From the Tropical Atlantic to the United States Virgin Islands and Puerto Rico
Shawn P. Bennett
Science and Operations Officer
National Weather Service
Weather Forecast Office
San Juan, Puerto Rico
Warning and Coordination Meteorologist
National Weather Service
Weather Forecast Office
San Juan, Puerto Rico
1.1 Historical Context
Hurricane Georges was the most destructive hurricane to strike the entire island of Puerto Rico since Hurricane San Ciprian in 1932. Hurricane Hugo which struck the U.S. Virgin Islands, Vieques, Culebra, and the eastern half of Puerto Rico in 1989 was also very destructive, leaving $3 billion in damage in its wake. In 1995, Hurricane Marilyn struck the U.S. Virgin Islands, Vieques, Culebra and the eastern section of Puerto Rico causing major devastation. Hurricane Marilyn caused over $2 billion in damage in the U.S. Virgin Islands alone. Georges tracked across the U.S. Virgin Islands, Vieques and Culebra, but unlike its predecessors Hugo and Marilyn its impact in these smaller islands was not as severe as in Puerto Rico. Among Hurricane Georges most remarkable characteristics was that it tracked through the islands of the Greater Antilles: Puerto Rico, Hispaniola (Dominican Republic and Haiti) and Cuba, before affecting the Florida Keys and southeastern Florida before finally ending its rampage on the coasts of SE Louisiana, Mississippi, Alabama, and northwest Florida (ref. Figure 1). Hurricane George affected the major population centers of the Caribbean: San Juan, Santo Domingo, Port-au-Prince, and Havana. Perhaps even more remarkable was its track across the entire length of Puerto Rico from east to west following the spine of the Central Mountain Range (ref. Figure 2). Hurricane San Ciprian in 1932 was the last storm to track on a generally east to west course across Puerto Rico.
2.1 Tropical Atlantic Ocean to the Northeastern Caribbean Sea
Tuesday, September 15th to Sunday, September 20th, 1998
The tropical weather system that was eventually to be named Georges emerged from the west African coast as a well-formed tropical wave and was classified as Tropical Depression 7 on Tuesday, September 15th at 11 am AST near 9.0N 25.9W or about 400 miles southwest of the Cape Verde Islands. Tropical Depression 7 quickly intensified and was classified as Tropical Storm Georges 24 hours later on Wednesday, September 16th at 11 AM AST near 10.0N 32.4W with a movement of west-northwest near 20 mph. On Thursday, September 17th at 5 PM AST Tropical Storm Georges became the fourth hurricane of the season near 12.5N 41.1W with a minimum central pressure of 987 mb and a movement of west-northwest at 20 mph. Hurricane Georges was then some 1300 miles east of the Lesser Antilles and moving quite fast. Over the next two days during its trek across the warm waters of the tropical Atlantic Ocean Hurricane Georges strengthened into the first Saffir-Simpson Scale Category 4 hurricane of the 1998 hurricane season. At 5 PM AST on Saturday, September 19th Hurricane Georges was first classified as a strong Category 4 hurricane based on reconnaissance aircraft wind and pressure measurements. A few hours later at 8 PM AST Hurricane Georges located near 15.8N 55.0W attained its lowest central pressure of 938 mb and its greatest intensity with sustained winds at 150 mph. Satellite images of Hurricane Georges showed an impressive storm with well-defined eye of about 35 miles in diameter. Figure 1 shows Georges as a Category 4 hurricane with a pinpoint eye on September 20th at 8:45 AM AST, when it was about 485 miles east-southeast of Christiansted, St. Croix and about 585 miles east-southeast of San Juan, Puerto Rico. As Hurricane Georges made its approach to the northeastern Caribbean Saturday night through Sunday evening it found unfavorable conditions and weakened from a Category 4 storm to a Category 3 then to a strong Category 2 storm with sustained winds of 110 mph as began to encounter some northwesterly vertical wind shear in the upper level wind field. Vertical wind shear is the variation of wind direction and speed with elevation in the atmosphere, an atmospheric condition unfavorable or hostile to tropical cyclone formation and development. In this case the vertical wind shear acted to first weaken Hurricane Georges from a strong Category 4 to strong Category 2 storm then inhibit further strengthening as it traversed the northern Leeward Islands. Figure 3 shows Hurricane George affecting the islands of Antigua, Barbuda, Nevis, St. Kitts, Saba, St. Martin, Anguilla, Guadeloupe, and Dominica on its path toward the U.S. Virgin Islands and Puerto Rico.
