Weather Underground
Weather Underground is a weather forecasting service built on a network of personal weather stations (more than 400,000 by the company's own count), providing hyperlocal weather data, forecasts, and historical weather information. Originally founded in 1995 as a University of Michigan spinoff, it offers both free ad-supported and premium subscription tiers for weather enthusiasts, developers, and general consumers.
Score generated by AI agents based on publicly cited evidence and reviewed by the project maintainer. Not independently validated. Last assessed 2026-10-01. Score revised 2026-10-01: 55 → 42.
Score History
Timeline events are AI-curated from public reporting. Score trajectory is derived from documented events.
Weather Underground became a commercial company in 1995, spun out of a University of Michigan weather database project led by Jeff Masters, Perry Samson and Alan Steremberg. It offered free internet weather data with modest advertising and no evidence of extractive practices.
The personal weather station network launched in 2001 and turned the site into a crowdsourced hyperlocal service. Jeff Masters' WunderBlog started in 2005 and became a major weather voice, and iOS and Android apps followed in 2011. A free developer API, webcam hosting and member blogs defined an open, community-driven product.
The Weather Channel Companies, owned by NBCUniversal, Blackstone and Bain Capital, bought Weather Underground on July 2, 2012, ending 17 years of independence and folding a rival into the largest consumer weather business. The brand, site and staff were kept separate, a 2014 redesign and a 2015 Storm radar app followed, and the free API and community features stayed intact.
IBM closed its purchase of The Weather Company's product and technology businesses, including Weather Underground, on January 29, 2016, positioning weather data as fuel for Watson's Internet of Things platform; in 2017 the ad business was rebranded IBM Watson Advertising. Member blogs, WUMail and SMS alerts ended in April 2017, the Storm app was dropped for Storm Radar, and a planned webcam shutdown was reversed after backlash. Users in early 2018 called the redesigned site far less useful.
Around May 15, 2018 free API keys were withdrawn without notice; the free API closed on December 31, 2018 and legacy keys stopped on February 15, 2019, breaking many hobby and home-automation projects, though station owners were offered capped free keys. The Los Angeles City Attorney sued the operator of the Weather Channel app over location data in January 2019, co-founder Jeff Masters announced his departure in October 2019, and the December 2019 v6 app sent ratings down. In 2020 CSV exports ended, IBM layoffs closed the Category 6 blog, and the LA suit settled.
Webcam hosting ended on October 21, 2021, removing the last of the old community features, and reviewers described ads taking over pages and covering the radar map. The Hart location-data class action against the Weather Channel app's operator closed in 2023 and a video-privacy suit over weather.com was filed. In August 2023 free ad-free access was limited to stations registered before that month, and IBM agreed to sell The Weather Company to Francisco Partners.
Francisco Partners completed its purchase of The Weather Company, including Weather Underground, at the start of February 2024, and on March 5, 2024 users without an active station lost free ad-free access. A new CEO and CFO arrived in November 2024, an employee review describes repeated layoffs, and a second weather.com video-privacy suit was filed. The product itself has held steady, with strong Play Store ratings and a September 2026 site redesign that added display options while trimming some summaries and widgets.
Alternatives
Weather visualization and forecasting tool that offers multiple forecast model layers including ECMWF and GFS without the ad loading and paywall creep that define Weather Underground's current experience. Windy accepts personal weather station data through its stations service. Easy switch for most forecast uses; some loss of hyperlocal density compared with Wunderground's much larger PWS network.
Community platform built specifically for personal weather station owners. Works with common station hardware (Davis, Ambient Weather, Fine Offset/Ecowitt) and is free to use, with paid plans adding downloadable custom reports. Many weather stations and upload tools can send data to Weathercloud alongside Wunderground, making it a low-cost parallel switch for PWS owners.
Dimensional Breakdown
Summaries below were written by AI agents based on the cited evidence. They are editorial interpretations, not independent research findings.
Dimension History
Timeline (39 events)
Weather Underground Founded as University of Michigan Spinoff
Jeff Masters, Perry Samson, Alan Steremberg, and other University of Michigan colleagues incorporated Weather Underground Inc. as a commercial entity, building on the Telnet-based weather information system Masters had developed in 1991. The site wunderground.com launched offering daily forecasts and hourly conditions for 550 U.S. cities, becoming one of the first commercial internet weather services.
Personal Weather Station Network Launched
Weather Underground began hosting data from personal weather stations, allowing users worldwide to submit their own local weather data. This crowdsourced network would grow to become the platform's most distinctive feature and primary competitive moat; by early 2017 more than 250,000 personal stations were linked to Weather Underground.
