# Southwest United States

Type: region

Source: Climate Intelligence Brief — https://getclimatebrief.com/entity/southwest-united-states
Canonical HTML page: https://getclimatebrief.com/entity/southwest-united-states

## Timeline

- **2026-03-20**: Record Heat — Multiple cities in Arizona and Nevada record their highest-ever temperatures for the month of March.
- **2026-03-20**: Scientific Warning — Climatologists issue a formal briefing on the 'parade of ultra extremes' and its long-term implications.
- **2026-03-15**: High Pressure Ridge — A persistent high-pressure system begins building over the Southwest US.
- **2026-03-15**: Temperature Records Shattered — Phoenix and Las Vegas record their hottest March days in history, exceeding 95°F.
- **2026-03-10**: Heat Dome Formation — A high-pressure system begins to stall over the Southwest, trapping warm air.
- **2026-02-20**: Atmospheric Rivers — Extreme precipitation events impact the West Coast, highlighting weather volatility.
- **2026-02-15**: Snowpack Peak — Regional snowpack levels peak early due to unseasonably warm February rains.
- **2026-01-15**: Global Records — January 2026 is confirmed as the warmest January on record globally.

## Recent coverage (2 stories)

### Southwest Heatwave Signals New Era of 'Ultra-Extreme' Climate Events
2026-03-20 09:38:50 · Sentiment: Bearish · Impact: 7/10 · Sources: 2

An unprecedented early-season heatwave across the Southwest United States has scientists sounding the alarm over a 'parade of ultra extremes.' This event underscores the accelerating impact of climate change as regional temperature records are shattered months before the traditional peak of summer.
Full story: https://getclimatebrief.com/story/southwest-heat-ultra-extremes-climate-analysis

### Unseasonable Southwest Heatwave Signals Accelerating Climate Volatility
2026-03-20 09:36:43 · Sentiment: Bearish · Impact: 7/10 · Sources: 5

An unprecedented early-season heatwave in the Southwest United States is shattering March temperature records, marking the latest in a series of global weather extremes. This unseasonable surge is straining regional power grids and threatening critical water resources ahead of the traditional summer peak.
Full story: https://getclimatebrief.com/story/southwest-heatwave-extreme-weather-2026

---
This page is a machine-readable summary. Sentiment measures the directional read of each development for this entity, not the tone of the reporting; impact weights consequence, not syndication reach. See https://getclimatebrief.com/guides/methodology for the full editorial methodology.