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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 19h

There is a risk of significant flash flooding in parts of interior SW today as deep tropical moisture associated w/remnants of East Pacific #HurricanePriscilla interacts w/jet streak associated w/an incoming trough. Risk will be highest central/northern AZ and SW UT. #AZwx #UTwx

Excessive precipitation (i.e., flash flood risk) outlook from NOAA's WPC for today (10/6/2025) as visualized on pivotalweather.com. It shows a broad region of slight risk over the interior U.S. Southwest, and a two substantial lobes of moderate risk (i.e., second-highest tier) over northern Arizona and southern Utah, respecitvely.

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Daniel Swain @weatherwest.bsky.social · 17h

More than a few folks sure seem to think that I do, though... 👀

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Daniel Swain @weatherwest.bsky.social · 19h

Next week is looking quite active in CA as a high-amplitude flow pattern develops over North Pacific in downstream response to perturbation of jet stream by West Pacific #TyphoonHalong. NorCal looks quite wet & stormy (rain & iso. tstms/mtn snow); SoCal impacts TBD. #CAwx #CAfire

Snapshot from ECMWF ensemble of an unseasonably deep low pressure system centered just west of San Francisco by early next week. It will likely bring widespread rain, isolated thunderstorms, some mountain snowfall, and possibly some gusty winds though exact path and impacts remain TBD.

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 1d

"Institutions should embrace collective storytelling between those who hold deep knowledge and those with the cultural fluency and media reach to deliver it effectively." Amen to that!

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 1d

"The requirements to succeed on new media platforms are almost precisely the opposite of what successful experts have trained themselves to do: maintain an institutional tone of formal detachment and stay ruthlessly on-message at all times."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 1d

I want to highlight this excellent piece by @noupside.bsky.social and @rachelkleinfeld.bsky.social on the rapidly shifting information & media landscape. Domain experts and the institutions that support them must rapidly change tactics to meet the moment.

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 19h

There is a risk of significant flash flooding in parts of interior SW today as deep tropical moisture associated w/remnants of East Pacific #HurricanePriscilla interacts w/jet streak associated w/an incoming trough. Risk will be highest central/northern AZ and SW UT. #AZwx #UTwx

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Daniel Swain @weatherwest.bsky.social · 1d

Impressive!

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Daniel Swain @weatherwest.bsky.social · 1d

Where is that??

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Daniel Swain @weatherwest.bsky.social · 1d

"Institutions should embrace collective storytelling between those who hold deep knowledge and those with the cultural fluency and media reach to deliver it effectively." Amen to that!

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

"Institutions frequently drop content onto a platform rather than opening a conversation with their audience or understanding what a platform’s algorithm will reward."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

"Audience members are not just consuming—they are contributing. Members of these communities believe information because they are cocreating it."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

"The requirements to succeed on new media platforms are almost precisely the opposite of what successful experts have trained themselves to do: maintain an institutional tone of formal detachment and stay ruthlessly on-message at all times."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

"Public intellectuals and experts who publish only through legacy media outlets are engaging a narrow, affluent, and educated demographic that is increasingly talking to itself."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

"Institutions working on issues that depend on mass public support must adapt to today’s media environment—or risk irrelevance."

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

I'd very strongly encourage public-facing domain experts, practitioners, communicators, and (in particular) those with an institutional leadership role to read this piece it its entirety. But, in keeping with the spirit of its contents, I'm offering some "TL;DR" pull quotes below:

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Daniel Swain @weatherwest.bsky.social · 1d

I found myself nodding vigorously with almost every paragraph based on my own experience as a climate scientist-communicator. I've experienced this rapid and profound shift in the media landscape firsthand, and can confirm that most institutions are woefully behind the curve.

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

1 2 12

Daniel Swain @weatherwest.bsky.social · 1d

I want to highlight this excellent piece by @noupside.bsky.social and @rachelkleinfeld.bsky.social on the rapidly shifting information & media landscape. Domain experts and the institutions that support them must rapidly change tactics to meet the moment.

For Expertise to Matter, Nonpartisan Institutions Need New Communications Strategies

To avoid irrelevance when they are needed most, experts and nonpartisan analysts must rethink not just their channels of communication but also their theory of influence.

carnegieendowment.org

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Daniel Swain @weatherwest.bsky.social · 1d

In case you missed it, this was recorded live (as always) and is available at the link below!

