Seasonal Forecast

Seasonal Forecast for October-December 2026

Hong Kong is expecting:

1.	normal to above-normal temperature
2.	normal to above-normal rainfall

Assessment (as of 30 September 2026):

Sea surface temperatures of the central and eastern equatorial Pacific stayed above normal for five consecutive months from April to August 2026, and the sum of the sea surface temperature anomalies exceeded 4.0°C. An El Niño event has been established. Based on the latest oceanic observations as well as forecasts by a number of climate models around the world, the warming trend in the central and eastern equatorial Pacific is expected to continue. The El Niño event is expected to peak around November to December this year and to persist at least until spring next year. It is forecast to strengthen into a very strong event, with a chance of becoming the strongest El Niño event on record since 1950.
Under the backdrop of climate warming, October-December temperatures in Hong Kong exhibit a significant long-term increasing trend. The chance of normal to above-normal temperature is generally higher.
Taking into consideration of the latest ENSO status, different climate model forecasts and other objective forecast guidance, the temperature of October-December 2026 in Hong Kong is expected to be normal to above-normal, and the chance of normal to above-normal rainfall will be higher.

Note:

Climate prediction centres around the world generate seasonal forecasts, employing a variety of methods including dynamical models, statistical methods, expert judgment and combinations of them. Predictions from different centres do not always agree and large discrepancies can occur at times. To formulate seasonal forecasts for Hong Kong, the Observatory takes into consideration available products from major climate prediction centres, past performance of climate models, and impacts of El Niño/La Niña, etc.
The Observatory gratefully acknowledges the Tokyo Climate Center of the Japan Meteorological Agency and the National Centers for Environmental Prediction of National Oceanic and Atmospheric Administration, USA for providing dynamical prediction model forecast and hindcast data to support the formulation of seasonal forecast for Hong Kong.
Seasonal Forecast for November 2026-January 2027 will be available around 1st November 2026.

Seasonal forecast charts provided by major climate centres:

For further information on this webpage, please contact Mr. W P Tse (tel:2926 8012, email:wptse@hko.gov.hk)