2.2 Northeastern Caribbean Sea: Northern Leeward Islands, U.S. Virgin Islands and Puerto Rico
Sunday, September 20th to Monday, September 21st, 1998
Hurricane Georges began affecting the northern Leeward Islands about 8 PM AST Sunday, September 20th as the center of circulation was located near 16.7N 60.6W or about 85 miles east-southeast of Antigua. The storm battered the northern Leeward Islands with sustained winds of 110 mph. An unofficial wind observation from Antigua reported winds at 94 mph with gusts to 116 mph. On the island of Saba another unofficial report of wind gusts to 175 mph was received, however this report was received late Monday due to communication problems at the site where it was recorded. By 8 AM AST Monday, September 21st Hurricane Georges was situated about 75 miles east of St. Croix near 17.5N 63.7W as the eye was passing about 45 miles south of St. Martin (ref. Figure 4).
By this time the center of the eye of the hurricane had moved out of the northern Leeward Island into the Caribbean Sea. By 12 noon AST Monday the eye of Georges was located near 17.8 North 64.5 West or about 20 miles east northeast of St. Croix. By 1 PM AST Monday the center of the eye of Hurricane Georges was situated just a few miles north of Christiansted, St. Croix near 17.9N 64.7W or about 70 miles east-southeast of San Juan, Puerto Rico. Reports from residents of St. Croix and Doppler radar data suggested that the west part of the eye wall started to enter St. Croix around 11:20 AM AST with northwest winds increasing to 95 mph with gusts to 113 mph at Maria Hill. The hurricane force winds associated with the west part of the eye wall lasted for about 25 minutes. Then the winds decreased with a period of relatively calm winds of near 25 mph around 12:30-12:45 PM AST. Around this time the lowest sea level pressure was recorded at St. Croix of 972.2 mb. Then the winds started to increase again but this time from the south reaching a peak gust of 110 mph at 2:27 PM AST. By 2 PM AST Georges was located near 17.8 N 64.9 W or about 35 miles southeast of Vieques. By 4 PM AST Monday Georges was located near 17.9 N 65.3 W or about 15 miles south of Vieques. Through the daylight hours on Monday Hurricane Georges began to gather strength through the combination of the warmer waters of the Caribbean Sea, the demise of the northwesterly vertical wind shear, and the unencumbered circulation of the winds about the eye as it moved from St. Croix, over the Puerto Rican island of Vieques toward landfall on the southeast coast of Puerto Rico. At 5:30 PM AST Monday Hurricane Georges was reclassified as a Category 3 hurricane on the Saffir-Simpson Scale. The reclassification to a Category 3 hurricane was based on reported wind observations of 110 mph sustained with gusts to 130 mph by Civil Defense in Fajardo on the east coast of Puerto Rico in combination with Doppler radar observations from the Weather Surveillance Radar 1988 Doppler (WSR-88D) situated on the ridgeline near Cayey in eastern Puerto Rico. At 6 PM AST the eye was located at 18.1N 65.7W just off the coast of southeastern Puerto Rico or 35 miles southeast of San Juan (ref. Figure 5).
Hurricane Georges made landfall at around 7 PM AST on Monday in the vicinity of Yabucoa-Humacao near 18.1N 66.0W in southeast Puerto Rico or 25 miles southeast of metropolitan San Juan with sustained winds of 115 mph and gusts to 150 mph and a minimum central pressure of 967 mb (ref. Figure 6). At that time the diameter of the eye was approximately 20-25 miles wide. Landfall is when the center of circulation or the center of the eye touches land.
2.3 Northeastern Caribbean Sea: Southeastern Puerto Rico to the Mona Passage:
Monday, September 21st to Tuesday, September 22nd, 1998
Hurricane Georges traversed the island of Puerto Rico from east to west, its eye as seen by Doppler weather radar, describing an oscillating motion, at times over the Central Mountain Range, and at other times to the south of the mountains. By 8 PM AST Monday the center of the eye of Georges was 20 miles southwest of the San Juan near 18.2N 66.2W, its closest approach to the island largest metropolitan area. Although the calm of the eye was not felt at the Luis Muñoz Marin International Airport, residents of other sections of the San Juan metropolitan area further inland did experience the calm winds. Between 8 PM AST and 9 PM AST Doppler weather radar imagery showed that an area of especially strong thunderstorms developed along the southeast section of the eyewall and affected the mountainous portions of the municipalities of Cayey, Aibonito, Coamo, Villaba, Juana Diaz, Barranquitas, Orocovis, Ciales, and Jayuya (ref. Figure 7).
