Radar Alone Isn’t Early Enough

Traditional rainfall radar detects a storm once it’s already dense enough to reflect a strong signal, which is often later than operators would like. Selerys’s SKYDETECT closes part of that gap on its own: a short-range X-Band radar with a 6kW antenna, covering a 30km radius in full half-sphere monitoring, built on a storm database spanning 20 years of pattern data. It distinguishes a genuinely developing storm from clouds just passing through, and it installs on a tower, mast, or building in a single day, with mobile mast-mounted units available for temporary or urgent coverage.

But radar still has a physical limit: it needs enough precipitation density to get a clear return. Electrical activity inside a cloud builds before that density arrives.

Reading the Storm Before the Radar Can

That’s the gap EVEARLYS is built to close. It’s a UHF interferometric lightning detector, physically four panels per installation, each 1.3m by 1m and 7kg, giving 180° of field of view per panel, running on as little as four hours of uninterrupted power. It detects more than 99% of total lightning activity, both intra-cloud and cloud-to-ground, at a processing resolution of 10 microseconds.

The value isn’t that EVEARLYS replaces SKYDETECT. It’s that the two read different signals from the same storm. SKYDETECT sees the storm’s shape and movement on radar. EVEARLYS reads how electrically active it already is, which tells operators how mature a cell that’s already visible on radar actually is, before it’s dense enough to register strongly on traditional rainfall radar. Used together, they turn “a storm is forming” into “this specific cell is far enough along that it needs a response now,” which is the distinction that actually matters inside a 10-minute window.

Turning a Warning Into a Launch

Detection only helps if it turns into action fast enough to matter, which is where CIRRUS, Selerys’s coordination software, does its work. It centralizes SKYDETECT, EVEARLYS, and the SOBLI balloon and drone fleet in a single interface, scanning the half-sphere in HD once a minute and tracking cloud cells in real time. It anticipates cloud motion 10 to 20 minutes ahead, using the same storm database that powers SKYDETECT, and issues automated alerts by SMS, email, or phone the moment a cell crosses the threshold that warrants a response.

From there, a launch decision through a SOBLI station reaches its target in under five minutes, well inside the 10-minute window a storm cell actually allows. Every launch and every reading gets logged to a searchable archive going back more than a year, along with flare and launch stock levels per station, so an operator isn’t just reacting in the moment. They’re building a record of exactly which cells got treated, when, and with what result.

What Faster Detection Is Actually Worth

The wine-region hail mitigation results Selerys has published elsewhere, a 74% drop in severe hail frequency and a 26% reduction in average hailstone size, don’t come from the balloons alone. They depend on the balloons arriving inside a window that’s often shorter than the time it takes to make a phone call. Detection speed is what makes that window usable at all. A launch system that can reach a target in five minutes is only as good as the warning that tells it when to fire, and that’s the part of the chain that early warning technology is actually solving.

The Broader Pattern

Hail isn’t becoming less frequent. National data across France, for instance, shows a rising trend in hail days over the past two decades, even in regions with active mitigation programs holding their own local numbers flat. That divergence, worse conditions regionally, stable or improving outcomes locally, is what early warning paired with fast-response seeding is built to produce: not a world without storms, but a shorter list of storms that actually get to do damage.

The post Why Hail Damage Comes Down to Minutes, and How Early Warning Changes the Outcome appeared first on Selerys.

The Aircraft Problem

A manned aircraft is the most flexible tool on paper. It can fly to any target within range and needs no ground infrastructure beyond an airport and an operations center. In practice, that flexibility comes wrapped in delay. Getting a crew airborne from immediate readiness takes around 30 minutes just to take off, and 50 to 70 minutes before the aircraft is actually on target. From telephone readiness, the numbers stretch further: 75 minutes to take off, 95 to 120 minutes to reach the storm. Against a cell that’s finished its life cycle in 20 minutes, that math rarely works out in the aircraft’s favor.

Civil aviation rules add a second constraint: two manned aircraft can’t work the same storm cell simultaneously, so a plane treats one target at a time, in sequence, while a broader weather system may be producing several cells at once. Add the need for a licensed pilot, flight clearance before every sortie, and operations that mostly stop at sunset for safety, and an aircraft ends up best suited to isolated, well-forecast, daytime events rather than the fast-moving or nocturnal storms that cause the most damage.

Where Drones Fit

A drone closes some of that gap. It needs no pilot inside the aircraft and can be dispatched faster than a manned sortie. Selerys runs cloud seeding drones across fixed-wing, rotary-wing, VTOL, and multicopter platforms, chosen by mission type and local constraints like terrain and available landing space. A rotary-wing platform hovers at an optimal seeding speed of 5 m/s and holds steady in wind up to 15 m/s, giving it precision an aircraft can’t match at low altitude.

