Hurricane Hunters track Pacific winter storms
by Tech. Sgt. James B. Pritchett
403rd Wing Public Affairs
2/13/2007 - KEESLER AIR FORCE BASE, Miss. (AFNEWS) -- While most people flee when a pending storm is coming, Keesler AFB Airmen go right into the heart of storms to provide detailed information about storms to warn people of hazardous weather.
Airmen and WC-130J Hercules aircraft, also known as Hurricane Hunters, left here Feb. 12 for Anchorage, Alaska, for a month-long mission in support of the 2007 winter storm reconnaissance program.
In addition to two WC-130Js, Air Force Reserve Command's 403rd Wing officials put together a team composed of aircrew, operations, maintenance, aerial port and other specialties. Like tropical reconnaissance missions, winter storm routes can keep crews in the air more than 12 hours at a time.
The National Centers for Environmental Prediction, part of the National Oceanographic and Atmospheric Administration, directs the operations. When a tasking for a flight comes into the 53rd Weather Reconnaissance Squadron's deployed operations center at Elmendorf AFB, Alaska, a crew is alerted and aircraft maintainers prepare an aircraft for the sky.
Showtime and pre-flight are similar to the Hurricane Hunters' normal missions except, depending on weather, maintenance teams de-ice the aircraft just prior to take off.
Winter missions require crews to fly at higher altitudes than they normally fly in tropical weather systems, above 30,000 feet. The new WC-130 J-model is an improvement over the previous WC-130H in that it can fly much higher, allowing for collection of more data and thereby improving the forecast models even more than in the past.
"On average, the data we provide along with the NOAA aircraft lead to a 10 to 20 percent reduction in error in the targeted forecasts," said Lt. Col. Roy Deatherage, the mission commander for the 53rd WRS and an aerial reconnaissance weather officer since 1988. "As a result, numerical forecast guidance issued 48 hours prior to the events become as accurate as 36-hour lead time forecasts."
Use of weather reconnaissance aircraft have improved the forecast models more since 1999 than the previous 25 years of satellite data, according to the NCEP.
Unlike in tropical storms, on a winter mission the crew is not trying to pinpoint the center of the storm, in fact, there may not even be a "storm."
"Often, the crews are flying from one to four days in advance of a potential storm system in the Pacific that appears headed for either Alaska or the continental United States," Colonel Deatherage said.
On board the aircraft, the aerial reconnaissance weather officer and weather reconnaissance loadmaster take atmospheric observations at predetermined points along a flight track where the measurements are expected to have the greatest chance of improving the forecasts.
The weather reconnaissance loadmaster drops highly sensitive devices called dropsondes, which fall at about 2,500 feet per second, in areas of the atmosphere as requested by NCEP. As they fall toward the ocean, the dropsondes measure temperature, wind speed, humidity and pressure. Aircraft follow what are called synoptic patterns, huge ovals sometimes more than 3,000 miles round-trip.
Colonel Deatherage said during a typical tropical mission, dropsondes are released at certain points defined by the National Hurricane Center. This is usually four drops every time the aircraft passes through the eye with an additional four to eight per mission in the most significant wind bands. In contrast, Pacific winter missions average 16 to 22 sondes dropped. For impending Atlantic winter missions the average is lower, closer to five.
The information collected is checked onboard and then relayed by satellite to the NOAA Weather Service supercomputer, which incorporates it into the agency's numerical prediction models. This information helps "fill-in-the-blanks" or bolster the data in computer climate models that forecast storms and precipitation for the entire United States.
"The goal is to make a good forecast so cities can be prepared with snowplows, and other snow removal and mitigation equipment to diminish the impact of a winter storm on a city," Colonel Deatherage said. "If they are better prepared, like we've seen with several cities already this year, they can recover more quickly. That can be crucial for residents living in harm's way. These forecasts provide people in the path of the storms with warnings that can save lives."
While the Hurricane Hunters are patrolling the northern part of the Pacific Ocean, NOAA is using its Gulfstream G-IV aircraft to fly missions from Honolulu. Between the two units, they are able to cover the parts of the Pacific Ocean that directly affect the United States.
Each year, the 53rd WRS and NOAA rotate deployed locations to better improve the forecasting models. The G-IV flies higher and collects a slightly different data set than that of the WC-130J.
Since 1996, the two organizations have been flying these frosty missions in support of the NCEP.
People taking part in the first half of the deployment, about 57 of them, left for Anchorage Feb. 12 for two weeks. Another rotation departs about halfway through with all expected to return by March 13.
This project does not cover all of the 53rd WRS's winter taskings. Due to an unusually warm winter so far this year, the unit has only received minimal taskings for the East Coast of the United States to assist forecasters with pending Nor'easters.
The Hurricane Hunters normally fly several of these missions in support of the National Weather Service each season beginning Dec. 1 and ending April 30.
In seasons past, the tropical storm season, beginning June 1 and officially ending Nov. 30, has crossed over into the winter storm season. In 2005, the Hurricane Hunters flew winter storm missions and tropical missions at the same time. That year, the final storm of the hurricane season was recorded in early January.
(Courtesy of Air Force Reserve Command News Service)
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