Weather service is zeroing in on storms
Changes will help weather bureaus reduce false alarm numbers
Staff writer
For most Kansans, the issuance of a severe weather warning is about as fear-inspiring as the label attached to a mattress warning against its removal.
However, Kansas National Weather Service officials hope that's about to change.
National Weather Service offices in Wichita and Dodge City are testing a new system this season which will zone in on severe weather warning areas.
And statewide, the NWS is conducting a field test which changes its criteria for issuing severe thunderstorm warnings.
New technology
New technology, which allows forecasters to better predict a storm's path, will be used this season at 16 NWS offices nationwide.
In Kansas, the Dodge City and Wichita NWS offices are two of the test sites. The Wichita weather service office covers Marion County.
"In the past our warnings have all been county-based," explained Dick Elder, lead meteorologist at the Wichita NWS office. "With this new technology we can issue warnings for the portions of a county which are directly affected."
Elder recalled an instance 15 years ago when a tornado hit Hesston in neighboring Harvey County.
"As I recall all of Marion County also got a tornado warning, but the only place (in the county) at risk was the southern portion," Elder said.
"Now we have the technology to issue warnings using a polygon or a projected track," he explained. "Our forecasters can use the system to predict a storm's movement.
"Now with the digital age we can do polygons based on lat (latitude) lines which can be plotted and actually seen."
The change means that warnings will be issued for specific areas rather than entire counties. Thus, areas may be defined as bordering different cities or significant geographical areas.
"That means the southern part of Marion County might be in a tornado warning, while the northern part of Marion County could be in a severe thunderstorm warning," Elder explained.
"Taxpayers expect us to be accurate as we possibly can," Elder noted. "This will drastically reduce our false alarm area."
Criteria change
In an unusual move for the National Weather Service, the state of Kansas was given the go-ahead this severe storm season to conduct a field test changing the criteria for a severe thunderstorm warning.
The change means Kansans will see fewer storm warnings. However, they will need to pay more attention to the ones that are issued because the storms will have the potential to be more severe.
Weather bureaus covering Kansas will not issue a severe thunderstorm warning until they receive reports of hail at least one-inch in diameter, about the size of a quarter. In the past, the criteria for issuing a warning was 3/4- inch hail or penny size.
"We saw our first thunderstorms in south central Kansas around the end of February," Elder explained. "If the old criteria had been in effect we would have already issued four severe thunderstorm warnings this year (as of Monday). Instead, none have been issued."
Elder noted those late February storms did not cause damage so a warning was not necessary.
The change is an experiment intended to make people take warnings more seriously, Elder said. He noted penny-size hail in this part of the country is "nothing out of the ordinary" and "doesn't cause damage."
Studying past severe warnings, Elder said his office discovered at least one-third of the warnings issued each year qualified on the basis of 3/4-inch hail only.
"With the help of local media we hope people will take more credence in the warnings we do issue," Elder said.
Local weather bureaus will still issue significant weather advisories if a storm is packing 40 to 55 mph winds, he said.
Elder noted the National Weather Service is extremely cautious in changing any of its criteria.
"This has been a big deal to be allowed to test this," he said. "The 3/4-inch criteria has been around for a long time."
In fact, he noted the criteria dates back to the DC-3 when it was determined 3/4-inch
hail could dent the wings of the plane.
"The question is: Is that still a valid number today?" he asked.
Elder noted the change is just a field test which means there are no guarantees.
"I certainly encourage people to provide feedback about what they think about the change," Elder said. "If they like it, let us know."
March 14-18 is severe weather awareness week in Kansas, just before Kansas' peak tornado months of April, May, and June.
Last year, Kansas was struck by a record 122 tornadoes, according to information provided by adjutant general's department. That number is 69 above normal and exceeds the previous record of 116 set in 1991.
Fifteen tornadoes occurred July 7 in Russell County while 10 occurred May 12 in Harper County. In Sumner County, 11 tornadoes were reported, one causing $20.3 million in damage and two-thirds of the entire state's total dollar damage.
Interestingly enough there were no deaths and only six injuries.
