WORLD METEOROLOGICAL ORGANIZATION
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RA IV HURRICANE COMMITTEE
THIRTY-FIRST SESSION
NASSAU, BAHAMAS
20 TO 24 APRIL 2009 / RA IV/HC-XXXI/Doc. 4.2(4)
(26.II.2009)
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ITEM 4.2
Original: SPANISH

EXAMINATION OF THE PREVIOUS HURRICANE SEASON

Reports on hurricanes, tropical storms, tropical disturbances and
flooding associated with those events occurring in 2008

(Submitted by Mexico)

Description of the cyclone season in Mexico

The general behaviour of the tropical cyclones during 2008 resulted in a VERY ACTIVE season for Mexico. It is regarded as very active not so much In terms of intensity as on account of the total number of direct impacts on the Mexican coasts.

A total of eight tropical systems affected the Mexican coasts directly, five of which originated in the north-eastern Pacific and three in the Atlantic. The average number of tropical cyclones to directly affect Mexico (originating from both oceans) for the period from 1970 to 2008 was 4.3 cyclones per year.

Summary table of tropical cyclone activity in 2008 for Mexico

General description of the season / Tropical depressions / Tropical storms / Moderate hurricanes (I-II) / Intense hurricanes
(III-IV) / Total TCs over Mexico
VERY ACTIVE / 2 / 5 / 1 / 0 / 8

Cyclones affecting Mexico originating in the Pacific

During the 2008 season, five cyclones directly affected the Pacific coasts. In chronological order, they were tropical depression No 5-E, which made landfall on the night of 6 July, near Port Lázaro Cárdenas, Michoacán, with maximum sustained winds of 55km/h and gusts of 75km/h. On its short trajectory, it brought heavy rainfall over the central Pacific coastal states of Mexico, the Cerro de Ortega station, Colima, reporting a maximum accumulated rainfall in 24 hours of 330mm. It caused isolated landslips and flooding, but there no official reports of fatalities.

The second cyclone directly affecting Mexico was tropical storm Julio, which made landfall during the night of 24August in the vicinity of the village of La Aguja, Baja California Sur (BCS); at 16:00 GMT on 24 August the Cabo San Lucas automatic station reported sustained winds of 70 km/h with gusts of 95 km/h. The maximum rainfall accumulated in 24 hours was 166 mm in Loreto, BCS on 24 August and 130 mm at Mulegé, BCS on 25 August. One fatality was reported (preliminary data). No major material damage was recorded.

Another cyclone directly affecting the country was tropical depression “Lowell”, which made landfall twice, first 50 km north-north-west of Cabo San Lucas, BCS, with maximum sustained winds of 45 km/h and gusts of 65 km/h, at approximately 04:00 hours local time on 11September and around 20:00 hours; it made a second landfall at the village of San Ignacio, north of Sinaloa, with maximum sustained winds of 45 km/h and gusts of 65 km/h. Maximum rainfall in 24 hours of 160 mm was reported at Nachuquis, Sonora. Flooding and material damage were reported in the states of Sinaloa and Sonora. There were no official reports of fatalities associated with “Lowell” in Mexico.

The fourth cyclone that affected Mexico was hurricane “Norbert”, which made landfall twice on 11 October, first in the vicinity of the village of Puerto Cortés, BCS, with maximum sustained winds of 165 km/h and gusts of 205 km/h, as a category II hurricane, at approximately 11:30 hours local time, and then made a second landfall 25 km south-east of Yavaros, Sonora, with maximum sustained winds of 140 km/h and gusts of 165 km/h, as a category I hurricane, shortly after 22:00 local time. At 02:00 GMT on 12 October the station at Los Mochis airport (MMLM) reported maximum wind speeds of 90km/h with gusts of 110km/h. The highest rainfall in 24 hours was at Ciudad Constitución, BCS with 121.3mm. The official figure reported by the Civilian Defence Central Office was five fatalities of people swept away by the river in the village of Alamos, Sonora. Significant material damage was reported with flooding in the states of Baja California Sur, Sonora and Sinaloa.

The fifth cyclone originating in the Pacific to hit Mexico in 2008 was the tropical storm “Odile”, 50 km south-south-west of Zihuatanejo, Guerrero, the same day as “Norbert” on 11October with maximum sustained winds of 100km/h. The most intense rainfall reported was 175mm at Copala, Guerrero. There were no reports of damage or deaths associated with “Odile” in Mexico.

Cyclones affecting Mexico originating in the Atlantic

Three Atlantic cyclones affected Mexico during the 2008 season.

