Uruguay Braces for Late-December Heat Spike, With Some Areas Forecast Above 40°C

Uruguay entered the last week of the year with a sharp warming trend that local forecasters say will peak midweek and then ease around New Year’s Day.

In interviews carried by El Observador and republished by La República, meteorologists Mario Bidegain and Nubel Cisneros said Montevideo could reach about 36–37°C.

Parts of the southwest, notably Soriano and Colonia, and the north, center, and litoral regions could climb past 40°C during the hottest window. The official forecast nuance is important.

Uruguay’s national weather service, Inumet, warned of “high temperatures” and said maximums would generally sit around 31–35°C, rising to localized 36–38°C from Monday 29 December, mainly south of the Río Negro, and lasting “in principle” through Thursday 1 January 2026.

But Inumet also stressed that minimum temperatures were expected to be much lower (around 14–18°C), which means the event might not meet the technical threshold for an “ola de calor” under official definitions, even if afternoons feel intense.

That difference—“feels like a heat wave” versus “meets the formal criteria”—is why you’ll see mixed wording across media and social feeds.

Uruguay’s emergency-management guidance (SINAE) defines a heat wave as at least three days with both high maximums and high minimums (hot nights), because that’s when the body gets less overnight relief and health risks rise fastest.

Inumet’s point is that cooler nights can reduce the sustained stress, even when daytime highs are punishing.

This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error