Chronic Errors in Weather Forecasts Anger Public

Citizens are angry over erroneous weather forecasts made over the past four weeks by the Korea Meteorological Administration.

At 11 p.m. Friday afternoon, the weather watchdog said, “Rain will start in the southern provinces Saturday morning and will expand throughout the whole country in the afternoon.” The Chungcheong provinces were also expected to receive 5-30 millimeters of rain.

From early Saturday morning, however, the Chungcheong region had 50 millimeters of rain per hour. In the morning alone, Cheongju in North Chungcheong Province saw more than 150 millimeters of rain.

Seoul and Gyeonggi Province had unexpected rain from the morning, and at 8:35 a.m., a heavy rain alarm was issued.

Weather forecaster Park Gyeong-hui said, “As the North Pacific high expanded rapidly overnight, rain clouds that formed at the front of the typhoon arrived faster than expected and Seoul, southern Gyeonggi Province and the Chungcheong region saw a lot of rain.”

The weather authority had predicted for July 12, “The west coast of South Chungcheong Province and Jeju Island will have rain and Seoul and Gyeonggi Province will have hot temperatures.”

On the contrary, Seoul and Gyeonggi Province had rain at 3 a.m. that day. The rain stopped in the morning before showers came in the afternoon.

Angry citizens have posted complaints on the weather administration’s homepage in the wake of four consecutive weeks of erroneous forecasts.

“Since the weather report forecast rain in the afternoon or evening, I decided to move in the morning,” said one Web user. “But when I woke up, it was already raining early in the morning. It is absurd that the weather forecast even for the next five hours is wrong.”

Another Web user said, “When my daughter said she thought it would rain early tomorrow morning, I said the weather authority predicted rain in the afternoon. But it turned out that a sixth grader is better at predicting the weather than the weather authority.”

The unreliability of weather observation information and the limits of numerical weather prediction models are blamed for the series of erroneous forecasts.

A more sophisticated weather observation network makes forecasts more accurate, but the network of the West Sea and China is not as sophisticated as Korea’s. Moreover, numerical weather prediction models based on observed information are limited in their ability to accurately predict the weather.

“There are scientific limits in predicting when rain starts and how much rain with accuracy,” said weather official Kim Seung-bae. “However, in 2010 when we get the world’s second British numerical weather prediction model and third supercomputer that is 10 times as fast as its rival, we will have higher accuracy.”

firedy@donga.com