The canonical correlation analysis (CCA) forecast of
SST in the central Pacific (Barnett et al. 1988, Science, 241,
192‑196; Barnston and Ropelewski
1992, J. Climate, 5, 1316‑1345), is shown in Figs. F1 and F2. This forecast is produced routinely by the
Prediction Branch of the Climate Prediction Center. The
predictions from the National Centers for Environmental Prediction (NCEP)
Coupled Forecast System Model (CFS03) are presented in Figs. F3 and
F4a, F4b. Predictions from the
Markov model (Xue, et al. 2000: J. Climate, 13,
849‑871) are shown in Figs. F5 and F6. Predictions from the latest version of the
LDEO model (Chen et al. 2000: Geophys. Res.
Let., 27, 2585‑2587) are shown in Figs. F7
and F8. Predictions using linear inverse modeling (Penland and Magorian 1993: J.
Climate, 6, 1067‑1076) are shown in Figs. F9 and F10. Predictions from the ENSO‑CLIPER
statistical model (Knaff and Landsea 1997, Wea. Forecasting, 12, 633‑652)
are shown in Fig. F11. Niño 3.4
predictions are summarized in Fig. F12, provided by the Forecasting and
Prediction Research Group of the IRI.
The CPC and the contributors to the Forecast Forum caution
potential users of this predictive information that they can expect only modest
ENSO Alert System Status: Not Active
is favored during the Northern Hemisphere fall 2019 (~75% chance), continuing
through spring 2020 (55-60% chance).
August, ENSO-neutral continued as reflected by near-average sea surface
temperatures (SST) across most of the central and eastern equatorial Pacific
Ocean (Fig. T18). The monthly Niño-3 and Niño-3.4
indices were -0.1°C and 0.2°C, respectively, with the westernmost Niño-4 region index remaining
above average (0.9°C) and the easternmost Niño-1+2 region index remaining below average
(-0.4°C; Table T2). Upper-ocean subsurface temperature anomalies (averaged
across 180°-100°W) decreased slightly during the month, with below-average
temperatures strengthening in the east-central equatorial Pacific (Fig. T17). Suppressed tropical convection continued over
parts of Indonesia, while near-average convection was evident near the Date
Line (Fig. T25).
Low-level and upper-level winds were near average over most of the
tropical Pacific Ocean (Figs. T20 & T21).
Overall, oceanic and atmospheric conditions were consistent with
majority of models in the IRI/CPC plume (Figs. F1-F12) continue to favor
ENSO-neutral (Niño-3.4 index between -0.5°C and +0.5°C) through the Northern Hemisphere spring. Interestingly, the statistical model averages
favor Niño-3.4 values above the El Niño threshold (+0.5°C) during the fall and winter, while the dynamical
model average indicates values near +0.2°C. Forecasters
are leaning toward the dynamical model average, which is also supported by the
current tendency of the ocean toward cooler conditions. In summary, ENSO-neutral is favored during the Northern Hemisphere fall 2019 (~75%
chance), continuing through spring 2020 (55-60% chance).
updates of oceanic and atmospheric conditions are available on the Climate
Prediction Center homepage (El
Niño/La Niña Current Conditions and Expert Discussions).