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
. The predictions from the National Centers for
Environmental Prediction (NCEP) Coupled Forecast System Model (CFS03) are
presented in Figs. F3 and F4a,
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 Scripps / Max
Planck Institute (MPI) hybrid coupled model (Barnett et al. 1993: J.
Climate, 6, 1545‑1566) are shown in Fig. F11.
Predictions from the ENSO‑CLIPER statistical model (Knaff and
Landsea 1997, Wea. Forecasting, 12, 633‑652) are shown in
Niño 3.4 predictions are summarized in Fig. F13,
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 skill.
ENSO-neutral conditions are expected to prevail during the
next 3-6 months.
The patterns of anomalous ocean temperatures and atmospheric circulation
during June 2006 were consistent with ENSO-neutral conditions in the tropical
Positive SST anomalies expanded eastward during the month, with SST
anomalies greater than +0.5C observed in most of the
equatorial Pacific between 130ºE and 140ºW (Fig. T18).
As a result positive SST anomalies were observed in both the Niño 4
and Niño 3.4 regions, while anomalies remained near zero in the eastern
equatorial Pacific (Niño 3 and Niño 1+2 regions) (Table T2
and Fig. T5).
The equatorial subsurface temperature anomaly pattern featured negative
anomalies in the far eastern Pacific and positive anomalies in the western
and central Pacific during June 2006 (Fig. T17). Beginning
in February the area of positive
anomalies at depth has expanded to the east (Fig.
T15), and the basin-wide upper ocean heat content increased.
Low-level (850-hPa) and upper-level (200-hPa) winds over the tropical
Pacific were near average during the month (Figs.
T20 and T21).
Collectively, these atmospheric and oceanic features indicate ENSO-neutral
The value of the Oceanic Niño Index (ONI; 3-month running mean average of SST anomalies in
the Niño 3.4 region – computed
using the Extended Reconstructed SST version-2 data set) for April -
June 2006 is 0.0°C, which
indicates ENSO neutral conditions.
Most of the statistical and coupled models predict slightly positive
SST anomalies (ENSO-neutral to weak El Niño)
in the Niño 3.4 region
through the end of 2006 (Figs. F1,
F2, F3, F4a,
F4b, F5, F6,
F7, F8, F9,
F10, F11, F12
forecasts are consistent with the recent build up in upper-ocean heat content
along the equator. Since the low-level easterlies have been near average, it
seems likely that ENSO-neutral conditions will continue at least for the next
three months. However, the spread of the forecasts (ENSO-neutral to El Niño)
indicates considerable uncertainty in the outlook for late 2006 and early
updates of SST, 850-hPa wind, OLR and features of the equatorial subsurface
thermal structure are available on the
Center homepage at: