By Jackie Miller
In the fall of 2023, Tulare Irrigation District’s General Manager Aaron Fukuda sat in a packed session at the ACWA conference, listening to Rob Doornbos of Weather Tools talk about their water year precipitation forecast. Fukuda wasn’t expecting much, maybe some vague guidance with probabilities. But then Doornbos began walking through the model’s past performance — and it caught Fukuda’s attention.
“He Left Us Hanging!”
Doornbos shared a case study of the previous year (water year 2022-23) when most forecasters had called for another year of drought. But Weather Tools’ model saw something different. Their annual precipitation forecast—released the first week of November, months ahead of any state updates —projected “20 to 40% above normal precipitation.” That bold prediction proved to be right on target. And so was every forecast since 2016.
Fukuda sat up straighter.
“I remember thinking, ‘Wait… who is this guy?’” he said, laughing. “He wasn’t flashy. He wasn’t selling hard. He just quietly walked through the numbers, the verification, and the decisions that the California Rice Commission made because of it.”
As the presentation continued, anticipation grew. Everyone in the room wanted to know: What was the Weather Tools forecast for the coming water year, 2023–24? And then Doornbos walked off the stage.
“He left us hanging!” Fukuda said. “I was on the edge of my seat. What’s the punchline?!”
The punchline, as it turns out, was the product — the California Annual Precipitation (CAP) forecast, which was proprietary and only available to subscribers. When the session ended, Fukuda made a beeline to the Weather Tools booth.
“That day, I didn’t just learn about the forecast,” he said. “I met Rob. And honestly, it was Rob who sold me. I could tell right away, he’s grounded, humble, and really immersed in the science of weather forecasting.”
They started talking that afternoon and didn’t stop.
Over the next few weeks, Fukuda asked more questions to understand how Weather Tools builds its forecasts, how early the information becomes available (November), and how well it had performed in past years (The answer? All of them). Beyond the initial forecast, Weather Tools provides monthly progress reports and insights to its customers.
But what stood out most to Fukuda was the relationship. Behind the forecast was a partner, someone who cared as much about getting it right as he did. “Rob’s not just out there trying to grow a business, he’s in it to help people make better decisions. I can pick up the phone and talk to him. It feels like a partnership more than a vendor relationship.”
What if He’d Known
Looking back, Fukuda said if he’d had access to CAP during water year 2022–23, he would’ve made different operational decisions.
“That was the year we were all expecting another dry year. But if I’d seen Doornbos’s forecast showing significantly above normal precipitation I would’ve approached things differently. We were caught flat-footed in some ways. While we did have a fantastic 2023 recharge and irrigation season, the early notice might have been useful in preparing our District and growers better.”
That missed opportunity made his 2023-24 subscription decision an easy one.
Taking the Leap in 2023-24
Last year, with the forecast in hand months before the B-120 or other state updates, Fukuda was able to make water management decisions early and with confidence.
“I had to tell the board, ‘We’re taking a risk here,’” he said. “But I had Doornbos’s performance record to back it up. If we waited, we’d have missed the window.”
That early planning paid off.
“We were already talking about doing this based on Weather Tools’ forecast,” Fukuda recalled. “Then the B-120 came out, and we looked like we were just really smart. But we already had the plan in motion months ago.”
And Inflow in 2024–25
Not long after subscribing, Fukuda told Doornbos, “The precipitation forecast is great… but if we could know reservoir inflow, that would be a game-changer.” So, Doornbos got to work.
He began exploring whether the seasonal precipitation forecast could be extended to estimate total water year inflow for specific reservoirs. A regression analysis revealed a strong relationship between the two. Doornbos ran it across the full historical record for 18 key reservoirs, testing it year by year. The results were remarkably accurate. From that breakthrough, the California Reservoir Annual Forecast Tool (CRAFT) was born.
What started as a conversation became a new capability.
For Tulare Irrigation District, it meant one more step toward proactive planning. With CRAFT’s November inflow forecast, Fukuda and his team had something rare: lead time and confidence. Instead of waiting for late-season updates or reacting to uncertain conditions, they could move early, with purpose.
“We’re not just reading forecasts,” Fukuda said. “We’re using them to make real decisions.”
More Than a Forecast
When asked what the biggest return on investment has been, Fukuda didn’t hesitate: trust.
“There are a lot of people who can throw numbers at you,” he said. “But to have a relationship where I can pick up the phone, talk through what I’m seeing, and know the person on the other end actually cares? That’s worth a lot.”
He continued, “If someone’s on the fence about using CRAFT, I’d just say this: You don’t know what you’re missing until you try it. If you want to be ahead — not just informed — you need this forecast.”
Then he smiled. “And hey, if folks don’t want to subscribe… that’s okay too,” he added with a laugh. “It just gives us the edge.”
Jackie Miller is the Manager of Data & Product Services at Weather Tools, where she
combines a curiosity about weather data with a passion for storytelling. She leads the development of monthly forecast reports, using numbers and narrative to bring clarity to customers navigating complex water year decisions. You can reach her at Jackie@weathertools.org
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