Daniel Swain

Should be back up now.

No, the site is down for unknown reasons (i.e., it's not just you). Working to fix it, but the timing is pretty terrible given other obligations! It has become increasingly difficult to operate a highly-trafficked website on a shoestring budget in 2026, that is for sure. 👀

In case you missed it, the recording is now available via the same link below.

A record warm winter in the Western U.S. : What does it mean for snowpack, water supply, & wildfire? - YouTube The latest in a recurring series of live, virtual, & interactive #weather and #climate-focused "office hours" hosted by Dr. Daniel Swain. 3/2/2026 topic: I'l...

I'll host a short-notice livestream later this afternoon (Mon, 3/2, at 2pm PT) to discuss recent news that winter 2025-2026 was the warmest on record--by far--across the Western United States. I'll discuss snowpack, water supply, and wildfire implications.

Lake Powell is nearing a level where Glen Canyon Dam can’t generate power.
Federal officials are considering unprecedented cuts to water releases to keep turbines running — with ripple effects for ecosystems, water users, and the Colorado River Basin.

Read the story: buff.ly/LAE9KAx

There is a remarkable amount of "both sides"-ing regarding temperature these days--reflected in more than a few misleading U.S. temperature anomaly maps by major outlets regarding this past winter (i.e., the non-historic Eastern cold gets much brighter colors than the record-shattering warm West). 👀

December 2025 through February 2026 was the 2nd warmest winter on record for the Contiguous U.S. according to Prism climate data. The widespread record to near record warmth in the west easily outweighed the cool temps in the east. 🔥🔥🔥

A record warm winter in the Western U.S. : What does it mean for snowpack, water supply, & wildfire? - YouTube The latest in a recurring series of live, virtual, & interactive #weather and #climate-focused "office hours" hosted by Dr. Daniel Swain. 3/2/2026 topic: I'l...

I'll host a short-notice livestream later this afternoon (Mon, 3/2, at 2pm PT) to discuss recent news that winter 2025-2026 was the warmest on record--by far--across the Western United States. I'll discuss snowpack, water supply, and wildfire implications.

Following as well. I'm no MD or physiologist, but structurally the argument made therein seems off, and the actual analysis quite minimal, so I'd be eager for someone more qualified to opine.

Congress has appropriated the funds to NSF but OMB is delaying the release. When funds are released, NSF, which has lost almost 1/5 of its staff, will struggle to evaluate proposals. Since they have to award the funds, big projects with established PIs will benefit. This is how US science dies.

Trump Is Attacking Climate Science. Scientists Are Fighting Back. It’s easy, looking at the past year, to see the damage the administration has done. But researchers are also stepping up, trying to fill the gaps.

One year in the federal assault on climate science — a review and prospective

As ever, this example illustrates just how important both weather & climate conditions actually are. It has been exceptionally dry & warm, but today's winds were light--allowing an ignition in a potentially very risky spot relative to Boulder to remain easily managed/largely inconsequential.

But this is a great example of a location that would benefit greatly from more extensive prescribed fire under less adverse burning conditions. As in CA, there are practical challenges in implementation (both real and perceived), but the benefits would be substantial!

Main challenge here is that Front Range is experiencing an increasingly severe drought during what has been the warmest winter on record, w/frequent high wind events during downslope conditions. We are fortunate today's fire did not occur on a much windier day, which have been frequent recently!

Under the specific conditions it was burning today, where this burn stayed mainly in understory with occasional torching, that's likely true! (Although the native conifers don't always do so well when they burn amid severe drought during winter dormancy, as with similar winter fires in recent yrs).

Surface fire, as in "fire burning surface fuels" as opposed to getting up into the tree canopy. This fire is now well managed, BTW.

And record-breaking daily-to-monthly high temperatures are occurring, in even more widespread fashion, yet again today. #CAwx #AZwx #NMwx #COwx

Photograph showing current fire conditions.

#BlueBellFire in #Boulder, CO (near Chautauqua Park) currently burning amid extremely dry and near record-warm conditions (69F and 7% RH). Lack of strong winds right now thankfully a major mitigating factor. So far, mostly sfc fire plus occasional torching in confers. #COwx

I am officially issuing a "cool cloud watch" for NorCal! The offshore low has entrained subtropical moisture; in addition to bizarrely muggy airmass, this will contribute considerable instability & subsequently to widespread convective clouds & some thunderstorms this PM. #CAwx

Air aloft won't be too cold, so hail will actually be less likely than usual with any thunderstorms that pop up this weekend. But hail can still happen in almost any stronger thunderstorm, so you could still get lucky.

