo-4 and Niņo-3.4 regions, and closer to zero in the Niņo-3 and
Niņo-1+2 regions
[Fig. 2]. The upper-ocean heat content anomaly was above average
during June
[Fig. 3], reflecting above-average sub-surface temperatures across
the central and eastern Pacific
[Fig. 4]. In the atmosphere, tropical convection was suppressed over
the west-central tropical Pacific and enhanced over the Maritime
Continent
[Fig. 5]. The lower-level and upper-level winds were near average
over most of the tropical Pacific, and the Southern Oscillation Index
(SOI) and Equatorial SOI were slightly negative to near-zero. Overall,
the ocean and atmosphere system remains consistent with ENSO-neutral.
Some models predict the onset of El Niņo (3-month average Niņo-3.4 index
at or greater than 0.5°C) during the Northern Hemisphere summer
[Fig. 6]. However, more than half of the models favor ENSO-neutral
through the remainder of 2017. These predictions, along with the
near-average atmospheric conditions over the Pacific, lead forecasters
to favor ENSO-neutral into the winter (~50 to 55% chance). However,
chances for El Niņo remain elevated (~35-45%) relative to the long-term
average. In summary, ENSO-neutral is favored (~50 to 55% chance) into
the Northern Hemisphere winter 2017-18 (click
CPC/IRI consensus forecast for the chance of each outcome for each
3-month period).
This discussion is a consolidated effort of the National Oceanic and
Atmospheric Administration (NOAA), NOAA's National Weather Service, and
their funded institutions. Oceanic and atmospheric conditions are
updated weekly on the Climate Prediction Center web site (El
Niņo/La Niņa Current Conditions and Expert Discussions). Forecasts
are also updated monthly in the
Forecast Forum of CPC's Climate Diagnostics Bulletin. Additional
perspectives and analysis are also available in an
ENSO blog.
The next ENSO Diagnostics Discussion is scheduled for 10 August 2017 .
To receive an e-mail notification when the monthly ENSO Diagnostic
Discussions are released, please send an e-mail message to:
ncep.list.enso-update@noaa.gov.
Climate Prediction Center
National Centers for Environmental Prediction
NOAA/National Weather Service
College Park, MD 20740
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