Tag Archives: Tehuantepec

Hurricane Agatha Makes Landfall Near Puerto Angel, Mexico

Hurricane Agatha made landfall near Puerto Angel, Mexico on Monday afternoon. At 5:00 p.m. EDT on Monday the center of Hurricane Agatha was located at latitude 15.7°N and longitude 96.6°W which put it about 5 miles (10 km) west of Puerto Angel, Mexico. Agatha was moving toward the northeast at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 105 m.p.h. (165 km/h) and and there were wind gusts to 125 m.p.h. (200 km/h). The minimum surface pressure was 974 mb.

A Hurricane Warning was in effect for the portion of the coast from Salina Cruz to Lagunas de Chacahua, Mexico. A Hurricane Watch was in effect for the portion of the coast from Salina Cruz to Barra de Tonala. Tropical Storm Warnings were in effect for the portions of the coast from Lagunas de Chacahua to Punta Maldonado and from Salina Cruz to Boca de Pijijiapan, Mexico.

Hurricane Agatha maintained its intensity until it made landfall on the southern coast of Mexico just to the west of Puerto Angel on Sunday afternoon. A reconnaissance aircraft reported a circular eye with a diameter of 35 miles (55 km) at the center of Hurricane Agatha. The eye was also visible on satellite images. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. The ring of thunderstorms was weaker south of the eye. Bands of showers and thunderstorms were revolving around the core of Agatha. Storms near the core generated strong upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Agatha increased slightly in size on Sunday. Winds to hurricane force extended out 25 miles (40 km) from the center of Agatha’s circulation. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Hurricane Agatha was 17.8. The Hurricane Size Index (HSI) was 8.8 and the Hurricane Wind Intensity Size Index (HWISI) was 26.6.

An upper level trough over northern Mexico will steer Hurricane Agatha toward the northeast during the next 24 hours. On its anticipated track, Hurricane Agatha will move inland over Oaxaca. The center of Agatha could pass northwest of Tehuantepec and Salina Cruz on Monday night. Hurricane Agatha will bring strong winds and locally heavy rain to Oaxaca. Heavy rain is likely to cause flash floods in some locations. Agatha could produce a storm surge of ten feet (three meters) along portions of the coast of Oaxaca. Hurricane Agatha could cause localized serious damage.

The lower part of Hurricane Agatha’s circulation will weaken quickly when it moves over mountains in southern Mexico. The upper level trough over northern Mexico will steer the middle and upper parts of Agatha’s circulation toward the northeast during the next 24 hours. The middle and upper parts of Hurricane Agatha could emerge over the Bay of Campeche or northwest Caribbean Sea in a couple of days. Those parts of Agatha’s circulation could contribute to the development of a tropical or subtropical cyclone over the Gulf of Mexico, northwest Caribbean Sea or western Atlantic Ocean later this week.

Small Tropical Storm Vicente Forms Southwest of Guatemala

Small Tropical Storm Vicente formed southwest of Guatemala on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Vicente was located at latitude 13.3°N and longitude 92.2°W which put it about 110 miles (180 km) south of Tapachula, Mexico.  Vicente was moving toward the northwest at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1005 mb.

Tropical Storm Vicente formed out of a tropical wave that almost produced a tropical depression over the western Caribbean Sea earlier this week .  An area of low pressure developed within the tropical wave, but the low moved over Honduras before it could organize enough to be designated as a tropical depression.  The low continued to organize once it moved over the Eastern North Pacific Ocean southwest of Guatemala.  A distinct low level center of circulation was evident on visible satellite imagery on Friday and the National Hurricane Center designated the system at Tropical Storm Vicente.

The circulation around Tropical Storm Vicente is very small.  Winds to tropical storm force only extend out about 35 miles (55 km) from the center of circulation.  Vicente does have a well developed center and a ring of thunderstorms surrounds the center of circulation.  Several short bands of showers and thunderstorms were revolving around the core of Tropical Storm Vicente.  Storms around the core were generating upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Vicente will move through an environment mostly favorable for intensification.  Vicente will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Vicente is likely to strengthen during the next 24 to 36 hours.  Northerly winds blowing across the Isthmus of Tehuantepec will transport drier air over the Gulf of Tehuantepec.  If the drier air enters the circulation of Vicente, then the tropical storm could weaken.  Since the circulation around Tropical Storm Vicente is so small, the tropical storm could intensify or weaken very rapidly if the environmental conditions change.

Tropical Storm Vicente will move around a ridge of high pressure over the Gulf of Mexico and Mexico.  The ridge will steer Vicente in a general westerly direction during the weekend.  On its anticipated track Tropical Storm Vicente will stay south of Mexico during the next 24 to 48 hours.  Vicente could move more toward the northwest early next week when it moves around the western end of the ridge of high pressure.