ENSO-neutral conditions are favored to continue
through at least the Northern Hemisphere spring 2017, with
increasing chances for El Niņo development into the fall.
La Niņa conditions are no longer present, with slightly below-average
sea surface temperatures (SSTs) observed across the central equatorial
Pacific and above-average SSTs increasing in the eastern Pacific
[Fig. 1]. The latest weekly Niņo index values were -0.3°C in the
westernmost Niņo-4 and Niņo-3.4 regions, and +1.5°C in the easternmost
Niņo-1+2 region
[Fig. 2]. The upper-ocean heat content anomaly increased during
January and was slightly positive when averaged across the eastern
Pacific
[Fig. 3], a reflection of above-average temperatures at depth
[Fig. 4]. Atmospheric convection remained suppressed over the
central tropical Pacific and enhanced over Indonesia
[Fig. 5]. The low-level easterly winds were slightly enhanced over
the western tropical Pacific, and upper-level westerly winds were near
average. Overall, the ocean and atmosphere system is consistent with
ENSO-neutral conditions.
Most models predict the continuation of ENSO-neutral (3-month average
Niņo-3.4 index between -0.5°C and 0.5°C) through the Northern Hemisphere
summer
[Fig. 6]. However, a few dynamical model forecasts, including the
NCEP CFSv2, anticipate an onset of El Niņo as soon as the Northern
Hemisphere spring (March-May 2017). Because of typically high
uncertainty in forecasts made at this time of the year for the upcoming
spring and summer, and the lingering La Niņa-like tropical convection
patterns, the forecaster consensus favors ENSO-neutral during the spring
with a ~60% chance. Thereafter, there are increasing odds for El Niņo
toward the second half of 2017 (~50% chance in September-November). In
summary, ENSO-neutral conditions have returned and are favored to
continue through at least the Northern Hemisphere spring 2017 (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 13 April 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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