Chad Thackeray

In a new report, we (@peedublya @ProfAlexHall @GavinDayanga) explore the weather and climate factors that allowed the Los Angeles fires to become so large and destructive. @UCLA @UCLAIoES @UCLASustainLA Full report: sustainablela.ucla.edu/2025lawildfires Summary: ioes.ucla.edu/article/climat…

Strongest El Niño on record this year?! New ECMWF guidance shows a *75% chance of a super El Niño* by October, with some scenarios suggesting the most intense event in more than a century. It will bring wide-reaching weather impacts that last into 2027 🧵

March 2026 will probably become the warmest March on record for the United States and the *warmest month compared to average* overall, pending final data. It was a remarkable 7 degrees above-average across the country as a whole.

Most of the snow in California’s Sierra Nevada has melted after a record-breaking heat wave. “Climate change is influencing California’s water system quickly and severely.” latimes.com/environment/st…

🌡️Every single weather station we have recorded the warmest March on record. Most would have been the warmest April too. More sites below🧵

Here’s another way of looking at March 2026 from climatologist Brian Brettschneider. The dark red is where the region experienced its warmest March on record. A big portion of the West concurrent with the extreme #heatwave Much of that area was 12-16°F above normal!!

March 2026 finished with an average temperature of 73.0°F here in Las Vegas. Not only does this demolish the old March record of 66.7°F (2015), it is also warmer than any April on record here... #nvwx #VegasWeather

As the first reanalysis data become available, I think I can say with a fairly high degree of confidence that the March 2026 heatwave will go down as the most anomalously extreme heat event ever observed at any time of year in the southwestern U.S.

Never seen anything like this. 200+ monthly records set today alone! Every pink dot means a city set its new all-time highest March temperature! That’s around 570 new monthly records in the last 4 days. Some set multiple times. By far the most rogue #heatwave the US has experienced in memory.

At this hour, every station in Arizona and Nevada is recording a new *ALL-TIME* monthly record highs. Numerous other states have a majority of stations also recording new all-time high temperatures. Historic is, in my opinion, an understatement.

It was a record kind of day today. This is just the start of a LONG DURATION HEAT WAVE, with no relief expected the rest of the week - especially inland of the beaches. Take heat risks seriously. Make a plan now on how you will stay cool the rest of the week. #cawx

Today, the Trump administration repealed the endangerment finding: the ruling that served as the basis for limits on tailpipe emissions and power plant rules. Without it, we’ll be less safe, less healthy and less able to fight climate change — all so the fossil fuel industry can make even more money.

WSJ: In the biggest rollback of climate policy yet, the Trump administration will repeal the finding that greenhouse-gas emissions endanger public health wsj.com/politics/polic…

Breaking News: The EPA will stop considering lives saved when setting pollution limits and instead calculate only the cost to businesses. nyti.ms/45RcBNE

Breaking News: President Trump said the U.S. would withdraw from the U.N.’s bedrock climate treaty, and 65 other treaties and agreements. nyti.ms/45J853H

Strong northerly winds will develop tonight, transitioning into a Santa Ana wind event Fri into at least Sat. High Wind Warnings and Wind Advisories have been issued. There is a HIGH risk for downed trees and power outages due to softened soils from recent soaking rains. #CAwx

Here are some impressive 14 day rainfall totals across Southwest California! The transverse ranges across Los Angeles, Ventura, and Santa Barbara co. are the winners here. Data courtesy of @VCPublicWorks. Disclaimer: Some points (i.e Morro Bay) may be inaccurate. #CAwx #LARain

A rare High Risk has been issued: "The potential for high hourly rainfall totals will accentuate runoff over soil that is relatively dry and or over recent burn scar areas. This will pose a significant threat of flash flooding, landslides, rock falls and mud slides. The greater than normal travel during the Christmas Holiday will likely expose a potentially larger number of people to these life threatening hazards." @NWSWPC Discussion

Exclusive: The Trump administration is moving to dismantle the National Center for Atmospheric Research in Colorado, according to a senior White House official, taking aim at one of the world's leading climate research labs. usatoday.com/story/news/pol…

An unusually strong storm system will bring widespread rain to southern California through Sunday. The period of most concern is tonight through Saturday night when a large area of heavy rain and isolated but potentially severe thunderstorms will bring a moderate to high risk of significant flash flooding, debris flows, and damaging winds. There has been some uncertainty as to where the plume of heaviest rain Friday night will set up, but the latest suite of guidance suggests that plume will be right over Los Angeles and points immediately west, including the hard hit areas from last year's wildfires around Malibu and the Palisades. Timing will be everything as to how widespread the impacts will be. However, given the plume's near worst- case- scenario position from Malibu and the highly urbanized L.A. Basin, and the unusual amounts of both moisture available and instability for November, it's very possible that the heavy rain over burn scars and urbanized areas could quickly worsen flash flooding leading to Moderate level impacts late Friday night and into Saturday. WHAT YOU CAN DO: Avoid the roads, stay indoors as much as possible, stay aware of your environment and keep up to date with the latest forecast at weather.gov.

#SantaAnaWinds are bringing critical #FireWeather to portions of LA/Ventura Counties through Wed. Gusty winds, very low humidity will make extreme fire behavior likely with new fire starts. Use extreme caution with anything that can spark a wildfire. #CAwx