What actually differentiates Selerys’s drone operation isn’t the airframe. It’s the mission manager, run through Selerys’s CIRRUS software, which takes remote control of whichever platform is deployed and reacts to changing conditions in flight. Reaction time from decision to seeding runs under 15 minutes. The tradeoff: a drone still requires a certified operator, flight authorization, and continuous in-flight supervision, plus regular battery maintenance, since a drone’s power source is a lithium battery pack that needs replacing every few months.

Why Balloons Win on Speed and Reach

LAICO, Selerys’s smart balloon system, sidesteps most of what slows the other two down. A balloon launches from a solar-powered SOBLI ground station by remote command, no technician required on-site, and reaches its target in under five minutes from the decision to launch. Because the balloon’s flight authorization is granted once rather than per flight, and because its light weight places it in the lightest free-balloon category under international flight regulations, there’s no clearance to wait on and no daily readiness call to make.

The balloon also isn’t limited to one target. A SOBLI network of launch stations can seed multiple storm cells across a wide territory in the same window, something neither an aircraft (one cell at a time, by regulation) nor a single drone (one moving target per mission) can do. Each station keeps up to 24 balloons pre-loaded and can release up to 6 at once, so a station can respond through an entire storm event without needing to reload mid-storm.

Conditions that ground a plane or a drone, icing, severe turbulence, full darkness, mountainous terrain, don’t stop a balloon. It climbs on updrafts rather than fighting them, which means it keeps working through exactly the weather that makes the other two platforms stand down. And because seeding at speeds above roughly 60 m/s (aircraft-typical speeds) breaks the seeding agent’s particles down too small to be effective, the balloon’s slower ascent, close to the 5 m/s an independent German study found optimal, actually works in its favor rather than against it.

In flight, each balloon also does double duty as a sensor: it streams live GPS position and radiosounding data, temperature, humidity, pressure, back to CIRRUS, building a full vertical profile of the cloud in a single ascent. An aircraft needs multiple passes at different altitudes to assemble the same picture.

So Which One Actually Gets Used

Selerys doesn’t run one platform to the exclusion of the others. Drones earn their place on a moving or precisely defined target where a balloon’s launch-station network isn’t the right fit. Balloons carry the bulk of fixed-site and territory-wide operations, hail mitigation over a vineyard season after season, rain enhancement across a farming region, because their combination of speed, autonomy, and all-weather reliability matches what those missions actually need. The deciding factor is rarely which platform is more advanced in the abstract. It’s which one can still be airborne and on target once the storm cell’s ten-minute window opens.

The post Balloons, Drones, or Aircraft: How Selerys Picks the Right Tool for Cloud Seeding appeared first on Selerys.

Setting Up a Study That Could Withstand Scrutiny

In 2021, the region’s wine council deployed Selerys’s LAICO SOBLI system: SKYDETECT radar coupled with smart balloons carrying hygroscopic salt. Rather than comparing a handful of storms before and after, the evaluation ran three separate analyses across 2016–2025 and required all three to agree before drawing a conclusion:

• A before/after comparison inside the treated zone
• A difference-in-differences comparison against a nearby untreated control zone within 15km
• An event-by-event review, cross-checking hail reports against radar storm tracks and actual balloon launch records

Hail was measured against two thresholds: 1.5cm and above, the point where agronomic damage starts, and 1.9cm and above, where crop losses become close to systematic.

The Results

Across all recorded hail events, mean hailstone size fell from 1.66cm before 2021 to 1.23cm after, a 26% decrease. The events also became more consistent: the standard deviation in size dropped from 0.67 to 0.29, meaning fewer of the outsized hailstones that do the most damage.

The result held up under statistical testing at a level rarely seen in field studies (p < 0.0000001), which rules out the possibility that the treated zone just had a run of lucky years.

For severe hail specifically, at or above 1.9cm, the treated zone saw an 11% reduction in mean size while the untreated control zone saw a 16% increase over the same period, a 27 percentage point gap between the two. Annual frequency of large hail events in the treated zone dropped 74.3%, from an average of 3.89 events a year down to 1.00. The control zone, over the same stretch, rose 4.7%, putting the gap between the two zones at roughly 79 percentage points.

In real operational conditions, 2023–2024 launch records showed better than a 90% success rate overall, rising to 95% for the largest hailstorms when balloons launched ahead of the storm’s arrival rather than reacting to it.

Ruling Out the Obvious Objection

The first question anyone asks about a result like this: did the storms just start missing the vineyards? The event-by-event analysis answers that directly. Radar tracks confirmed the same storms that produced the reduced hail did in fact cross the treated zone. They weren’t deflected or diverted around it. The reduction came from the balloons intercepting the storm’s hail-forming process, not from the region getting lucky with storm paths.