The eyewall is the collection of very intense thunderstorms that merge together and form a vertical wall or barrier around the center of circulation - the eye. Very heavy rain fell (ref. Section 4.6) and tornadoes may have been spawn as this area of intense thunderstorms interacted with the mountainous terrain through the aforementioned municipalities (ref. Section 4.10). An hour later at 9 PM AST the center of the eye was located at 18.2N 66.4W in the vicinity of Orocovis at or about 15 miles southwest of San Juan. Two hours later at 11 PM AST the eye was located in the vicinity of Yauco-Sabana Grande near 18.1N 66.9W now some 30 miles west-southwest of San Juan. By 1 AM AST Tuesday, September 22nd the center of the eye of Hurricane Georges had left the island of Puerto Rico for the waters of the Mona Passage and was located near 18.1N 67.5W or about 25 miles west-southwest of Mayaguez still with sustained winds of 110 mph and occasional gusts to 150 mph, estimated minimum central pressure had risen to 978 mb. During its trek across Puerto Rico Hurricane Georges lashed furiously at the islands major population centers and rural areas indiscriminately with its estimated maximum sustained winds of up to 115 mph and gusts of 150 mph . With an eye of from 25 to 30 miles in diameter no part of the island went unscathed by the fury of Hurricane Georges. Throughout its unwanted visit to Puerto Rico Hurricane Georges moved generally westward near 15 mph, from its landfall on the southeast coast until it exited the island on the southwest coast and entered the Mona Passage.
3.1 NWS National Hurricane Center (NHC) Advisories, Watches, Warnings For The U.S. Virgin Islands and Puerto Rico
3.2 NWS Weather Forecast Office (WFO) San Juan Products and Services
Hurricane operations plan at the San Juan WFO began 72 hours in advance of the arrival of the hurricane. The initial similarities in the formation point and subsequent development of Georges in comparison with Hurricane Hugo of 1989 alerted the staff to potential impact of the system on our County Warning Area (CWA). The office began to alert government officials and the public of the potential of this hurricane, through the radio, television, and newspaper media, as well as via our office internet web page. Hurricane Georges Category 4 intensity caught the attention of everyone. Throughout the event the San Juan WFO provided continuous series of weather forecast products and services, including briefings and updates on Hurricane Georges for government officials, emergency managers, and the general public in both Puerto Rico and the U.S. Virgin Islands. The San Juan WFO provided the following number and types of products: 28 Hurricane Local Statements and 29 Non-Routine Products which included a Tornado Warning, several Flash Flood Advisories and Watches, a Flash Flood Statement, a Flood Warning, several Special Marine Weather Statements and Warnings, several Coastal Flood Watches, a Severe Thunderstorm Warning, and a Severe Weather Statement. Refer to Appendix B for a complete list of the products issued.
4.1 Meteorological Observations
Listed below are meteorological observations collected from officially certified and unofficial cooperative observer sites in Puerto Rico and the U.S. Virgin Islands by the National Weather Service in San Juan.
