An official website of the United States government
Here's how you know
A .mil website belongs to an official U.S. Department of Defense organization in the United States.
A lock (lock ) or https:// means you’ve safely connected to the .mil website. Share sensitive information only on official, secure websites.

OBSERVERS PREDICT RAIN OR SHINE

18 Aug 2000 | Cpl. Kurt Fredrickson Marine Corps Air Station Iwakuni, Japan

An old man once created a device he said could tell the weather just by looking at it.  From his pocket, he pulled a golf ball-sized rock hanging from a piece of twine.  A "weather rock" he called it. 

It was a simple thing.  If the rock was bright on top it was nice out; gray if it was cloudy; wet when it was raining and if the rock turned white, you guessed it, it was snowing.   

Luckily, aboard the air station weather observers, forecasters and equipment predict weather with greater accuracy than a rock on a string.

Weather observers gather information so accurate forecasts can be provided to pilots and the air station community. 

"What we do, as far as weather is concerned, is keep everybody on the station safe," said Lance Cpl. Jarrod Atkinson, weather observer. 

Every hour, observers go outside and take readings from three separate thermometers.  They are used to get the wet bulb index temperature used to determine flag conditions aboard the station.  One measures air temperature, another measures an object in direct sunlight and the third measures humidity. 

While outside observers look to the sky to predict incoming weather and what pilots will have to fly through, observers are also trained to read the elevation of clouds by what they look like.  To get a better idea of the cloud elevation, weather balloons are released and tracked by eye.

"The gathering of information is done manually," Atkinson said.  "But the computers process everything."

Inside the weather office computers show observers the bigger picture.  The computers receive information gathered from other areas of the world to better understand what will happen here in the future.  Satellite images are also used to forecast the weather.

After the observers collect the information, the forecaster develops an outline of what is heading toward the air station. 

"Each morning we create a 72-hour forecast for the pilots and the public," said Staff Sgt. Grant Warkins, weather forecaster. 

After all the information is gathered, pilots depend on it the most, said
Lance Cpl. Zuriel Quinlan, weather observer.  The weather reports tell pilots if they can fly with their sight, or need the aid of instruments.

"For a pilot to even take off, he has to have a weather brief," Atkinson said.

To give pilots the best possible weather information, frequent forecasts must be made.

"Accurate forecasts are 72 hours, but general forecasts up to six days are a little off," Warkins said.

If observers take more than one reading per hour, the picture of what is to come gets clearer.  Although the technology observer's use helps them a lot, it's like the old mans weather rock, there's no surefire way to predict the weather.

"Our job is predicting the unpredictable," Quinlan said.  "There's millions of factors that go into it.  To get a forecast right all the time just wouldn't happen."