Daniel Swain @weatherwest.bsky.social · 3d

I'll host a livestream on Wed, Oct 8 @ 3pm PT to discuss the likely impacts of weakening #HurricanePriscilla on U.S. Southwest (including southern CA), including who may see some thunderstorms. I'll also a new weather & climate-related federal update...

Weather & climate office hour 10/08/25: Hurricane Priscilla's effects on Southwest & federal update - YouTube

The latest in a recurring series of live, virtual, & interactive "office hours" hosted by Dr. Daniel Swain on various topics related to extreme #weather and...

www.youtube.com

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 2d

New blog post out just before my 3pm PT YouTube livestream! Hurricane Priscilla moisture to bring big rain event to AZ/SE CA later this week, but significant NorCal rain event also possible next week (blame recurving West Pacific typhoon!). #CAwx #CAfire

Hurricane Priscilla remnants to bring widespread Southwest rain/thunderstorms (including far SoCal); more widespread precipitation possible with colder NorCal system by mid-Oct - Weather West

An very mild September across CA, but humidity & some unusual rainfall kept fire risk low September 2025 was yet another "strange" weather month along the Pacific Coast. In California, multiple episodes of precipitation (and a fair bit of thunderstorm activity) brought wetter conditions to much of the state--particularly across central and southern California. Serious,

weatherwest.com

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Daniel Swain @weatherwest.bsky.social · 2d

New blog post out just before my 3pm PT YouTube livestream! Hurricane Priscilla moisture to bring big rain event to AZ/SE CA later this week, but significant NorCal rain event also possible next week (blame recurving West Pacific typhoon!). #CAwx #CAfire

Hurricane Priscilla remnants to bring widespread Southwest rain/thunderstorms (including far SoCal); more widespread precipitation possible with colder NorCal system by mid-Oct - Weather West

An very mild September across CA, but humidity & some unusual rainfall kept fire risk low September 2025 was yet another "strange" weather month along the Pacific Coast. In California, multiple episodes of precipitation (and a fair bit of thunderstorm activity) brought wetter conditions to much of the state--particularly across central and southern California. Serious,

weatherwest.com

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 3d

I'll host a livestream on Wed, Oct 8 @ 3pm PT to discuss the likely impacts of weakening #HurricanePriscilla on U.S. Southwest (including southern CA), including who may see some thunderstorms. I'll also a new weather & climate-related federal update...

Weather & climate office hour 10/08/25: Hurricane Priscilla's effects on Southwest & federal update - YouTube

The latest in a recurring series of live, virtual, & interactive "office hours" hosted by Dr. Daniel Swain on various topics related to extreme #weather and...

www.youtube.com

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 3d

Thunderstorms are potentially possible w/both SoCal remnant moisture & NorCal low (lower odds). These will probably be "wet" storms in all cases, w/little fire risk. Offshore waters remain anomalously warm, which will "juice things up" a bit as well. [3/3] #CAwx #CAfire

NOAA Coral Reef Watch map depicting current ocean surface temperature (SST) anomalies near California. The are almost uniformly positive (warmer than average), as depicted by warm yellow/orange/red colors.

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 3d

While there is still some uncertainty, it now appears that Priscilla's remnant circulation will miss CA to SE but will still bring showers/t-storms to parts of SoCal, esp. south of LA County. Separately, NorCal may see a few showers directly from offshore low. [2/3] #CAwx #CAfire

Map from ECMWF ensemble depicting precipitation over the next 5 days across the American West. Light precipitation is depicted over much of NorCal, mainly north of the SF Bay Area, and light to moderate precipitation is also indicated over far SoCal (mainly south of Los Angeles).

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Reposted by Daniel Swain

Daniel Swain @weatherwest.bsky.social · 3d

After another fairly hot and dry spell across California, cooler and more active weather will once again return later this week as remnant moisture from then-former #HurricanePriscilla interacts with an offshore low pressure system. [1/3] #CAwx #CAfire

Map plot snapshot from ECMWF model depicting the offshore low (NorCal) and the weakening Hurricane Priscilla (west of Baja CA). The field plotted is mid-level moisture (blues represent moister air) and mid-level winds.

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