4.2 Observed Maximum Winds from Official Observation Sites
Carolina (SJU) Luis Munoz Marin International Airport Automatic Surface Observing System (ASOS)
Sustained Wind: 69 kt (79 mph) from 050 degrees at 7:24 PM AST on Sept. 21st
Peak Gust: 81 kt (93 mph) from 070 degrees at 7:18 PM AST on Sept. 21st
Ceiba (TJNR) U.S. Naval Station Roosevelt Roads (ASOS)
Sustained Wind: 78 kt (90 mph) from 150 degrees at 7:02 PM AST on Sept. 21st
Peak Gust: 93 kt (107 mph) from 150 degrees at 6:49 PM AST on Sept. 21st
St. Thomas, U.S. Virgin Islands Cyril E. King Airport (ASOS)
Sustained Wind: 66 kt (76 mph) from 110 degrees at 4:31 PM AST on Sept. 21st
Peak Gust: 81 kt (93 mph) from 110 degrees at 4:36 PM AST on Sept. 21st
St Croix Airport, U.S. Virgin Islands Hamilton Airport (ASOS)
Sustained Wind: 64 kt (74 mph) from 190 degrees at 2:43 PM AST on Sept. 21st
Peak Gust: 79 kt (91 mph) from 190 degrees at 2:42 PM AST on Sept. 21st
VITEMA at Hermon Hill, St Croix, U.S. Virgin Islands, NWS Wind Sensor F420C Equipment
Sustained Wind: 71 kt (82 mph) at 2:15 PM AST on Sept. 21st
Peak Wind: 81 kt (93 mph) at 2:16 PM AST on Sept. 21st
4.3 Observed Maximum Winds from Unofficial Observation Sites
Cooperative Observer at Quebradillas, Puerto Rico (site elevation 440 feet)
Sustained Wind: 78 kt (90 mph) from 032 degrees at 10:45 PM AST on Sept. 21st
Peak Gust: 85 kt (98 mph) from 040 degrees at 10:44 PM AST on Sept. 21st
Cooperative Observer at Maria Hill, St. Croix, U.S. Virgin Islands (site elevation 340 feet)
Sustained Wind: 83 kt (95 mph) from 338 degrees at 11:35 AM AST on Sept. 21st
Peak Gust: 98 kt (113 mph) from 338 degrees at 11:34 AM AST on Sept. 21st
Peak Gust: 96 kt (110 mph) from 180 degrees at 2:27 PM AST on Sept. 21st
Cooperative Observer at Rincon, Puerto Rico
Sustained Wind: est. 87 kt (100 mph) from 090 degrees at 12:45 AM AST on Sept. 22nd
Peak Gust: est. 113 kt (130 mph) from 090 degrees at 12:45 AM AST on Sept. 22nd
4.4 Observed Lowest Atmospheric Pressure from Official Observation Sites
Carolina (SJU) ASOS 979.7 mb at 7:11 PM AST on Sept. 21st
Ceiba (TJNR) ASOS 971.4 mb at 5:45 PM AST on Sept. 21st
U.S. Virgin Islands
St. Thomas ASOS 991 mb at 3:43 PM and 4:12 PM on Sept. 21st
St. Croix ASOS 976 mb at 1:02 PM through 1:24 PM on Sept. 21st
4.5 Observed Lowest Atmospheric Pressure from Unofficial Observation Sites
Cooperative Observer at Quebradillas,
Puerto Rico 978.4 mb at 11:00 PM AST on Sept. 21st
Cooperative Observer at Maria Hill, St. Croix,
U.S. Virgin Islands 972.2 mb at 12:21 PM AST on Sept. 21st
Cooperative Observer at Rincon,
Puerto Rico 983 mb at 12:45 AM AST on Sept. 22nd
4.6 Observed 24 hour Rainfall (inches) from Official Observation Sites
September 21st (0000-2400) and September 22nd (0000-2400) and two-day Storm Total
Sept. 21st / Sept. 22nd / Two-day Storm Total
Carolina (WFO SJU)
4.32 / 0.94 / 5.26
St. Thomas Airport
4.31 / 0.68 / 4.99
St. Croix Airport
6.48 / 0.31 / 6.79
U.S. Geological Survey (USGS) Gages in Puerto Rico
Lago El Guineo at Damsite Near Villalba
9.79 / 14.83 / 24.62
Rio Saliente at Coabey Northeast of Jayuya
7.59 / 16.71 / 24.30
Rio Portuguez at Tibes
4.31 / 14.15 / 18.46
Quebrada Salvatierra Near San Lorenzo
10.42 / 6.51 / 16.93
Rio Grande De Arecibo Above Utuado
3.88 / 12.99 / 16.87
Lago Garzas Near Adjuntas
3.90 / 9.59 / 13.49
River Espiritu Santo Near Rio Grande
10.02 / 3.02 / 13.04
U.S. Geological Survey (USGS) Gages in the U.S. Virgin Islands
Bonne Resolution Gut in St. Thomas
4.13 / 1.89 / 7.91
National Park Service in St. Thomas
5.41 / 0.29 / 5.70
Guinea Gut at Bethany in St. John
3.05 / 0.36 / 3.41
Jolly Hill in St. Croix
6.84 / 0.57 / 7.41
A preliminary rainfall accumulation analysis was done by the U.S. Geological Survey office in Puerto Rico (image below). This analysis shows that the greatest rainfall accumulations occurred in the central interior mountains.
4.7 Storm Tides and Surge
Preliminary information from the USGS indicated storm surge values of 10 ft at Fajardo, Puerto Rico.
