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Preliminary Report
Hurricane Bret
18-25 August 1999

Miles B. Lawrence and Todd B. Kimberlain
National Hurricane Center
Revised 26 February 2001

Tropical Storm Arlene
Tropical Depression Two
Hurricane Bret
Hurricane Cindy
Hurricane Dennis
Tropical Storm Emily
Tropical Depression Seven
Hurricane Floyd
Hurricane Gert
Tropical Storm Harvey
Tropical Depression Eleven
Tropical Depression Twelve
Hurricane Irene
Hurricane Jose
Tropical Storm Katrina
Hurricane Lenny

[1999 Atlantic Hurricane Season]

Bret was a small hurricane that made landfall along a sparsely-populated section of the south Texas coast with sustained winds up to 100 knots. Bret was the first hurricane to strike the Texas coast since Hurricane Jerry in October 1989. It was the first hurricane to affect south Texas since Hurricane Allen in August 1980, and it was the strongest since Hurricane Alicia in 1983.

a. Synoptic History

Bret formed as a tropical depression over the Bay of Campeche on 18 August. Both a tropical wave and an upper-level low contributed to the formation of Bret. A tropical wave moved from Africa to the tropical Atlantic Ocean on 5 August. Continuity and soundings from Merida, Mexico place this weak tropical wave in the vicinity of the Yucatan Peninsula on the 18th. The second feature, an upper-level cyclonic circulation, appeared on water vapor imagery over the north central Caribbean moving westward on 15 August. The circulation initiated a thunderstorm complex on the night of the 17th over the Yucatan Peninsula and a weak surface low formed in the same location early on the 18th..

Later on the 18th, the surface low moved over the Bay of Campeche. Early morning visible satellite imagery showed a low level cloud circulation center and, a few hours later, a U.S. Air Force Reserve Unit reconnaissance mission confirmed the existence of a closed circulation. With some deep convection and banding present, the system was upgraded to a tropical depression at 1800 UTC on the 18th over the Bay of Campeche. The best track begins at this time, as shown in Table 1, which is a listing of Bret's best track positions, wind speeds, and central pressures, every six hours. Figure 1 shows a map of this track.

The depression did not strengthen right away due to vertical shear caused by an upper-level trough over the extreme western Gulf of Mexico. But the trough moved away and Bret reached tropical storm strength late on the 19th while beginning to move slowly northward. The vertical shear decreased. Bret rapidly became more organized and then steadily strengthened to a 125-knot category four hurricane on the Saffir/Simpson scale on the morning of the 22nd, while appproaching south Texas coast near Brownsville. Responding to the presence of a weak mid-tropospheric ridge over the northwest Gulf of Mexico and to a mid-tropospheric cyclonic circulation over the Rio Grande valley, Bret turned northwestward and slowed its forward speed down to about 5 knots. The forward speed had earlier been as high as 9 knots.

Bret's center crossed the Texas coast over the central portion of Padre Island, midway between Brownsville and Corpus Christi, at 0000 UTC, 23 August. It had weakened to a category three hurricane with 100 knot winds and a pressure of 951mb by the time of landfall. After moving inland, Bret's movement became more westward with a slow forward speed. Bret continued to weaken as it moved across south Texas and into the high terrain of north central Mexico where it dissipated on the 25th.

b. Meteorological Statistics

Figure 2 and Figure 3 depict the best track curves and data plots of the maximum sustained 1-min surface winds (10m above ground level) and minimum central pressure, respectively, as a function of time. These plots include data gathered by aircraft reconnaissance and Dvorak satellite classification estimates and an occasional ship or land report.

Aircraft reconnaissance coverage began at 2000 UTC 18 August and continued until just after the hurricane's landfall at 0100 UTC 23 August. The maximum 1-min surface wind speed of 125 knots at 0600 and 1200 UTC on the 22nd is based on GPS-sonde vertical wind speed profiles. Figure 4 shows one of these profiles and shows that winds reached near 150 knots within 1000 feet (300 meters) above the surface and were near 125 knots near the surface. Bret's pressure dropped 35 millibars to 944 millibars in the 24 hours ending at 1200 UTC on the 22nd and dropped 21 millibars in the six hours ending at 0000 UTC of the same day.

This episode of intensification coincides with the hurricane's track over a maximum in the sea surface temperature (SST) field over the west central Gulf of Mexico. Analyses from the Johns Hopkins University Applied Physics Laboratory shows 31C SST values along Bret's track during this intensification period. In addition, estimates of the upper oceanic heat content (described by Shay et al., 1999) under portions of the hurricane's circulation in the western Gulf of Mexico were rather high.

