Heat dome pushes the Southwest 20°F above normal in early spring
An early heat dome pushed temperatures up to 20°F above normal in California and the Southwest, threatening records in LA and Phoenix.
x(600).jpg?v=1790552292 "Heat dome pushes the Southwest 20°F above normal in early spring"){kind=logo}
Unusual Heat Spreads Across the Western United States
An unusually early heat wave is unfolding across much of the western United States, sending temperatures soaring far above seasonal averages across California and the Desert Southwest.In many areas the air already feels more typical of early summer than mid March. The heat is spreading across a vast region from coastal California into Arizona, NV and the Great Basin.
Meteorologists warn that temperatures will climb sharply during the week. Many locations are expected to experience heat levels rarely observed this early in the year.
Nearly 39 million people across the region are currently under heat alerts as the event continues to expand and intensify.
High Pressure Dome Drives the Heat
The extreme warmth is linked to a persistent dome of high pressure that has settled over the western United States.This atmospheric pattern traps warm air over the region and allows temperatures to rise day after day.
Meteorologists often describe this setup as a heat dome. The high pressure system acts like a lid, preventing cooler air from entering while compressing and warming the air beneath it.
According to the National Weather Service, the heat wave is arriving far earlier than usual.
“Daily record tying or breaking highs will become more common across southern California, the Desert Southwest and into the Great Basin over the next couple of days."
Forecasters indicate that these unusually warm conditions may only be the beginning.
Record Breaking Temperatures Possible in Major Cities
Several major cities could challenge or break monthly temperature records as the heat intensifies.Southern California is expected to experience widespread temperatures above 90°F. In Los Angeles, CA, United States, daily highs are forecast to remain in the mid to upper 90s throughout the week.
Forecasts suggest temperatures could peak near 98°F on Thursday.
In Phoenix, AZ, United States, temperatures are expected to climb into the triple digits by midweek. Forecasts indicate a high of about 105°F on Thursday.
Cities in southern Nevada could see even higher readings. Some areas may approach 107°F later in the week.
Meteorologists note that these values are roughly 20°F or more above normal for mid March.
x(800).jpg?v=1790551110)
Early heat wave: records for LA and PhoenixSeveral cities could approach or surpass monthly temperature records, including:
- San Francisco, CA
- Los Angeles, CA
- Sacramento, CA
- Palm Springs, CA
- Phoenix, AZ
- Tucson, AZ
- Las Vegas, NV
- Salt Lake City, UT
- Albuquerque, NM
- Denver, CO
Heat Dome Could Persist Through the Week
Forecasters say the heat dome responsible for the extreme temperatures may remain in place for several days.The National Weather Service described the system as potentially one of the strongest heat domes observed during this part of the year.
High temperatures may remain elevated well into the upcoming weekend, allowing the heat to persist across large parts of the region.
The prolonged warmth raises concerns for vulnerable groups.
Health officials warn that children, older adults and people with underlying medical conditions may be especially sensitive to the sudden rise in temperatures.
The National Weather Service office in San Diego issued a public reminder urging caution.
“Moderate to major heat risk is expected. Please check on family and friends without air conditioning and avoid outdoor recreation during the afternoon hours this week."
Heat Adds Pressure to Water and Wildfire Concerns
The early season heat arrives during a period when snowpack levels across the western United States are already below average.Meteorologists warn that sustained warmth could accelerate melting in mountain snowfields and worsen an existing snow drought across the region.
Reduced snowpack may have long term impacts on water availability later in the year and could increase wildfire risk during the coming dry season.
Other Extreme Weather Across the United States
While the West experiences intense heat, other regions of the country are facing very different weather hazards.A powerful winter storm is affecting parts of the Upper Midwest and the upper Great Lakes region. Heavy snow is expected across Wisconsin and Michigan.
At the same time, strong winds and tornado threats are possible across several eastern states. Wind alerts extend from the Mississippi Valley toward New England.
