One of the routine pieces of equipment that forecasters at the Tucson office of the National Weather Service have relied on for decades has been sidelined: weather balloon launches have been paused since late January while staff rework their helium delivery and storage system. The interruption does not stem from a lack of demand for the data the balloons provide, but from practical changes in how the lighter-than-air gas arrives and is handled on site.
National Weather Service staffer holds a weather balloon prior to release — launches that have been paused at Tucson’s office amid helium supply issues.
The helium-filled balloons are not used as novelties; they are workhorse tools that lift instrument packages high into the atmosphere and return measurements that feed local forecasts. Among the key pieces of information those launches provide is moisture content aloft — a measurement that can be crucial when forecasters are trying to distinguish the threat posed by heavy rainfall from other hazards. “If we know what the precipitable water is, which is a measure of the water in a column of air, for example. We can use that information to say that today is more of a flash flooding threat as opposed to a wind threat,” the office lead explained, summarizing why the observational soundings matter for decisions about monsoon and other severe-weather threats.
The pause in Tucson’s launches is a supply-chain and logistics story rather than a technological failure. Helium itself is a finite resource on Earth — abundant in space but not something that can be manufactured from other materials — and global disruptions to production and shipment have been reported elsewhere. That said, the local problem that forced the halt in ballooning was not tied to those broader international dynamics, according to the office lead. Instead, a change in how the supplier delivers helium tanks forced the Tucson office to halt launches while new storage capacity and plumbing were installed.
Previously, Tucson received helium in heavy cylinders, some weighing roughly 130 to 140 pounds apiece. Those large tanks are awkward and require special handling. The supplier shifted to smaller cylinders because the larger units were difficult to manage safely. Converting to the new containers has not been a simple swap; staff have had to design and install different storage arrangements and alter the piping that carries gas up to the roof-based launch area. Those modifications have taken time, and until the new system is completed the office has stopped sending balloons aloft.
A technician prepares a weather balloon and its parachute inside a garage, equipment used to collect upper‑air moisture data for forecasts.
The grounded period has not left the forecasters without options for maintaining accurate forecasts. The Tucson office can supplement observations with balloon launches conducted by neighboring forecast offices, including the one in Phoenix, and with model-derived soundings produced by numerical weather prediction systems. “So we do have model soundings that come from numerical weather prediction models that we can use to simulate what's happening that are very similar to actual observations. It's not going to be a perfect one-for-one match of what we would get from an observational balloon launch, but it does get us to the point where we can see what's going on in the atmosphere,” the lead said, underscoring that the alternative sources provide usable situational awareness even if they are not an exact substitute for on-site measurements.
Operationally, the office is balancing the temporary limitations with the broader mission of keeping forecasts as reliable as possible. The observational balloons, when flown, provide a local check on the vertical profile of temperature, humidity and winds — data points that sharpen day-to-day messaging about threats such as flash flooding during active monsoon periods. In their absence, forecasters are relying more heavily on numerical model output and regional observational networks until the local helium infrastructure is restored.
The good news, the office lead said, is that the pause is expected to be short-lived. The new storage facilities and rooftop piping are nearing readiness, and once the revised helium system is fully installed the office plans to return to its routine of launching balloons twice daily. Those twice-daily observational soundings will resume because the extra, localized data they deliver plays a distinct role in refining forecasts and threat assessments.
For now, the Tucson team continues to monitor the sky with the tools it can access and to prepare the launch operations for a prompt resumption. The grounding since late January has been a temporary operational hurdle born of a supplier change in cylinder size and the necessary adjustments to safely handle and deliver the gas to the roof launch site. When the new tanks are integrated into the office’s supply chain and the plumbing is completed, staff say they will reinstate the twice-daily flights that have long been part of the office’s forecasting routine.
NOAA issued a firm fixed‑price purchase order to Green Lantern LLC to supply helium to the Tucson Weather Forecast Office covering Oct. 1, 2024 through July 31, 2025 for up to 44,720 cubic feet of gas, with a contract value listed at $51,473.18.
The Tucson forecast office is colocated at the edge of the University of Arizona campus and has historically conducted its twice‑daily balloon releases from a rooftop launch area on that campus.
Other NWS offices have faced similar disruptions: for example, the Boulder/Denver area suspended launches amid helium shortages while relying on aircraft and nearby launch sites for soundings, and the Albany office previously paused launches while new helium piping and an inflation facility were completed.