Palmer Station, Antarctica Recorded +6.2°C: The Warmest Winter Day in Its History

Palmer Station, the U.S. research outpost located on the Antarctic Peninsula, has just experienced its warmest winter day ever recorded, with the thermometer reaching an astonishing +6.2°C in mid-June 2025.

🌍 A Record-Breaking Event in the Frozen South

Located on Anvers Island, off the western Antarctic Peninsula, Palmer Station typically sees mid-winter highs well below 0°C, with strong winds, heavy snowfall, and temperatures often near –10°C or colder.

Yet on this occasion, driven by a surge of warm, moist air from the north, Palmer Station soared to +6.2°C—a level unprecedented in its winter climate history.

🔍 Causes: Warm Air Advection and Blocking Patterns

The warm spell is linked to several meteorological factors:

A strong atmospheric ridge over the South Pacific channeled subtropical maritime air deep into the Southern Ocean.
A blocking high-pressure system prevented cold polar air from reasserting itself, allowing warmth to persist.

In addition, the Antarctic Peninsula—where Palmer is situated—is one of the fastest-warming regions on Earth, having already seen air temperatures rise by nearly 3°C since the 1950s.

📌 Summary

Location: Palmer Station, Antarctica (Anvers Island)
Date: Mid-June 2025
Record: +6.2°C – Warmest winter day on record at the station
Climatological Significance: A highly unusual midwinter heat event linked to warm air intrusion and broader atmospheric anomalies

This extreme event underscores growing concern about the vulnerability of polar regions to global climate variability. What was once unthinkable—+6°C in Antarctica in midwinter—has now become reality.