Fog in the 60s in Feb in Central Valley really is striking.

Map showing predicted convective available potential energy (CAPE), a measure of atmospheric instability related to thunderstorm risk, over California from the ECMWF model. Values as high as 1000 J/kg are indicated, which is significant by CA standards.

Scattered showers & thunderstorms will likely occur in this remarkably warm/humid/conditionally unstable airmass this wknd across NorCal. Best odds in Sierra, northern foothills, and northern Sac Valley. But isolated showers/t-storms possible as far south as SF/Sac as well! #CAwx

Map showing predicted dewpoint, a measure of absolute humidity and "mugginess," over California from the ECMWF model. Values as high as 65F are indicated over the Central Valley, which is significant by CA standards.

Map showing predicted afternoon temperatures on Saturday over California from the ECMWF model. Values are well above average, and spring or summer-like in many places.

In fact, this may be one of the most conspicuously humid airmasses in recent memory across the Sacramento & San Joaquin Valley--with air temperatures in the 70s and dewpoints into the mid 60s! 70s are not record-breaking, but mid-60s dewpoints are remarkable for Feb. #CAwx

Map showing the relative anomalousness of precipitable water, a measure of the total amount of water vapor in the atmosphere, over California on Saturday from the ECMWF model. Values are anomalously high statewide.

In addition, a weak cut-off low will entrain copious subtropical moisture (remnants from last week's atmospheric river) over NE Pacific & drag it inland across NorCal Sat and Sun. This will bring an extremely warm/muggy winter airmass--and along with it some thunderstorms! #CAwx

Map depicting predicted departures from average of temperatures later on Friday across the U.S. Southwest from the ECMWF model. Highly anomalously warm values are depicted nearly everywhere.

Map from NOAA NWS depicting specific locations expected to approach or exceed high temperatures today. Many such locations are noted in southern CA, AZ, NV, and adjacent regions.

Exceptionally warm-to-hot late winter conditions expected across the Southwest through the weekend, peaking Fri and Sat. Numerous daily record highs (and record warm overnight minimums) will be set, along with some Feb monthly records possible. [Thread] #CAwx #AZwx #NVwx

Map from coolwx.com depicting locations currently experiencing record-breaking temperatures. Numerous locations in the West are experiencing record high temperatures, with some locations breaking all-time February monthly records. No locations are experiencing record low temperatures.

Remarkable and widespread record warmth today across the Southwest. In fact, some locations in southern CA and southern AZ are not just breaking daily records, but also monthly February records--with current temperatures well into 90s and approaching 100F in some spots. #CAwx #AZwx

There has been an amazing outpouring of support for the National Center for Atmospheric Research (NCAR) amid its proposed dismantling from people, institutions, & companies all across the country. You, too, can help by sending feedback to NSF by Mar 13th: www.ametsoc.org/ams/...

Map showing predicted convective available potential energy (CAPE), a measure of atmospheric instability related to thunderstorm risk, over California from the ECMWF model. Values as high as 1000 J/kg are indicated, which is significant by CA standards.

Scattered showers & thunderstorms will likely occur in this remarkably warm/humid/conditionally unstable airmass this wknd across NorCal. Best odds in Sierra, northern foothills, and northern Sac Valley. But isolated showers/t-storms possible as far south as SF/Sac as well! #CAwx

Map showing predicted dewpoint, a measure of absolute humidity and "mugginess," over California from the ECMWF model. Values as high as 65F are indicated over the Central Valley, which is significant by CA standards.

Map showing predicted afternoon temperatures on Saturday over California from the ECMWF model. Values are well above average, and spring or summer-like in many places.

In fact, this may be one of the most conspicuously humid airmasses in recent memory across the Sacramento & San Joaquin Valley--with air temperatures in the 70s and dewpoints into the mid 60s! 70s are not record-breaking, but mid-60s dewpoints are remarkable for Feb. #CAwx

Map showing the relative anomalousness of precipitable water, a measure of the total amount of water vapor in the atmosphere, over California on Saturday from the ECMWF model. Values are anomalously high statewide.

In addition, a weak cut-off low will entrain copious subtropical moisture (remnants from last week's atmospheric river) over NE Pacific & drag it inland across NorCal Sat and Sun. This will bring an extremely warm/muggy winter airmass--and along with it some thunderstorms! #CAwx