That distinction matters, because national hail data for the same period shows the opposite trend almost everywhere else. Hail days at the 1.5cm threshold rose nationally across France over 2006–2024, while the treated zone held a limited, largely flat exposure through the same window, a pattern consistent with active mitigation working against a worsening regional baseline rather than a naturally quiet decade.

How the Balloon Network Gets There in Time

Hail forms fast. A storm cell’s working life is roughly 20 minutes, and the real window to intervene before hail actually forms is closer to 10. SKYDETECT radar, monitoring a 30km radius, flags a developing storm cell early enough for the SOBLI network to respond within that window: Selerys’s balloon systems reach their target in under five minutes from the decision to launch, without a technician needed on-site and without the flight authorization delays that ground or slow other seeding methods.

A single launch station stays fixed at the same location season after season, which fits a vineyard’s needs better than a mobile or aircraft-based system: the same protection returns every year without redeploying infrastructure.

What It Adds Up To

Nine years of data, three independent analytical approaches, and one consistent conclusion: 74% fewer severe hail events, smaller and more uniform hailstones when hail did occur, and a better than 90% operational success rate under real storm conditions. For an industry where a single storm can determine a vintage, that’s the kind of evidence that moves a technology from promising to standard practice.

The post Case Study: Cutting Severe Hail Frequency by 74% in a European Wine Region appeared first on Selerys.

A National-Scale Trial, Not a Pilot

In November and December 2022, Romania ran a nationwide test of automated balloon seeding, supported by the Romanian National Agency for Hail Suppression and Precipitation Enhancement (AASNACP), under the Ministry of Agriculture. The agency didn’t just sign off on the trial. It ran the radar monitoring and the statistical analysis itself, which is what makes the result worth taking seriously: the data wasn’t self-reported by Selerys.

The technology behind it was Selerys’s LAICO balloon system, launched from SOBLI (Self-Operating Balloon Launcher Instrument) ground stations. Each station is solar-powered, remotely commanded, and can move from a launch decision to seeding in under five minutes.

The Numbers

Across seven active seeding days, rainfall consistently landed well above what the same storm systems would have produced untreated:

That works out to a 300–500% increase in rainfall compared to baseline, with more than 90% operational success across a range of atmospheric conditions. Seeding effects showed up within 10 minutes of a launch and held for 30 to 60 minutes afterward, long enough for radar and soil-moisture readings to confirm the boost reached the ground rather than evaporating on the way down.

Why the Balloon Made the Difference

A storm cell is short-lived. A single cell runs through its life cycle in about 20 minutes, and the real window to treat it, the point where seeding actually changes the outcome, is closer to 10. An aircraft has to be airborne and on target before that window closes, and aviation rules only allow one manned aircraft per storm cell at a time. If a storm throws up three cells at once, a plane treats them one after another, if it can reach them at all in time.

A LAICO network doesn’t run into that limit. Several SOBLI stations can launch balloons at multiple storm cells in the same window, and because each balloon streams its GPS position and radiosounding readings back to Selerys’s CIRRUS software in real time, the system builds a full vertical profile of the cloud from a single ascent, instead of the several passes an aircraft needs to piece together the same picture.

Each launcher in the Romania deployment was rated to cover up to 80,000 hectares, scaling the trial well past what a single aircraft or a network of ground-based generators could realistically reach in the same window.

What It Means for Water-Stressed Regions

Romania ran this trial because rainfall variability was already putting pressure on its agricultural regions, and that pressure isn’t going away on its own. Farmers and local officials involved in the trial described a practical difference: better water availability through dry stretches, and more confidence in a technology they watched work in real time instead of reading about months later in a report.

An independent, government-run validation at this scale is rare in weather modification. Most operators publish their own numbers and ask you to trust them. Romania’s Ministry of Agriculture published these.

Where This Fits Into Selerys’s Broader Results

Rain enhancement is one of four use cases Selerys runs on the same LAICO balloon platform, alongside hail mitigation, snow enhancement, and fog dispersal. The underlying hardware doesn’t change between them. What changes is the seeding agent and the altitude it’s released at: hygroscopic salt for rain and snow enhancement, silver iodide or hygroscopic salt for hail mitigation, released either inside the cloud or, for fog, at ground level where the fog itself sits.

That consistency matters for a region deciding whether to adopt the technology. A network built for rain enhancement in a dry season can be redirected toward hail mitigation the following spring, without new hardware and without retraining an operations team on a different system.

The post Case Study: A 300–500% Rainfall Increase in Romania’s National Balloon-Seeding Trial appeared first on Selerys.

Second paragraph to check spacing and typography.

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