PART II: METEOROLOGICAL DISCUSSION 



3. Hurricane Danny was identified as a poorly defined tropical depres- 

 sion on 12 August 1985 while located just south of the western tip of Cuba.* 

 The minimum central pressure at the time was a relatively high 1010 mb.** 

 During the next 24 hr, the central pressure increased slightly to 1011 mb., 

 and the system showed little change in organization or strength. By the morn- 

 ing of 14 August, the depression had passed through the Yucatan Straits into 

 the Gulf of Mexico. The central pressure began dropping, and the winds rap- 

 idly increased to tropical storm speed of 35 knots. During the following 



24 hr, the storm intensified very rapidly, reaching hurricane intensity early 

 on the morning of 15 August 1985. Danny was then located about 225 miles 

 south of New Orleans, La., moving toward Port Arthur, Tex. During the day, 

 the hurricane assumed a more northerly course and made landfall late during 

 the evening of 15 August 1985, just east of Grand Chenier, La. 



4. Danny was classified as a minimal hurricane, a Category 1 on the 

 Saf fir-Simpson scale, which ranges from a minimum of 1 to a maximum of 5. The 

 hurricane attained its greatest intensity at the time of landfall with maximum 

 sustained winds of about 90 mph and a minimum central pressure of 987 mb. 

 Danny weakened rapidly after moving inland across Louisiana and within 20 hr 

 had weakened to a tropical depression. An unusual feature of Danny's movement 

 through the Gulf of Mexico was the remarkably constant speed of translation 

 during the 2 days prior to landfall. From 1200 Greenwich mean time (Gmt) 



13 August to 1200 Gmt 15 August, 12-hr averages of Danny's forward speed 

 ranged from 13.2 mph to 14.2 mph. The distances traversed during four 12-hr 

 intervals beginning at 1200 Gmt 13 August were 170, 159, 158, and 160 statute 

 miles. Average speeds for these distances were 14.2, 13.2, 13.2, and 

 13.3 mph, respectively. Figure 1 shows the approximate track of Danny. 

 Table 1 contains the preliminary best-track information. 



* The meteorological discussion and information contained in Table 1 are 

 taken from the preliminary report on Hurricane Danny provided by the 

 National Hurricane Center. 

 ** A table of factors for converting non-SI units of measurement to metric 

 (SI) is presented on page 3. 