4.8 Beach Erosion
Erosion was severe in many places. Communities in western Puerto Rico were cut off because roadways were washed out to sea.
Flooding was extensive and serious, especially in the interior mountainous sections of Puerto Rico. At one time during the height of the storm all the rivers in Puerto Rico were reported out of their banks to some degree or another. Several bridges collapsed in interior, southeastern, and northern sections of Puerto Rico. The USGS reported that several rivers set new all-time discharge records. Many rivers carved out new channels as the record discharge swept downstream with tremendous force eroding entirely new parts of the flood plain and leaving many areas covered by standing water.
Three possible tornadoes were detected by the Doppler weather radar. One was detected about two miles north of Punta Este in Vieques at 4:29 PM AST. A second was detected near Orocovis and Barranquitas at 9:00 PM AST. The third was detected by Doppler weather radar in southeast sections of Jayuya. During an areal survey over Jayuya a damage pattern was observed east of town that was indicative of a tornado track through that part of town. The ground keeper at the Punta Santiago government owned villas in Humacao reported a tornado on the ground around 8:00 PM AST on Sept. 21st .
The information contained in this section was collected from official government sources, news clips and from eyewitness observations made during storm damage survey done by NWS personnel.
5.1 Preliminary Storm Effects in Puerto Rico
At the time of this report there were no deaths directly related to the hurricane based on official reports from the Commonwealth Forensic Institute.
Utility and Transportation Infrastructure
Damage to the islands utility infrastructure was enormous. Electricity was lost to 96% of the island 1.3 million customers, while water and sewer service was lost to 75% of the islands 1.83 million customers. It was estimated that at least 50% of the electrical poles and cables were damaged. Many roads were impassable by floods or destruction. A large number of road signs were twisted and destroyed, while electric post and cables were strewn on the ground, along with trees and foliage. Damage to roads was estimated at $21, 995,975. Telephone service was affected as 8.4% of telephone customers lost their service.
Agricultural and Business Sector
The hurricane caused a catastrophic blow to the agricultural sector. The island lost 75%of its coffee crop, 95% of the plantain and banana crops, and 65% of its live poultry. Loss to equipment, manufacturing, and agriculture was estimated at $212.9 million daily.
Housing and Public School Damage
Damage to houses was significant, especially those constructed of wood with metal roofs. In all 28,005 house were totally destroyed and 72, 605 houses of all type were partially destroyed. On the small island of Culebra, 74 houses were totally destroyed and 89 were partially damaged. Public schools suffered an estimated $20-$25 million dollars in damage.
All of the islands 401 shelters were opened during the storm and housed 29, 107 people.
Preliminary Damage Assessment
An estimated $1,673,529,890 in damages was caused to municipalities and $233,496,484 in damages to commonwealth agencies. Thus, the total damage in Puerto Rico was estimated at $1,907,026,374.
5.2 Preliminary Storm Effect in the U.S. Virgin Islands
No major damage was reported. In general it was described as minor. In St. Croix most of the damage was confined to the landscape, trees were uprooted throughout the island, some utility poles broke and power lines snapped. Port Authority officials indicated 55 boats were beached or sunk by the hurricane, 35 on St. Thomas, 5 on St. Croix and 15 on St. John. The bulk of the damage was to two St. Croix communities, the Paradise Mills Apartment Complex and the Estate Adventure Housing Complex, where at least three residences lost their roof. At Castle Burke trailer park of more than 100 trailers, only one was completely demolished. Preliminary estimates indicated about $2 million in damages territory-wide. Damages to St. Thomas public schools ranged from minor water leakage to major structural damage. On St. Thomas, the Estate Ross and Queen Louise Apartments housing complexes sustained minimal structural damage. On St. Croix the electrical infrastructure suffered more damage than in St. Thomas or St. John.
First and foremost we wish to acknowledge the selfless hard work and dedication that the staff of the San Juan WFO gave during Hurricane Georges. Thanks go to Dr. Jose Colon, former Meteorologist-in-Charge, Israel Matos, current Meteorologist-in-Charge and Ron Block, Senior Forecaster for their assistance in providing storm related data and information and for providing constructive comments which helped to improve this report. This report is dedicated to the people of Puerto Rico and the U.S. Virgin Islands who have suffered so much as a result of Hurricane Georges.
* Corresponding author address: Shawn Bennett or Rafael Mojica,
National Weather Service, 4000 Road 190, Carolina, PR 00979