Hurricane Lenny Hits St. Croix
James A. Petrait
Hurricane Lenny was felt mainly during the afternoon of November 17, 1999 on St. Croix, VI. At a location near the Frederiksted part of the island at 17 deg. 43 min. N. Latitude and 64 deg. 53 min. West Longitude. Winds were estimated to be around 100 mph (according to radio reports) and were continuous for several hours and gusts continued for a day or 2 later. The wind direction was mainly from the north to east and did not reverse. The eye of the hurricane did not pass through here. The wind did not blow all of the vegetation from the trees and create a snowstorm-like look with flying debris as was the case with Hurricane Georges. However the gusts seemed to be selective depending on the terrain and did take the roof off a small shed in this area and blew some branches, signs, fences, and wires down. However other parts of the islands experienced greater difficulties and those near the shores were especially vulnerable.
According to the records. this was the first time that a Category 5 hurricane went from west to east so late in the hurricane season. Also the barometric pressure has been unusually low in this area for several weeks and continuous to be lower than normal on November 27 with a 1200 AST reading of 29.85 inches. Teachers and students should feel free to make use of the data to make graphs and as part of a study of an abiotic factor.
Below is the data which can be used as part of your lesson plan. I would suggest that you have the students make a graph from the data and then have them interpret the graph. Be aware that the times in the tables need to be converted to elapsed time in minutes to make a more accurate graph (to compensate for time measurements not being in the decimal system). I will post the graph from the first school to send me an accurate and complete line graph of all of the data points in the table. This should be in the form of a .jpg or .gif file of 300 kilobytes or less. Send an interpretation file with it in the email to which the file is attached.
BAROMETRIC PRESSURE CHANGES DURING HURRICANE LENNY ON ST.CROIX
TIME IS AST BAROMETRIC PRESSURE (BP) IS IN INCHES DATE IS 11/17/99
LOCATION: ST. JOSEPH HIGH SCHOOL, FREDERIKSTED, VI 00840
17 DEG. 43 MIN. NORTH LATITUDE, 64 DEG. 53 MIN. WEST LONGITUDE
OBSERVER: JAMES A. PETRAIT
TIME BP TIME BP TIME BP TIME BP
0000 29.59 1200 29.32 1530 28.97 1900 29.29
0100 29.56 1230 29.26 1600 28.97 1930 29.32
0400 29.53 1300 29.21 1630 29.06 2000 29.35
0600 29.47 1330 29.12 1700 29.09 2400 29.38
0800 29.50 1400 29.03 1730 29.18
1000 29.47 1430 29.00 1800 29.21
1100 29.41 1500 29.00 1830 29.26
ADDITIONAL REFERENCE POINTS:
ON 11/16/99 AT 1200 THE BP WAS 29.65
ON 11/18/99 AT 0700 THE BP WAS 29.50
ON11/18/99 AT 1900 THE BP WAS 29.62
NORMALLY THE BP STAYS AROUND 30.00
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©2000, James A. Petrait firstname.lastname@example.org