During the 12 hours prior to landfall, the hurricane weakened from 125 to 100 knots. It was also at this time that the western edge of the eyewall was coming into contact with Padre Island.

Bret was a small hurricane. At its peak, hurricane force winds were confined to a narrow radius of 30-40 miles from the center in the north semicircle and only 10-20 miles in the south semicircle. Thus only a small segment of the Texas coast was affected by the core of the hurricane. Kennedy County received most of the hurricane force winds which are estimated as high as 100 knots over a small portion of the coast of Padre Island. With the center moving inland over a sparsely populated area, few surface reports were available substantiating strong winds. Table 2 lists a selection of available surface observations, provided by the National Weather Service offices at Brownsville, Corpus Christi, and Houston/Galveston. The highest reported sustained wind in Table 2 is 63 knots at Rincon del San Jose on Padre Island. The instrument there failed at 2230 UTC on the 22nd just before the center passed close by.

The Port Aransas C-MAN station reported maximum sustained winds of 41 knots as the center of the hurricane passed about 60 n mi to the south.

Bret was slow moving and Doppler radar estimates suggest maximum storm total precipitation amounts of over 30 inches in Kennedy county. None of the rainfall totals in Table 2 come close to that value. Aransas Pass is north of the area of peak rainfall and it reported a storm total of 12.60 inches. The heavy rains accompanying the weakening tropical cyclone caused notable river flooding in the Rio Grande Valley. The Rio Grande River at Laredo and the Aransas River near Skidmore and at Oso Creek crested slightly above flood stage, causing local flooding in these respective areas.

A 24-hour rainfall total of over 14 inches was reported from the Mexican state of Nuevo Leon and the state of Tamaulipas is believed to have received similar rainfall.

Theoretical values from the SLOSH storm surge model indicate that a narrow region along Central and North Padre Island had a storm surge of 8 to 10 feet. A report from Port Mansfield Pass suggests that three to five feet of water penetrated this coastal location. Several cuts were observed in the dunes surrounding Padre Island. The largest of these, near mile marker 50 near the eye's passage, was mistaken by aircrews inspecting the damage as the Mansfield Pass. Substantial beach erosion was reported near Port Mansfield.

In Aransas County around 2145 UTC 22 August, a tornado reportedly destroyed a recreational vehicle, along with a barn and a shed, and uprooted trees. Other reports indicate that a tornado touched down in Kingsville around 2245 UTC on the 22nd and a tornado was reported in Alice, time unknown. Little damage was reported with the latter two.

c. Casualty and Damage Statistics

Despite Bret's intensity, damage was generally reported to be fairly light. Much of this owed to its landfall over a sparsely populated region in south Texas and its small size. The nearest population centers, Brownsville and Corpus Christi, were spared the brunt of the hurricane's core.

Property insurance damage claims total 30 million dollars as reported by the Property Claims Services Division of the Insurance Services Office. Multiplying by a factor of 2.0 gives an estimated damage total of 60 million dollars.

There have been no reports of loss of life.

d. Forecast and Warning Critique

The average forecast track errors for Bret are as follows: 65 n mi at 24 hours, 155 n mi at 48 hours, and 255 n mi (5 cases) at 72 hours. These values are just slightly below the previous 10-year averages. The GFDL model had a left bias and brought the hurricane inland over Mexico on a northwest to westward track for several forecasts as Bret moved northward. It has been suggested that the use of high-resolution topography with 18,000-feet mountains over Mexico in the GFDL model is the reason for the left bias.

The official forecast issued at 1800 UTC on the 19th, when Bret first became a tropical storm, had a 72-hour wind speed error of -85 knots. This was caused by the GFDL bias and resultant official forecast which placed the storm inland in 72 hours, rather than strengthening in the Gulf of Mexico.


Shay, L. K., G. J. Gustavo, J. Goni, and P. G. Black, 1999: Effects of a warm oceanic feature on Huricane Opal. Accepted for publication in Mon.Wea.Rev.

Figure 1. Best track positions for Hurricane Bret, 18-25 August 1999.

Figure 2. Best track maximum sustained wind speed curve for Hurricane Bret.

Figure 3. Best track minimum central pressure curve for Hurricane Bret.

Figure 4. GPS Dropsonde vertical wind speed profile for Hurricane Bret.