Jeff Masters Launches WunderBlog (Later Category 6)
Weather Underground co-founder Jeff Masters launched his WunderBlog, which became one of the internet's most popular weather and climate information sources. The blog exploded in readership during Hurricane Katrina in 2005, establishing Weather Underground as an authoritative voice in extreme weather coverage. It was later renamed Category 6.
Weather Underground Launches iOS and Android Apps
Weather Underground released mobile apps for iOS and Android, bringing its personal weather station data, hyperlocal forecasts and WunderMap radar overlays to smartphones. The Android app eventually accumulated over 5 million downloads with a 4.5-star rating and an Editor's Choice badge before later degradation.
Weather Channel Acquires Weather Underground
The Weather Channel Companies (owned by NBC Universal, Blackstone, and Bain Capital) acquired Weather Underground after 17 years of independence. Deal terms were not disclosed. Weather Underground maintained its separate brand and website, and existing staff were retained, with its San Francisco headquarters becoming a TWCC regional office. The community received the news with apprehension about corporate influence.
Weather Underground Wins $3.5M Cybersquatting Lawsuit
Weather Underground sued Navigation Catalyst Systems Inc., Firstlook Inc. and Connexus Corp. (case filed in 2009 in the Eastern District of Michigan) over 250+ typo domain registrations of its trademarks, after first winning a UDRP over 41 of the domains. In March 2013 it was reported to have obtained a $3.5 million judgment against the defendants.
Weather Underground Launches Major Site Redesign
Weather Underground launched a site-wide redesign with a new 'WU' logo, a more legible typeface, an updated color palette that works better for color-blind users, layouts usable across devices, and a new PWS dashboard. The original design remained available at classic.wunderground.com for users who preferred it.
Weather Underground Launches Storm App for iOS
Weather Underground released Storm, a dedicated iOS radar and storm-tracking app with storm tracks, many map overlays and severe weather alerts, which became popular among weather enthusiasts. The app was later discontinued in favor of The Weather Channel's Storm Radar app, frustrating users who preferred Storm's feature set.
IBM Announces $2 Billion Acquisition of The Weather Company
IBM announced a definitive agreement to acquire The Weather Company's B2B, mobile, and cloud-based properties including Weather Underground, weather.com, and WSI. IBM did not disclose terms; the Wall Street Journal reported a price of over $2 billion. IBM positioned the acquisition as the foundation of its Watson IoT unit and cloud platform. The Weather Channel TV network was excluded from the deal and would license data from IBM.
IBM Closes Weather Company Acquisition
IBM completed its acquisition of The Weather Company's digital properties, including Weather Underground. The Weather Company became part of IBM's Watson and Cloud Platform business unit. David Kenny was named to lead the new Watson platform. IBM gained access to over 5,000 enterprise customers in aviation, energy, and insurance who used Weather Company data.
Weather Underground Ends Member Blogs, WUMail, and SMS Alerts
Weather Underground discontinued member blogs, WUMail email service, SMS weather alerts, NOAA Weather Radio rebroadcast, and aviation features. This mass removal of community features marked the first major wave of stripping under IBM ownership, eliminating services that had defined Weather Underground's community identity for over a decade.
Storm App Discontinued in Favor of Weather Channel's Storm Radar
Weather Underground removed support for its popular Storm iOS app, replacing it with The Weather Channel Interactive's Storm Radar app released in June 2017. Users widely criticized the replacement as inferior to the original Storm app, which had offered more comprehensive data layers and better visualization for weather enthusiasts.
Weather Company Ad Business Rebranded IBM Watson Advertising
At Advertising Week New York, IBM relaunched The Weather Company's advertising business, a portfolio of media, data products such as WEATHERfx and JOURNEYfx, and AI ad tools, as IBM Watson Advertising. A company representative said The Weather Company and its Weather Underground subsidiary were not disappearing; the rebrand separated the ad business from the B2B weather business.
Webcam Hosting Shutdown Announced, Then Reversed After Backlash
Weather Underground emailed users on November 15, 2017 that their user-provided weather webcams would cease to be available on December 15, 2017. After significant user feedback, it announced on December 11, 2017 that it was reversing the decision, but users reported the cameras had been taken down and had to be recreated. The incident foreshadowed the full webcam hosting discontinuation in 2021.