The first was tropical storm “Arthur” which followed a route over southern Quintana Roo, Campeche and eastern Tabasco, as it evolved from a storm into a tropical depression from 31May to 1June. The remnants of “Arthur” caused heavy rainfall in south-eastern Mexico, with a maximum accumulation in 24 hours of 212mm at Pijijiapan, Chiapas. No significant damage or deaths associated with “Arthur” were reported in Mexico.

The second cyclone to affect the east coast of Mexico was tropical storm “Dolly”, which made landfall in the southern part of Laguna de Nichupté, south of Cancún, Quintana Roo, at approximately 01:30 hours local time on 21 July, with maximum sustained winds of 85 km/h and gusts of 100 km/h. After crossing the Gulf of Mexico, it moved back into Mexican territory, crossing the border with the United States near the village of Nuevo Laredo, Tamaulipas, with maximum sustained winds of 65 km/h and gusts of 85 km/h, on 24 July at 11:45 hours local time. “Dolly” brought heavy rainfall to the states of Quintana Roo and Yucatán when it first passed over Mexico, and later intense rainfall in Tamaulipas, Nuevo León and Coahuila on its second pass. The maximum rainfall in 24 hours was 162.2 mm at Matamoros, Tamaulipas. No fatalities associated with “Dolly” were reported on Mexican territory.

The third cyclone directing affecting the Atlantic coast was the very minor tropical storm “Marco”, with the impact centred 30km east of Misantla, Veracruz, with maximum sustained winds of 65km/h. Maximum rainfall was reported in El Pujal, San Luis Potosí with 201mm accumulating in 24 hours. No damage or deaths associated with “Marco” were reported.

Functioning of the Warning System and Mexico’s National Meteorological Service

The National Meteorological Service ensured constant surveillance of tropical cyclones throughout the 2008 season. A total of 384 tropical storm advisories were issued for the Pacific and 285 advisories were issued for the Atlantic Ocean.

Summary of tropical storms for the 2008 season in Mexico

Tropical cyclone / Path in km / Duration (hours) / Advisories issued / Arrival on Mexican territory / Maximum rainfall accumulated in 24 hours (mm) / Human casualties and material damage (*)
Place / Maximum wind speed / Fatalities
North-western Pacific Ocean
Tropical depression 5-E / 785 km / 36 hours / 13 / 10 km W of Lázaro Cárdenas, Michoacán / 55 km/h / 330 mm at Cerro de Ortega, Colima / 0
Tropical storm “Julio” / 1450 km / 72 hours / 25 / La Aguja, Baja California Sur / 75 km/h / 166 mm at Loreto, Baja California Sur / 1
Tropical depression “Lowell” / 1985 km / 120 hours / 37 / Cabo San Lucas, BCS San [San Ignacio, Sinaloa] / 45 km/h / 160 mm at Nachuquis, Sonora / 0
Hurricane “Norbert” / 3400 km / 204 hours / 56 / Puerto Cortés, BCS and [Yavaros, Sonora] / 165 km/h and [140 km/h] / 121.3 mm at Cd. Constitución, BCS. / 5
[official figure]
Tropical storm “Odile” / 2035 km / 96 hours / 35 / 50 km SSW of Lázaro Cárdenas, Mich. / 100 km/h / 175 mm at Copala, Guerrero / 0
Atlantic Ocean
Tropical storm “Arthur” / 650 km / 33 hours / 12 / SW of Chetumal, Quintana Roo / 65 km/h / 212 mm at Pijijiapan, Chiapas / 0
Tropical storm “Dolly” / 2100 km / 96 hours / 38 / Laguna de Nichupté, Q.R. and [Nuevo Laredo, Tam.] / 85 km/h and [65 km/h] / 162.2 mm at Matamoros, Tamaulipas / 0
Tropical storm “Marco” / 420 km / 36 hours / 13 / 30 km east of Misantla, Veracruz / 65 km/h / 201 mm at El Pujal, San Luis Potosí / 0
* Preliminary figures for human casualties and material damage. The official figures will be compiled at the national meeting of the Working Group for preparing Mexico’s report to the RA IV Hurricane Committee. Mexico City, 13 March 2009.

Hydrometeorological phenomena in Mexico in 2008

In summary, in 2008 Mexico was affected by the passage of eight tropical cyclones, 52 cold fronts, 37 tropical waves and five winter storms (cold, low pressure systems). The NMS recorded a total of 632 intense storms (exceeding 70mm/24 h), with the highest accumulated rainfall at Las Perlas, Veracruz, from 6 to 7 September with 374mm, caused by tropical wave No27.

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