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Preliminary Report
Hurricane Flossie
7-14 August 1995

Edward N. Rappaport
National Hurricane Center
4 December 1995

Tropical Depression One-E
Hurricane Adolph
Hurricane Barbara
Hurricane Cosme
Tropical Storm Dalila
Tropical Storm Erick
Hurricane Flossie
Tropical Storm Gil
Hurricane Henriette
Hurricane Ismael
Hurricane Juliette

[1995 East Pacific Hurricane Season]

Some tropical cyclones in the eastern North Pacific appear to develop in close association with tropical waves. Others, like Hurricane Flossie, are apparently generated in a different, "monsoon-like" mode of formation in which tropical waves may not be the primary large-scale forcing.

a. Synoptic History

Hurricane Flossie formed within a large, deep cyclonic circulation and low pressure area that dominated the weather in the tropical eastern North Pacific Ocean near the end of the first week of August. The southern and southeastern part of this area was defined by a long stretch of west-southwesterly winds and by cloudiness in the eastern part of the ITCZ, which had pivoted northward through the Gulf of Tehuantepec (toward Tropical Storm Gabrielle in the western Gulf of Mexico).

The large circulation was well-developed by August 7 when thunderstorm activity began to increase and become focussed a few hundred miles southwest of Acapulco (perhaps in association with a tropical wave analyzed in the vicinity). Surface pressures were already low across the region as implied by a ship report of 1004.0 mb made near Acapulco at 0000 UTC on the 7th. Based primarily on surface analyses, this system is estimated to have become Tropical Depression Seven-E at 1200 UTC on the 7th (Table 1 and Fig. 1 [42K GIF]).

The intensity implied by satellite images continued to lag the estimates derived from surface reports. Satellite analysts at the NHC and NESDIS Synoptic Analysis Branch (SAB) had Dvorak T-numbers of 2.0 (30 knots) at 0000 UTC on the 9th (Figs. 2 [24K GIF] and 3 [25K GIF]). However, two ships then had pressures in the 996-999 mb range and observations from ships imply that winds were likely of tropical storm force. It is now estimated that the depression became Tropical Storm Flossie at 1800 UTC on the 8th.

Flossie moved toward the northwest at 5 to 10 knots for most of its seven-day existence, to the south-southeast of a deep-layer-mean anticyclone. On this course, the center remained offshore, but the southwestern coast of Mexico and later the southern Baja California peninsula were buffeted by gusty winds and locally heavy rain.

A northeasterly vertical wind shear diminished and very cold cloud tops then developed. Flossie reached hurricane strength on the 10th and its peak intensity, 70 knots, was maintained for about 24 hours beginning at 1200 UTC that day. An embedded warm spot appeared in satellite pictures and the center of circulation made its closest approach to land during that period, when it passed about 65 n mi to the southwest of the peninsula.

Weakening ensued over cooler waters. Flossie dropped below hurricane strength on the 12th and turned westward. It was a depression on the 13th and dissipated on the 14th.

b. Meteorological Statistics

Figures 2 and 3 show the curves of estimated minimum central pressure and maximum one-minute wind speed versus time, respectively, and the data upon which they were based. The Air Force Global Weather Central (AFGWC), the NHC Tropical Analysis and Forecast Branch (TAFB; TSAF in figures), and the NESDIS Synoptic Analysis Branch (SAB) supplied the Dvorak classifications. The figures show the early lag between Dvorak technique intensity estimates derived from satellite pictures and estimates made from surface analyses.

An observation of tropical storm force winds was received from Cabo San Lucas, Baja California which had 35 knot winds (over 10-minutes) and a gust to 48 knots at 0300 UTC on the 11th. Nearby San Jose del Cabo had a gust to 55 knots according to amateur radio reports. Selected significant ship observations are as follows:

Ship IDDate/Time
Lat. (°N)Lon. (°W) Wind Speed
LAMF208/234019.0105.8 56-65 

Some data from the ship LAMF2 are likely unrepresentative.

c. Casualty and Damage Statistics

The El Nuevo Herald newspaper reported five lives lost in Puerto Vallarta and Mazatlan. Amateur radio reports stated that two people drowned in Cabo San Lucas. No quantitative estimates of damage have been received.

d. Forecast and Warning Critique

Flossie was of tropical storm or hurricane intensity for only about four days so there were few forecasts to evaluate. On average, the NHC track and intensity errors for that period were comparable to previous averages.

Table 2 lists tropical storm warnings and watches issued by the Government of Mexico.

Table 1. Preliminary best track, Hurricane Flossie, 7-14 August 1995.
Position Pressure
Wind Speed
Lat. (°N)Lon. (°W)
7/120015.2104.2100130 Tropical Depression
180015.3104.7100130" "
8/000015.5105.2100030" "
060015.8105.799930" "
120016.2106.099830" "
180016.6106.399735 Tropical Storm
9/000017.1106.599440" "
060017.6106.899150" "
120018.0107.498855" "
180018.5107.998560" "
10/000019.1108.498360" "
120020.0109.397970" "
180020.5109.797870" "
11/000021.3110.397970" "
060022.1111.098070" "
120022.9112.098265" "
180023.5113.298365" "
12/000024.0114.398465" "
060024.2114.998760 Tropical Storm
120024.5115.799060" "
180024.7116.599455" "
13/000024.7117.299740" "
060024.7118.0100030 Tropical Depression
120024.7118.4100230" "
180024.7118.8100425" "
14/000024.7119.2100625 Dissipating
10/180020.5109.797870 Minimum Pressure

Table 2
Hurricane Flossie watch and warning summary
09/1500Tropical Storm Warning issued Punta Tejupan to Cabo Corrientes
09/2100 Tropical Storm Watch issued Baja California south of La Paz
Tropical Storm Warning discontinued Punta Tejupan to Cabo Corrientes
10/1500Tropical Storm Warning issued Baja California south of La Paz
11/1000Tropical Storm Warning extended Baja California to San Juanico on west coast and Loreto on east coast
12/0000 Tropical Storm Warning discontinued All areas

Brian Maher
Jack Beven

Last updated January 2, 1999