Free API Keys Quietly Removed With No Notice
On or around May 15, 2018, Weather Underground removed the free API key option with no announcement or advance notice to developers. Hobby projects, IoT displays and home automation systems relied on the free tier, and even the tens of thousands of PWS owners who supplied data could not get new keys at the time. Existing free keys kept working for the moment.
Change.org Petition Protests Removal of Free API Keys
A Change.org petition titled 'Wunderground About to Shaft Longtime Weather Station Data Providers' protested Weather Underground's announcement that it would no longer provide free API keys. It said private station owners had bought and maintained hardware at their own expense, some supplying data for 20+ years expecting non-commercial use to remain free, and claimed they would have to pay 'something astronomical like $800.00 a month' for their own data. It gathered 77 supporters.
Weather Underground Free API Fully Shut Down
Weather Underground announced that its legacy API would be retired on December 31, 2018, then extended the retirement date to February 15, 2019. The shutdown broke developer projects and home automation integrations that had built on Weather Underground's data, and developers migrated to alternatives such as OpenWeatherMap. The free API had been a cornerstone of Weather Underground's value proposition to the developer community.
LA City Attorney Sues IBM Over Weather Channel App Location Data Sales
Los Angeles City Attorney Mike Feuer filed a lawsuit against TWC Product and Technology LLC, an IBM subsidiary, alleging the Weather Channel app deceptively collected users' precise geolocation data while telling users it was for 'personalized local weather data, alerts and forecasts.' The suit alleged the data was transmitted to at least a dozen third-party websites for targeted advertising and used to help hedge funds analyze consumer behavior. TWC and its affiliates had developed a location-targeting platform called JOURNEYfx to monetize the data.
LA Lawsuit Says Weather Channel App's Core Business Is Profiting From Location Data
Coverage of the Los Angeles lawsuit reported its claim that, unbeknownst to users, TWC's core business is 'amassing and profiting from user location data', citing a 2016 article that described the company as a 'location data company powered by weather.' A New York Times investigation the previous month had found the Weather Channel was among at least 75 companies receiving precise location data, often shared with advertisers, retailers or hedge funds.
Station Owners Offered Free Replacement API Keys
As the free Weather Underground API closed, personal weather station contributors were offered free replacement API keys covering current PWS observations, a 5-day forecast and station lookup, capped at 1,500 calls a day and 30 a minute. Users later confirmed that anyone sending station data could use the new API for free; developers without a station could not.
Legacy Weather Underground API Keys Shut Off
Weather Underground's API transition team said all legacy API keys would stop working on February 15, 2019 unless otherwise agreed; the old API went fully offline in March 2019. Home Assistant's Weather Underground integration and many other hobby applications broke. Weather Underground continued to issue keys for a new API only to owners of personal weather stations uploading data to the network.
Email Forecast Program Discontinued
Weather Underground announced discontinuation of its Email Forecast Program effective October 1, 2019. Daily email forecasts had been a popular free feature for users who relied on Weather Underground without visiting the ad-heavy website. The removal further reduced the platform's free feature set under IBM ownership.
Co-Founder Jeff Masters Announces Departure
After co-founding Weather Underground 24 years earlier and writing over 3,000 blog posts during a 14-year career at WunderBlog/Category 6, Jeff Masters announced he would leave Weather Underground at the end of October 2019. His departure represented the final severing of the platform's connection to its community-driven roots. Masters subsequently blogged at Scientific American and then Yale Climate Connections.
App v6 Released with Missing Features, Rating Plummets
Weather Underground released app version 6 for Android in December 2019 with a new interface that initially lacked features users relied on, including widgets, notification bar icons, manual tile rearrangement, the reporting station and detailed precipitation data. Recent Play Store reviews turned predominantly 1-star after the app had held a 4.5-star rating. The developer acknowledged in a January 2020 note releasing an app with missing features; most were later restored, but as of April 2020 tile rearrangement had not returned.
Researcher Reports Malvertising on Sister Site Weather.com
A HackerNoon post by a computer-science student reported finding malicious ads (IcePick-3PC/eGobbler malware) served through the AppNexus network on weather.com, Weather Underground's sister site, in about 1 in 1,000 mobile sessions, redirecting users to phishing pages that collected device data. The post highlighted the risks of the ad-heavy model shared across The Weather Company's properties.
CSV Data Export for PWS Data Discontinued
As of March 2020, Weather Underground stopped providing CSV exports of hourly and daily data for its Personal Weather Station Network, eliminating the primary data portability mechanism for PWS owners. Users were left without a straightforward way to export their own contributed historical data, deepening lock-in for the platform's most invested contributors.