Cities including Washington, DC may face damaging winds and severe thunderstorms.
Farther west in the Pacific, a powerful atmospheric river has been affecting Hawaii for several days.
Heavy rain has been falling continuously, triggering widespread flash flooding and landslides across parts of the islands.
News
- Lake Powell Rises 20 Feet as Historic Flooding Boosts Southwest Water Supplies
- Severe Flash Floods Sweep Across Arizona and Colorado, Forcing Evacuations
- Fast-Moving Wildfires Force Evacuations Across Southern California
- Super Typhoon Champi Reaches Category 5 as Tropical Storm Trudy Weakens
- Hurricane Polo Strengthens Off Mexico
- Pacific Hurricanes Draw Attention
- Tropical Storm Lala Batters Hawaii
- Record Arctic Blast Brings Heavy Snow Across the U.S.
- Wisconsin Tornado Leaves Heavy Damage
- Deadly Flooding Hits West Virginia
- Deadly Flooding Paralyzes Texas Hill Country
- Extreme Heat Threatens World Cup Games
- Dangerous Heat Builds for July Fourth
- Dangerous Fire Weather in the West
- Severe Storms and Dangerous Heat Hit U.S
- Gulf Coast Watches Potential Arthur
- Tornadoes Tear Through Illinois and Indiana
- New York Heat Builds Toward 90s
- Scientists Warn New Orleans Could Be Surrounded by Sea This Century
- Storms and Heavy Rain Threaten Memorial Day Plans Across Eastern US
- Dangerous Heat Grips Eastern US Before Storms Bring Sudden Cooldown
- Record Heat Expands Across US
- Severe Storms Threaten Gulf Coast and Southeast
- EF-3 Tornado and Violent Storms Tear Through North Texas
- Violent storms and tornado threat intensify across the Midwest
- Ice slabs crash into Michigan homes as flooding grips lake communities
- Tornadoes and Giant Hail Batter Midwest as Severe Storm Threat Stretches Into Late Week
- Another Kona storm threatens Hawaii with renewed flooding
- Flood watch issued as heavy rain targets South Florida
- Third kona storm in weeks threatens Hawaii with more flooding
- Heavy rain and storms set to soak Central New York through the week
- Severe storms threaten Chicago with hail, tornado risk and sharp temperature drop
- Kona storms devastate Hawaii with historic flooding
- Hawaii faces renewed flood threat as Kona storms return
- Spring Warmup Sweeps Midwest and Northeast Before Another Cool Down
- Early Heat Wave Grips the Western United States
- Massive Storm Brings Tornado Threat and Blizzard Conditions Across the United States
- Deadly Tornadoes Strike Midwest as Supercell Storms Sweep Illinois and Indiana
- Deadly Tornadoes and Giant Hail Strike Central United State
- Another Severe Weather Outbreak Threatens Midwest and Southern United States
- Severe Storms Sweep Central United States With Tornadoes and Large Hail
- Severe Storms Threaten U.S. From Texas to New York This Week
- New York Weather Outlook for March 3 Total Lunar Eclipse
- Bomb Cyclone Blizzard Leaves Northeast Digging Out as Power, Flights, and Roads Struggle
- Historic bomb cyclone buries Northeast under record snow
- Blizzard shuts down the Northeast as travel bans grip New York City
- Avalanche rescue unfolds near Lake Tahoe as winter storm rages
- Storm targets Valentine’s Day weekend across the South and Northeast
- Record snow drought grips the American West
- Strong winds and flooding batter Hawaii as leaders urge residents to stay off roads
- Coldest weekend of winter brings snow and ice
- Arctic blast grips the Northeast with snow and rapid freeze
- Bomb Cyclone Buries the Carolinas Under Historic Snow
- Deep Freeze After Bomb Cyclone Grips Eastern United States
