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Preliminary Report
Hurricane Lester
15-26 October 1998

Miles B. Lawrence
National Hurricane Center
15 December 1998

Tropical Storm Agatha
Hurricane Blas
Tropical Storm Celia
Hurricane Darby
Hurricane Estelle
Tropical Storm Frank
Hurricane Georgette
Hurricane Howard
Hurricane Isis
Tropical Storm Javier
Hurricane Kay
Hurricane Lester
Hurricane Madeline

[1998 East Pacific Hurricane Season]

Lester moved close, and parallel to, the coast of Mexico for several days, but hurricane conditions remained offshore.

a. Synoptic History

The tropical wave responsible for the origination of Hurricane Lester left Africa on 29 September. This wave initiated the development of Hurricane Lisa in the tropical Atlantic Ocean on 5 October midway between Africa and the Lesser Antilles. The wave itself continued westward, moving across Central America on 11 and 12 October as a poorly-organized cluster of thunderstorms. A low-level circulation center was first observed on satellite imagery on the 13th, in the eastern Pacific Ocean about 150 n mi south of the border between El Salvador and Guatemala. This feature moved slowly northwestward as convection increased near the center and a banding feature formed. It is estimated that Tropical Depression Fourteen-E formed at 0000 UTC on 15 October while centered about 175 n mi south of the coast of Guatemala. This is the time of the beginning of the best-track of Hurricane Lester as shown in Fig. 1 (24K GIF) and listed in Table 1.

Lester's track generally paralleled the coast of Mexico from the 15th through the 20th. The track turned southwestward on the 22nd and northwestward on the 24th and dissipation occurred about 450 n mi southwest of the southern tip of the Baja Peninsula on the 26th. On the large scale, the motion is toward the west-northwest at 10 kt or less. This is consistent with the steering associated with a high pressure ridge which was located to the northeast or north during Lester's existence. On a shorter time scale, a short wave trough passed by to the north on the 17th, which slowed the forward motion to nearly stationary for several hours. Another short wave trough slowed the motion to nearly stationary again on the 22nd. A ridge then built to the north causing a motion toward the southwest for a day, followed by a resumption of a northwestward track.

The shape of the track closely resembles the shape of the coastline from the 15th through the 18th (Fig. 1). The track shape, along with its close proximity to the coast, may be coincidental. Mexico is a mountainous country and the effects of this land mass on the track and intensity of a tropical cyclone are not well known.

Lester's center moved to about 100 n mi south of the Guatemala and Mexico coasts on the 15th, while it was a tropical storm. Lester became a hurricane on the 16th and remained one until the 23rd. The closest point of approach of the center to the coast was about 60 n mi south of Puerto Angel, Mexico on the 17th and 18th. Its maximum 1-min surface wind speed reached 90 kt on the 17th and remained near that speed through the 22nd, when it briefly reached 100 knots. It is possible that tropical storm force winds and some heavy rainfall reached the coast between the Mexico/Guatemala border and Punta Maldonaldo. It is not believed that Lester was close enough for hurricane conditions to reach the coast.

b. Meteorological statistics

A U.S. Air Force reconnaissance aircraft flew into the center on the 17th and 18th. This was a test of international aviation clearance procedures. The highest wind speed reported by this aircraft was 98 kt at 700 mb on the 18th and the minimum central surface pressure was 973 mb.

Figs. 2 (23K GIF) and 3 (25K GIF) show plots of the best-track pressure and wind speed curves, along with the reconnaissance data mentioned above and Dvorak satellite intensity estimates. Subjective Dvorak estimates were provided by the U.S. Air Force Weather Agency (AFGWC), the Tropical Analysis and Forecast Branch (TAFB) of the Tropical Prediction Center, NWS and the Satellite Analysis Branch (SAB) of NESDIS. The maximum wind speed of 100 kt on the 22nd is based on satellite imagery showing a well-defined eye embedded in an area of cloud tops of -60 to -70C.

There have been no observations received of strong winds on the coast of Mexico.

A series of radar images from the Mexican National Meteorological Service radar at Puerto Angel showed the northern half of an eye wall remaining off shore on the 17th and 18th.

c. Casualty and damage statistics

There have been no reports received of casualties or damage.

d. Forecast and warning critique.

For the official track forecasts issued while Lester was a tropical storm or hurricane, the average track errors were 11, 32, 63, 94, 125, and 183 n mi, respectively for the 0-, 12-, 24-, 36-, 48-, and 72-h forecast periods. There were 41 forecast cases verified at the 0-h forecast, decreasing to 29 cases at 72 hours. These errors are slightly smaller than the corresponding 1988-1997 average official errors at all forecast periods.

There was a significant northward bias to the official track forecasts while Lester was near the coast of Mexico. Much of the model guidance also had this bias as a result of forecasting a short wave trough to erode the ridge to the north of the hurricane.

In the early stages, the official wind speed forecasts failed to capture the strengthening and 72-h wind speed forecast errors were as large as 65 knots.

The close proximity of the track to the coastline required the issuance of watches and warnings from Sipacate, Guatemala westward to Punta San Telmo, Mexico. Tropical storm warnings were issued east of Puerto Arista, Mexico and hurricanes warnings were issued to the west of Puerto Arista to Acapulco. A hurricane watch was issued west of Acapulco to Punta San Telmo. These actions occurred over the period from the 15th to the 19th and are listed in Table 2.

Table 1. Best track, Hurricane Lester, 15-26 October 1998.
Position Pressure
Wind Speed
Lat. (°N)Lon. (°W)
15/000011.391.7100530tropical depression
120012.392.1100530 "
180012.792.5100435tropical storm
180015.5109.799560tropical storm
26/000017.4115.1100530tropical depression
1800    dissipated
22/120016.8108.8965100minimum pressure

Table 2. Watches and warnings issued for Hurricane Lester, October 1998.
15/1500tropical storm warning Sipacate, Guatemala to Puerto Arista, Mexico
tropical storm watchwest of Puerto Arista to Puerto Angel, Mexico
16/0300tropical storm warning Puerto Arista to Punta Maldonaldo, Mexico
hurricane watchPuerto Arista to Punta Maldonaldo
16/0900hurricane warningPuerto Arista to Punta Maldonaldo
16/1500tropical storm warning discontinuedGuatemala
17/0900hurricane watch west of Punta Maldonaldo to Acapulco, Mexico
tropical storm warning discontinuedeast of Puerto Arista
17/2100hurricane warning Salina Cruz to Acapulco, Mexico
hurricane watchwest of Acapulco to Zihuatanejo, Mexico
hurricane warning discontinuedeast of Salina Cruz
19/0900hurricane warning discontinued Salina Cruz to Acapulco
hurricane watchZihuatanejo to Punta San Telmo, Mexico
19/2100hurricane watch discontinuedwest of Acapulco to Punta San Telmo

Jack Beven

Last updated May 28, 1999