Table 1. Preliminary Best Track - Hurricane Bret, 18-25 August, 1999.
Position Pressure
Wind Speed
Lat. (°N)Lon. (°W)
18/180019.594.4101030tropical depression
19/000019.594.5 1008 30"
180019.894.7100535tropical storm
120027.398.398060tropical storm
24/000028.099.5100030tropical depression
0600 dissipated
22/120026.296.1944125minimum pressure
23/000026.997.4951100landfall at central Padre Island, Texas

Table 2. Hurricane Bret selected surface observations, August 1999.
Maximum surface wind speed
Location Press.
gust (kts)
(storm total)
Brownsville Airport ASOS1002.422/2131294722/1830  1.99
Cameron City Airport ASOS999.722/2035364622/1841  3.49
Harlingen Airport ASOS999.022/2310384822/2208  2.55
Port Isabel     1.1  
McAllen Airport ASOS1003.123/0023283722/2209  2.93
South Padre Island998.622/1815384822/1915  3.88
Arroyo Colorado  435722/1900   
Port Mansfield985.422/2000426622/2200   
Rincon del San Jose  63*78*22/2230   
Falfurrias Airport976.622/0330 85*23/0330   
Edinburg       3.41
El Sauz       2.00
Falcon       1.19
Garciasville       2.72
Harlingen       2.94
Hebbronville       4.57
Laguna Atascosa       4.16
La Joya       4.65
Los Fresnos       2.56
McAllen       3.10
Mercedes       1.02
Monte Alto       4.06
Rancho Viejo       1.45
Raymondville       3.07
Rincon       1.80#
Rio Grande City       4.14
Santa Ana NWR       3.82
Santa Rosa       3.54
Sarita(Kenedy Co.) County co        13.18
Weslaco       6.84
Zapata       2.48
Bob Hall Pier      2,6 
Corpus Christi1002.423/0322394823/0326  5.18
Kingsville NAS ASOS1001.7 35 4422/1843  3.09
Rockport ASOS1006.422/2228344123/1506 1.82.29
Victoria ASOS1008.823/0900222824/1811  0.69
Alice ASOS998.323/1217394823/1748  3.97
Cotulla ASOS1006.423/1753334023/2332  4.27
McMullen Target ASOS  38 22/2124   
Port Aransas C-MAN1003.122/2200415223/2200   
Aransas Pass   5723/2115  12.60
Freer       2.68
Benavides       5.10
Calliham       2.00
Concepcion       7.38#
Fowlerton       4.07
George West       5.30
Point Comfort       0.21#
Portland       7.95
Robstown       5.36#
Sinton       5.46
Victoria CP&L       0.52
Alice       3.00
Buoy 420191007.22/220037 23/1600   
Buoy 42020982.922/1900587322/1900   
Freeport      2.4 
Palacios ASOS1008.23/0353232722/1012  0.42
Galveston ASOS1010.23/0425192223/1032  0.02
Angleton/L. Jackson ASOS1010.23/06022026   0.26

aNWS ASOS and C-MAN averaging periods are 2 min; buoys are 8 min.
bDate/time is for sustained wind when both sustained and gust are listed.
cStorm surge is water height above normal astronomical tide level.
dStorm tide is water height above NGVD.
*Equipment failed or power outage experienced.
#24-hour rainfall total.

Table 3. Watch and warning summary, Hurricane Bret, 18-25 August, 1999.
Action Location
19/2100Tropical Storm Warning issuedTampico to Coatzacoalcos, Mexico
20/1500Hurricane Watch and Tropical Storm Warning issuedLa Pesca to Veracruz, Mexico
20/1500Tropical Storm Warning discontinuedVeracruz to Coatzacoalcos, Mexico
21/0900Hurricane Watch issuedTuxpan, Mexico to Baffin Bay Texas
21/0900Hurricane Watch/Tropical Storm Warning discontinuedTuxpan to Vera Cruz, Mexico
21/1500Hurricane Warning issuedLa Pesca, Mexico to Baffin Bay, Texas
21/2100Hurricane Watch/Tropical Storm Warning issuedBaffin Bay to Port Aransas, Texas
22/0300Hurricane Warning issuedBaffin Bay to Port O'Connor, Texas
22/0300Hurricane Watch/Tropical Storm Warning issuedPort O'Connor to Freeport, Texas
22/0900Hurricane Watch discontinuedTuxpan to Tampico, Mexico
22/1500Hurricane Watch discontinuedTampico to La Pesca, Mexico
22/2100Hurricane Watch discontinuedPort O'Connor to Freeport, Texas
23/0100Hurricane Warning discontinuedLa Pesca to U.S./Mexican border
23/0300Hurricane Warning downgraded to Tropical Storm Warningnorth of Port Aransas to Port O'Connor, Texas
23/0300Tropical Storm Warning discontinuednorth of Port O'Connor to Freeport, Texas
23/0900Hurricane Warning downgraded to Tropical Storm WarningBrownsville to Port Aransas, Texas
23/2100Tropical Storm Warning discontinuedBrownsville to Port Aransas, Texas


Last updated February 27, 2001