Tired of faulty weather predictions? Apologetic meteorologists who predicted a nor’easter before a light dusting? One Wellesley man need not subscribe to such forecasts; he generates them from the roof of his Alden Road home.

Dr. John D. Halamka affixed a solar powered weather-monitoring device to the side of his house in Wellesley Hills a few weeks ago. The wireless device, which reads temperature, barometric pressure, rain accumulation and wind velocity, feeds reports to a website with a permanent URL established by Davis Instruments, the manufacturer of the device.

“It’s IT based,” he said. “It can instantly update…to websites, blogs, wherever you want it to go.”

But that’s not all. Halamka took it upon himself to register the device with Weather Underground, a network of personal and airport weather reports from around the world. Google generates much of its weather data from Weather Underground.

Because Halamka’s device serves as the lone weather reporter in the Wellesley Hills area – there are two similar devices in Wellesley: one near Fiske Elementary and one on Overbrook Road near Natick - by default, his reports are the ones read by anyone looking for local weather updates.

“Anyone who would search Google for ‘Wellesley Hills weather’ gets me,” he said.

Halamka takes his newfound responsibility seriously. He had to calibrate his device to “physical north,” which, as he explains, is about 15 degrees off from “magnetic north.”

His weather data has gone through a quality control process via the Citizen Weather Observation Program, which feeds individualized data reports to the National Oceanic and Atmospheric Administration (NOAA). The NOAA analyzes weather data for accuracy. Halamka’s data received a designation of “two thumbs up,” which is exemplary, he said.

“Basically what they said is if you compare what this thing is spitting out to Boston Logan [Airport], Hanscom Field [Air Force Base], the other major stations, turns out this thing is half a degree off in temperature,” he said.

His device has been placed in a national database to be referenced for climate modeling of the area, due to its high level of accuracy.

Halamka is not a meteorologist by trade. He is the chief information officer at Harvard Medical School, and while weather is not necessarily his forte, technology is. (To help nearby birds find drinkable water in winter, a bird bath in front of Halamka’s house is equipped with a device that keeps the water from freezing.) 

“In general, I find network censors to be cool,” he said. “Whether that’s something you wear in your shoes that’s measuring how fast you’re running … something that’s measuring the environment and these sorts of things. So actually, it all relates back to being a CIO.”

Amateur meteorologist, CIO, and add blogger to Halamka’s resume. Halamka has kept up a blog entitled “Life As A Healthcare CIO” for the last three years. Each day he posts something new for his some 10,000 daily readers. His weather censor device was the subject of his Jan. 6 post.

“I’m now a social networking meteorologist,” he said with a laugh. “Who would have thought?”

He’s found some personal uses for the at-home weather station as well. An avid outdoorsman, Halamka said he’d rely on his personal data service to gauge his daily kayak trips up the Charles River in spring. Yesterday morning, he accessed his weather interface to estimate the wind conditions at Dover’s Noanet Woodlands for a day of cross-country skiing.

Halamka does not intend to make money off of the information he provides but wants the information to be public. He has attached an icon with the weather reads on his blog. Personal and professional uses aside, it’s the thrill of being able to convert simple weather information into important data output that Halamka craves.

“All I did was buy this thing, plug it into the Internet, and within five minutes, I’m sharing hundreds of data points with the world,” he said. “That’s cool.”