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(Kenneth Chang ABC News-1998)
Why Did Mitch Keep Raining?
When Mitch formed in the Caribbean in 1998,
it was one of the strongest hurricanes on record, with sustained
winds reaching 180 mph, gusts topping 200 mph. Before hitting
Florida with tornadoes, heavy rains and high wind, Mitch spent
days lashing Central America, killing thousands.By the time
Hurricane Mitch hit Honduras, its winds had subsided to 105
mph. It faded to a tropical storm, then a tropical depression.
Yet it refused to die, and unleashed rain and destruction onto
Central America. In a couple of days, several feet of rain fell–probably
more than New York City or Seattle gets in a full year. The
waters triggered huge mudslides and floods that buried and drowned
more than 10,000 people. "It’s not unusual for a hurricane
or tropical storm to meander around," says Trisha Wallace,
a meteorologist at the National Hurricane Center in Miami. A
number of factors–water temperatures, wind, air pressure–determine
where a hurricane goes, how long it takes to get there and how
strong it blows.
Forecasters
Got It Wrong
Hurricane Mitch formed in the
southwestern Caribbean Sea on Oct. 22, 1998, and grew into one
of the most intense hurricanes ever. At its center, air pressure–a
measure of the strength of the storm–dropped to 905 millibars,
tied with deadly Camille of 1969 for the fourth lowest air pressure
ever seen in an Atlantic hurricane. Gilbert of 1988 holds the
record at 888 millibars. On a typical day, surface air pressure
is usually 1013 milibars, or 14.7 pounds per square inch. The
lower it drops, the stronger winds and the stronger the storm.
For several days, the storm moved northwest as expected. Forecasters
predicted Mitch would then turn north into the Gulf of Mexico.
It didn’t, blocked by a high-pressure system over the eastern
United States. Instead, it bumped along westward, slowly, into
Central America and kept going. "The fact Mitch didn’t
completely die over land is a bit unusual," says Jack Bleven,
another National Hurricane Center meteorologist. It’s not
unheard of, though. Hurricane Danny ,in 1997 for instance, made
landfall near the Mississippi River delta, weakened to a tropical
depression. But Danny kept going, north through Mississippi,
then curving east through Georgia, South Carolina and North
Carolina, re-emerging over the Atlantic, where it strengthened
back into a tropical storm.
Tight Winds
Kept it Going
Mitch similarly maintained its tropical
depression strength as it stalled over Honduras. Its tight circulation
pattern may have made the winds two or three miles above the
surface less susceptible to the weakening effects of landfall.
"That can help sustain a storm until … it gets to
conditions favorable for strengthening," Bleven says. Never
too far from the ocean, Mitch continued sucking moisture from
the Atlantic and dumping it as rain. The mountainous terrain
may have contributed to the downpours by guiding the damp air
upward into the storm. And when Mitch neared the Pacific Ocean,
the moisture there helped fuel its winds. Mitch then made a
U-turn and crossed back over Central America and into the Gulf
of Mexico. From there, Bleven says, it started acting like a
run-of-the-mill late-season tropical storm, zipping across the
Gulf, across the Florida peninsula and out into the Atlantic
for its last hurrah.
Links below take you to news stories and other information
on Mitch's rampage.
Reprinted
from USATODAY.COM
Mitch relief
Stories by USA TODAY and The Associated Press
Caribbean
USA
Damage information
Graphics, satellite images and observations
Graphics
Satellite images
Observations
Flight reports
- A forecaster at the Mount Holly Forecast Office - James
Eberwine - flew aboard a NOAA (WP-3D) flight into Mitch
while it was a strong Category 4 hurricane in the Caribbean.
Click
here for his report.
Other Hurricane Information-
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