803 

FXUS24 KWNC 141307

PMDENS

El Nino/Southern Oscillation (ENSO) Diagnostic Discussion

NWS Climate Prediction Center College Park MD

900 AM EDT Thu 14 Aug 2025



NOTE: figures mentioned in the discussion are available on

the internet at HTTP://WWW.CPC.NCEP.NOAA.GOV



ENSO Alert System Status: La Nina Watch



Synopsis: ENSO-neutral is most likely through the late

Northern Hemisphere summer 2025 (56percent chance in

August-October). Thereafter, a brief period of La Nina

conditions is favored in the fall and early winter 2025-26

before reverting to ENSO-neutral.



During the past month, ENSO-neutral continued, with near-average

sea surface temperatures (SSTs) established across most of

the equatorial Pacific Ocean (Fig. 1). With the exception

of the easternmost Nino-1+2 index (+0.8degC), the latest

weekly Nino SST index values ranged from -0.3degC to +0.0degC

(Fig. 2). Subsurface temperature anomalies in the eastern

Pacific Ocean became weakly negative over the past month

(Fig. 3), with below-average temperatures generally observed

between 25- and 200-meters (Fig. 4). Low-level wind anomalies

were easterly over the east-central and eastern tropical

Pacific, while upper-level wind anomalies were westerly over the

west-central and eastern tropical Pacific. Convection remained

enhanced over a small region of Indonesia and was suppressed

over the western tropical Pacific (Fig. 5). Collectively,

the coupled ocean-atmosphere system in the tropical Pacific

reflected ENSO-neutral.



The IRI predictions indicate ENSO-neutral is most likely

to persist through the Northern Hemisphere winter 2025-26

(Fig. 6). However, similar to last month, the North American

Multi-Model Ensemble favors La Nina conditions for a short

duration during the Northern Hemisphere fall and early

winter. Based on this guidance and recent changes in the

tropical Pacific, the forecast team narrowly favors La Nina

thresholds being reached in three overlapping, 3-month seasons

(Nino-3.4 index ≤ -0.5degC during September-November,

October-December, and November-January). In summary,

ENSO-neutral is most likely through the late Northern Hemisphere

summer 2025 (56percent chance in August-October). Thereafter,

a brief period of La Nina conditions is favored in the fall and

early winter 2025-26 before reverting to ENSO-neutral (Fig. 7).



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 website (El Nino/La Nina Current Conditions and Expert

Discussions). A probabilistic strength forecast is available

here. The next ENSO Diagnostics Discussion is scheduled for

11 September 2025. 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.







$$