Like summer, autumn in Greece is expected to be unusually warm, according to the Hellenic National Meteorological Service (HNMS).
The HNMS has presented forecast data indicating that average temperatures from September through November could rise as much as two degrees Celsius above the seasonal norm. This trend may continue into winter, particularly in the western and southern regions of the country.
HNMS predicts especially warm post-summer weather
The HNMS’s autumn forecast shows a continuation of the hot conditions that characterized the summer months in Greece. Specifically, the models indicate that temperatures could be between 1 and 2 degrees Celsius higher than usual, especially in western Greece.
While the European Centre for Medium-Range Weather Forecasts (ECMWF) predicts similar increases for the rest of Greece, the multi-model system used by the HNMS suggests a more moderate rise of 0.5 to 1 degree Celsius across the country.
Understanding predictions on temperature deviations and climatology
It’s important to note that the forecast models used by the ECMWF and the multi-model system rely on climatology data from 1993 to 2016. This means the temperature deviations are measured against the average values from that period, providing a reliable comparison to typical seasonal norms
The maps are available from the C3S (Copernicus) service and can be located together with the results of all models and parameters, based on the C3Smulti-model system, on the website.
Projections for autumn indicate a strong likelihood—over 80 percent probability—that Greece will experience particularly warm conditions. The models continue the pattern of positive temperature deviations observed during the summer across much of Europe.
While most of Europe, including regions such as Spain, Italy, the Balkans, Turkey, and parts of Scandinavia, will likely see temperature increases of 1 to 2 degrees Celsius, the only significant exception is the region between Iceland and Greenland, where negative deviations are expected.
The ECMWF predicts widespread temperature increases across Europe. However, the multi-model system takes a more conservative approach. It forecasts fewer areas with deviations greater than 1 degree Celsius. These differences arise from the multi-model’s structure, which combines various climate models for a comprehensive forecast.
Despite these slight differences, the models generally agree, enhancing the reliability of the predictions. This agreement signals a strong likelihood of a warmer than usual autumn in Greece.
Weather patterns and climate influence: what lies ahead for Greece
The autumn forecast also predicts changes in precipitation and atmospheric pressure. The ECMWF map highlights negative pressure deviations east of Iceland and across Scandinavia. The multi-model system also indicates similar patterns in these regions. These pressure variations play a significant role in influencing weather patterns across Europe, including Greece.
Key climate factors show that neutral atmospheric pressure is expected between Iceland and the Azores, suggesting a neutral effect on Greece’s autumn weather. There is potential for a transition to a La Niña phase. This can impact global atmospheric circulation. The summer forecast anticipated a La Niña phase, which now seems likely to continue into winter. Forecast maps show negative sea surface temperature deviations between Australia and South America.
Greece should prepare for an unusually warm autumn, with this trend possibly extending into winter. The exact impacts are uncertain, but the forecasts suggest above-average temperatures in the coming months.
