For about how many hours was hurricane Floyd (1999) of strength category 4?

Dear flinfl-ga,

Hurricane Floyd (1999) reached category 4 on two occasions. The first
from 9/12/99 1800 to 09/14/99 1200
(36 hours), and  09/15/99 0600 to 09/15/99 1200 (6 hours)

You can download the full data from
http://weather.unisys.com/hurricane/atlantic/1999/index.html
and click on the Hurricane Floyd data to download the file
http://weather.unisys.com/hurricane/atlantic/1999/FLOYD/track.dat
 
This is the relevant extract:

              LAT      LON   TIME     WIND  PR
HURRICANE-3  23.20  -67.40 09/12/18Z  115   940
HURRICANE-4  23.40  -68.70 09/13/00Z  125   931
HURRICANE-4  23.60  -70.00 09/13/06Z  135   922
HURRICANE-4  23.90  -71.40 09/13/12Z  135   921
HURRICANE-4  24.10  -72.90 09/13/18Z  125   923
HURRICANE-4  24.50  -74.00 09/14/00Z  115   924
HURRICANE-4  24.90  -75.30 09/14/06Z  105   927
HURRICANE-3  25.40  -76.30 09/14/12Z  105   930

HURRICANE-3  27.10  -77.70 09/15/00Z  115   933
HURRICANE-4  28.20  -78.50 09/15/06Z  110   935 
HURRICANE-3  29.30  -78.90 09/15/12Z  100   943

This site also provides detailed additional information.
http://www.nhc.noaa.gov/1999floyd.html

I hope this answers your question. If it does not, or the answer is
unclear, then please ask for clarification of this research before
rating the answer. I shall respond to the clarification request as
soon as I receive it.
Thank you
answerfinder

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