(CNN) — An unusually long and far-reaching communications outage hobbled the National Weather Service just as deadly severe thunderstorms were tearing across the Midwest and Ohio Valley on Tuesday evening.
The outage is more evidence of the long-running IT infrastructure challenges facing the agency, which is part of the National Oceanic and Atmospheric Administration.
The outage meant that severe thunderstorm, flash flood and tornado warnings were significantly delayed in reaching the public, except via NOAA Weather Radio, according to the NWS.
According to a person familiar with the matter, the root cause of the issue, which lasted from 6 p.m. ET to 7:14 p.m. ET, was a software upgrade being made to the main computer system that forecasters use to monitor weather conditions and issue watches and warnings, known as AWIPS.
This software system is antiquated, and the NWS is working to update and replace it with a new cloud-based architecture by 2028, the person said. They were granted anonymity because they were not authorized to discuss the issue.
Forecasters at several local forecast offices in multiple states that were impacted by destructive storms — including Kentucky, Indiana and Ohio — were left scrambling to try to get their warnings out via media outlets, social media platforms and other means once meteorologists became aware that warnings they were sending out via AWIPS were not being received in a timely manner.
In a post on X, the NWS forecast office in Jackson, Kentucky, wrote at 6:06 p.m. ET: “***This is urgent*** . We are having issues with our warnings getting out to everyone. If you are in Hazard, Jackson, Pikeville, and Whitesburg, PLEASE SEEK SHELTER NOW. This is a dangerous line of storms!”
In some cases, warnings were delayed as long as 20 minutes or more between the time of issuance and when they showed up on weather apps, in TV stations’ graphic systems, and via text and wireless alerts, among other means.
The average national lead time for a tornado warning is just 13 minutes between the warning being issued and a tornado touching down or moving into a warned area.
Communications outages at the NWS have been a consistent challenge due to the age of its telecommunications infrastructure. However, the trouble on Tuesday evening stands out for being unusually long-lasting and large in scope, affecting offices nationwide.
“All NWS offices are currently issuing forecasts and warning products normally and without delay,” said National Weather Service spokesperson John Ewald in a statement to CNN on Tuesday night.
“Between (6 p.m. and 7:14 p.m. ET) today, an internal software issue caused a delay in products being issued publicly. Warnings reached NOAA Weather Radio, but all other dissemination paths were impacted,” he said. “We will continue to investigate the root cause of the delays to prevent the issue from reoccurring. As always, NWS advises everyone to have multiple ways of receiving critical, time-sensitive warnings.”
The NWS is currently staffing back up after DOGE-related cuts to its workforce last year, though it is not expected to return to pre-Trump administration levels. Many of the most experienced forecasters and technicians left the agency during the past year due to incentive programs offered for veteran employees to leave public service.
This was part of the Trump administration’s effort to shrink the size of the federal government.
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