This Winter's Cold Near Average...KMA: "Stratospheric Factors Block Cold Air Southward" (Comprehensive)

Temperatures in November and December Similar to Average
January Temperatures Similar or Higher than Average

Arctic Sea Ice Extent at Record Low
Despite La Ni?a Tendency with Low Sea Surface Temperatures

Stratospheric Westerly Wind Variability and Arctic Oscillation East-West Flow to Strengthen
"Unpredictable Occurrence of Unusual Pressure Systems and Blocking"

The above photo is not related to the article. Photo by Hyunmin Kim kimhyun81@

[Asia Economy Reporter Lee Hyun-joo] This winter's cold is expected to be similar to the average of previous years.

On the 26th, the Korea Meteorological Administration (KMA) announced a three-month weather forecast, predicting that temperatures in November and December will be similar to the average, while January is expected to be similar to or warmer than the average. The average temperatures for previous years are 7.0?8.2°C in November, 1.0?2.0°C in December, and -1.6 to -0.4°C in January. Last winter's average temperature was 3.1°C, 0.6°C higher than the average, making it warmer, but this year is expected to be somewhat colder than that.

A KMA official explained, "Due to factors such as the Arctic sea ice extent and the La Ni?a effect, temperatures tend to be lower than average, but stratospheric elements that can raise temperatures are mixed in, so temperatures are expected to be similar to the average."

As of the 23rd, the Arctic sea ice extent has recorded the lowest summer area since satellite observations began in 1979. Since mid-September, Arctic sea ice has been gradually replenishing, but the rate is slower than usual. If the Arctic sea ice does not freeze, cold air can descend into mid-latitude regions, increasing the likelihood of temperatures lower than average. Additionally, when Arctic temperatures rise, the part that creates the upper-level jet stream weakens due to surface temperature differences, loosening the east-west flow of cold air and allowing cold air to move southward into mid-latitude areas.

Impact of Arctic Sea Ice on Atmospheric Pressure (Provided by Korea Meteorological Administration)

On the other hand, the current strong westerly anomaly in the stratosphere suppresses the drop in winter temperatures. When the westerly wind anomaly strengthens, the east-west flow of the Arctic Oscillation intensifies, blocking the southward movement of cold northern air. Considering these factors together, rather than experiencing a sudden cold snap, temperatures are expected to be similar to the average. Strong La Ni?a events occurred in the winters of 1983 and 1998, but 1983 was colder than average, while 1998 was actually warmer.

Temperature fluctuations this winter are expected to be significant. November will experience large temperature differences between day and night due to the influence of mobile high pressure systems, and December through January will see periodic temperature changes influenced by cold and relatively warm air masses. Dry days are expected to be frequent, with precipitation in November and January predicted to be similar to or less than average, and December's precipitation expected to be near average.

Lee Hyun-soo, head of the Climate Prediction Division at the Climate Science Bureau, stated, "Due to climate change based on global warming, there is a possibility of long-lasting unusual pressure systems appearing, or unpredictable blocking events like those that occurred in late July and early August may happen."

This content was produced with the assistance of AI translation services.