IBM Lays Off Dozens at Weather Company, Shutters Category 6 Blog
The Weather Company laid off dozens of employees as part of IBM's broader pandemic-era workforce restructuring. The layoffs were announced internally on May 21 with a last day of June 22. The company simultaneously shuttered the Category 6 blog (formerly WunderBlog), which had run for 15 years as one of the internet's most popular weather information sources. Bob Henson subsequently joined Jeff Masters at Yale Climate Connections.
IBM Settles LA Location Data Lawsuit
IBM and TWC Product and Technology settled the Los Angeles City Attorney's lawsuit over Weather Channel app location data practices. Under the settlement, the company agreed to revise its location-permission prompts to disclose that location data may be shared with partners for ads, and to notify the City Attorney of any changes to those disclosure screens over the next two years. Separately, although the settlement did not require it, IBM agreed to donate $1 million worth of technology to Los Angeles for COVID-19 contact tracing.
Reviewers Report Ads Covering Radar Map and Taking Over Pages
User reviews of wunderground.com complained that 25% or more of the radar map was taken up with ads and that full-screen ads were 'thrown in your face' (October 2021), and later that ads 'take over the entire page, making the website useless' (September 2024). The pattern of ads obstructing core map and page functionality became a recurring complaint.
Webcam Hosting Service Permanently Discontinued
Weather Underground discontinued its webcam hosting service effective October 21, 2021, saying webcam data would be deleted from its servers on or after that date. The company said it wanted to 'better focus on the core products,' but the move eliminated another community feature that had been part of the platform's identity since the early 2000s, and some station owners said they would stop sending data in protest.
Geolocation Class Action Settled After Three Years
The Weather Channel settled its class action lawsuit (Hart v. TWC Product and Technology LLC) alleging fraudulent collection and monetization of geolocation data. The case, filed in 2020, alleged the app tracked users' precise locations at all times and sold data to third-party advertising agencies without adequate disclosure. The settlement terms were not publicly disclosed, and the case was dismissed with prejudice.
VPPA Lawsuit Filed Over Video Viewing Data Sharing
A lawsuit was filed against IBM's Weather Company in federal court in New York, alleging that weather.com shared users' video viewing data and personally identifiable information with third parties mParticle and AppNexus/Xandr (Microsoft) without consent. The complaint cited violations of the Video Privacy Protection Act and the Maryland Wiretapping Act, alleging that video URLs and user names were 'intercepted in real time' by advertising firms.
PWS Ad-Free Grandfathering Cutoff Date Set
Weather Underground established August 2023 as the cutoff date for grandfathered ad-free access for personal weather station contributors. PWS owners who registered before this date and maintained active data uploads would continue receiving ad-free access, while new PWS registrants after August 2023 would not receive this benefit. The two-tier system created unequal treatment among contributors providing identical value to the network.
IBM Agrees to Sell Weather Company to Francisco Partners
IBM agreed to sell The Weather Company's assets, including Weather Underground, weather.com and Storm Radar, to private equity firm Francisco Partners. The sum was undisclosed at announcement; IBM's 10-Q later put it at $1.1 billion inclusive of $250 million of contingent consideration, with about $750 million in cash at closing and a $100 million, 7-year seller-financing loan to the buyer. The price was well below the roughly $2 billion IBM paid in 2016, though IBM expected to book a pre-tax gain on the sale. The sale reflected IBM's narrowing focus on software, cloud and AI.
Francisco Partners Completes Acquisition of The Weather Company
Francisco Partners completed its acquisition of The Weather Company from IBM, including Weather Underground, weather.com, and Storm Radar. The Weather Company began operating as a standalone entity under PE ownership. Rohit Agarwal would later be installed as CEO in November 2024 to guide the company's post-IBM growth strategy. The transaction marked Weather Underground's third ownership change in 12 years.
Ad-Free Access Removed for Non-PWS Users
Weather Underground moved users who did not operate an active personal weather station, and who had been accessing its Ad Free experience at no cost, to a free, ad-supported experience on March 5, 2024, about a month after the Francisco Partners acquisition closed. The company said it was transitioning Ad Free to a paid subscription to fund product investment, and directed users to monthly and annual Ad Free plans.
Fourth Privacy Lawsuit Filed Over Weather Channel Video Data Sharing
IBM was sued again over Weather Channel data sharing, with California plaintiff Ed Penning alleging that watching videos on the Weather Channel website caused his full name, gender, email address, precise geolocation, and video URLs to be shared with mParticle and AppNexus/Xandr without consent. The VPPA lawsuit sought class action certification with potential statutory damages of $2,500 per violation. This represented the fourth major privacy lawsuit against the platform's operators.
