# Global severe weather and tropical instability

> Live situation record from CLSTR: https://clstr.news/situations/global-severe-weather-and-tropical-instability
> Updated: 2026-09-11T17:17:53.000Z. Sources: 94. Developments: 2.

Severe weather conditions have been reported across multiple countries, including Spain, Italy, Argentina, and Costa Rica. In Spain and Italy, authorities have activated emergency protocols and suspended public services due to risks of intense thunderstorms, flooding, and hydrogeological hazards.

In Costa Rica, the weather situation has evolved into a period of sustained atmospheric instability. Following initial warnings of high winds and scattered rainfall, the passage of consecutive tropical waves—specifically waves No. 42 and No. 43—is expected to bring continued heavy rainfall. Significant accumulations have already been recorded in the South Pacific and Central Valley. Authorities have warned of potential flooding from saturated drainage systems, electrical storms, and wind gusts up to 80 km/h, which may impact infrastructure, power lines, and maritime navigation.

## Timeline

### 2026-09-11: Costa Rica weather alert: Consecutive tropical waves to bring heavy rain

Costa Rica faces heavy rainfall and atmospheric instability as tropical waves 42 and 43 pass through, bringing risks of flooding, strong winds, and rough seas through the weekend.

2 sources. https://clstr.news/cluster/costa-rica-weather-alert-consecutive-tropical-waves-to-bring-heavy-rain

### 2026-09-07: Severe weather alerts issued across Spain, Italy, Argentina, and Costa Rica

Severe weather alerts for heavy rain, thunderstorms, and high winds are active across Spain, Italy, Argentina, and Costa Rica, prompting emergency protocols and service suspensions.

93 sources. https://clstr.news/cluster/spain-weather-forecast-storms-and-rain-expected-in-barcelona-and-valencia

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Cite as: Global severe weather and tropical instability. CLSTR, https://clstr.news/situations/global-severe-weather-and-tropical-instability