- Deadly Cold Lingers as Another Winter Storm Threatens the U.S. East
- Arctic cold tightens grip as bomb cyclone threat looms along U.S. East Coast
- Deadly Winter Storm Paralyzes Much of the United States
- Historic Winter Storm Threatens Ice, Snow, and Power Outages Across the US
- Dangerous Winter Storm Poised to Grip the Eastern United States
- Wintry Pattern Tightens Its Grip Across the United States
- Cold Air Surges South Across the Southeast
- Snow and Brutal Cold Target the Western Carolinas
- Uncertain Snowstorms Line Up Across the East
- Mild Streak in Chicago Before Winter Returns
- Powerful Winter Storm Paralyzes Travel Across the United States
- Christmas Storm Batters California
- Storms Disrupt Holiday Travel Across the United States
- Holiday Storms Bring Flooding and Snow to California
- Atmospheric Rivers Flood Western Montana Communities
- Levee Breaches Trigger Flood Warnings South of Seattle
- First Measurable Snow Covers New York and the Northeast
- Catastrophic Flooding Threatens Pacific Northwest
- Pacific Northwest Faces Escalating Flood Emergency as New Storms Advance
- Atmospheric Rivers Bring Days of Heavy Rain
- Winter Storm Sweeps West and Midwest as Pacific Northwest Faces Flood Threat
- Winter Divide Across America
- Major Winter Storm Grips Midwest
- Tornado Rips Through Northwest Houston
- Thanksgiving storm threatens major travel disruptions across the U.S.
- Third Storm Drenches Southern California
- Texas Faces Dangerous Flooding as Slow-Moving Storms Dump Heavy Rain
- Polar Vortex Shift Poised to Reshape Thanksgiving Weather Across the Midwest
- Storms Continue Across Southern California
- Atmospheric River Slams Southern California with Flooding and Mudslide Threat
- Arctic Blast Shatters Records Across the Southern US
- Northern lights dazzle U.S. skies amid rare geomagnetic storm
- First Snow of the Season for Midwest and Northeast
- Arctic Blast to Deliver Winter’s First Bite Across the U.S.
- Coldest Air of the Season to Sweep Across U.S. With First Snowfall for Some
- Rain Returns to Seattle After Brief Weekend Sun
- Halloween Weather Split: Rain, Wind, and Chills for Some, Calm Nights for Others
- Stormy End to October: East Coast Faces Coastal Flooding as Melissa Moves Through the Atlantic
- Tornadoes Tear Through Southern Mississippi, Leaving Trail of Destruction
- Wisconsin Winter 2025–2026 Forecasts Show Divided Predictions
- Atmospheric River to Soak the U.S. West Coast Late This Week
- Storm Displaces Dozens in Tempe as Phoenix Dries Out After Days of Rain
- Remnants of Typhoon Halong Ravage Western Alaska
- Nor’easter Pounds East Coast
- Powerful Nor’easter to Batter East Coast With Heavy Rain, Wind, and Coastal Flooding
- Tropical Storm Jerry Strengthens Over the Atlantic
- Hurricane Priscilla Strengthens Off Mexico’s Coast
- Warm days ahead before fall chill returns to Washington, D.C.
- Winter 2025-26: Snowy Season Expected for Central and Eastern U.S
- Dry spell grips central and eastern U.S. as Kentucky heat lingers
- Southwest shifts from monsoon rains to dry, warm October pattern
- Humberto and Imelda Stir Atlantic, Threaten East Coast With Dangerous Surf and Flooding
- Phoenix braces for final monsoon storms of the season
- Central U.S. Faces Severe Storms, Flooding, and Hospital Evacuations
- Hurricane Gabrielle Brings Dangerous Surf to Bermuda and U.S. East Coast
- Central and Eastern U.S. Face Pattern Shift With Rain and Severe Storms
- Chicago Forecast Brings Rain Chances After Summerlike Heat
- Rain and Thunderstorms Moving into Southern California