Rohit Agarwal Named CEO of The Weather Company
Nine months after the Francisco Partners takeover, The Weather Company named former SoundCloud and CNN product executive Rohit Agarwal CEO and former Mailchimp CFO Michael Love CFO, moving CEO Sheri Bachstein to president of the enterprise business. The release listed the Weather Underground app and wunderground.com among the consumer properties and promised more investment in them.
Redesigned Weather Underground Site Replaces Classic Layout
Weather Underground published a guide to its redesigned website. The new site adds dark mode, a compact mode, a Wundermap time slider, a mini station map on the Today page and Google or magic-link sign-in, but drops the hourly page's Today/Tonight text summaries and quick station switcher, several 10-day sidebar widgets, and two of the five Maps & Radar menu sections. Footer links to the Trust Center, privacy policy and privacy settings were folded into one privacy and ad settings link.
Evidence (47 citations)
D1: User Value Erosion
D2: Business Customer Exploitation
D3: Shareholder Extraction
D4: Lock-in & Switching Costs
D5: Twiddling & Algorithmic Opacity
D6: Dark Patterns
D7: Advertising & Monetization Pressure
D8: Competitive Conduct
D9: Labor & Governance
D10: Regulatory & Legal Posture
Scoring Log (6 entries)
Checked 85 items + prose. 38 verified, 29 corrected (11 date-only), 13 re-sourced, 5 removed. Invented/contradicted: (1) subscription 'cannot be cancelled online' — cited tip-line sighting is about Evens; TWC Terms say WU subs cancel online; (2) WxForum 'ads cover controls' thread is about CWOP sites, not WU; (3) 'location data company powered by the weather' presented as internal self-description — it was a 2016 article quoted in the LA suit (Sophos); (4) '$900M loss'/'$100M deferred' on the IBM sale — 10-Q shows a $100M seller loan and expected pre-tax gain. Also fixed: Sitejabber 1.4/667 -> 2.1/665, PWS API access claim, LA suit defendant, $1M donation not required by settlement, petition date, many evidence dates.
55->42. Since Feb 2026: September 2026 site redesign (dark/compact modes added; hourly text summaries, station switcher, some widgets and map menu sections dropped); Terms of Use updated April 2026 (online cancellation, 30-day annual renewal notice); no new legal actions, price changes or ownership changes found. D1 8->6 (recalibration: core forecast product intact, Play Store 4.7/623K, App Store 3.9/32K; community-feature losses fit 6-7, not 'shadow of former self'); D2 7->5 (correction: station owners kept free 1,500-call/day keys; no current vocal conflict); D3 6->5 (recalibration: PE layoffs and ad-free removal but no documented buybacks/recaps, product still funded); D4 6->4 (recalibration: forecast users have no lock-in; PWS owners multi-upload freely; CSV loss keeps it at 4); D5 4->3 (recalibration: no ranking algorithm, simple pricing; location-data suits concern sibling Weather Channel app); D6 5->3 (correction: 'cannot cancel online' was false; online cancellation documented; remaining patterns are ad obstruction and upgrade nags); D7 7->6 (recalibration: heavy free-tier ads but cheap $9.99/yr ad-free, no ads for payers); D8 4->3 (recalibration: crowded market, no antitrust action, API closure was access withdrawal not competitor suppression); D10 4->3 (recalibration: no lobbying; all privacy suits concern sibling weather.com/Weather Channel app under the shared operator). D9 unchanged at 4. Eras: kept Academic Origins and Community Growth; re-dated TWC Acquisition 2012-07-01->2012-07-02, IBM era 2016-02-01->2016-01-29 and relabeled 'IBM Data Extraction'->'IBM Watson Era', API Kill & Talent Exodus 2019-01-01->2018-05-15 (free API keys withdrawn), Hollowed-Out Platform 2021-01-01->2021-10-21 (webcam hosting ended), current era 2026-02-16->2024-02-01 (Francisco Partners close) and relabeled 'PE Extraction Phase'->'Private Equity Ownership'. All eras re-scored. Note: LA/Hart/VPPA cases name The Weather Channel app or weather.com, not Weather Underground; kept as shared-operator context and weighted accordingly. Category 'Weather' looks right.
Triaged 2026-06-30 (Wave A); no rescore warranted (no material change / changes sub-threshold / flag refuted on verification).