Skip Navigation Links weather.gov   
NOAA logo - Click to go to the NOAA homepage National Weather Service   NWS logo - Click to go to the NWS homepage
National Hurricane Center
Local forecast by
"City, St" or "ZIP"

 
Tropical Cyclones
   Alma
   Boris
   Three-E
   Cristina
   Douglas
   Elida
   Seven-E
   Fausto
   Genevieve
   Hernan
   Eleven-E
   Iselle
   Julio
   Kenna
   Lowell
   Sixteen-E
Get Storm Info
   Satellite | Radar
   Aircraft Recon
   Advisory Archive
   Experimental
   Mobile Products
   E-mail Advisories
   Audio/Podcasts
   GIS Data | RSS XML/RSS logo
   Help with Advisories
Marine Forecasts
   Atlantic and E Pacific
   Forecast and
   Analysis Tools

   Help with Marine
Hurricane Awareness
   Be Prepared | Learn
   Frequent Questions
   AOML Research
   Hurricane Hunters
   Saffir-Simpson Scale
   Forecasting Models
   Eyewall Wind Profiles
   Glossary/Acronyms
   Storm Names
   Breakpoints
Hurricane History
   Seasons Archive
   Forecast Accuracy
   Climatology
   Most Extreme
About the NHC
   Mission and Vision
   Personnel | Visitors
   NHC Virtual Tour
   Library
   Joint Hurr Testbed
   The NCEP Centers
Contact UsHelp
FirstGov.gov is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.

Tropical Cyclone Report

Tropical Storm Genevieve

26 August - 1 September 2002

Lixion A. Avila
National Hurricane Center
12 October 2002

Tropical Storm Genevieve formed south of Baja California and soon moved over cool waters.

a. Synoptic History

A tropical wave crossed Dakar, Senegal on 13 August. The wave was accompanied by a large area of thunderstorms with a well-defined low-level cyclonic wind-shift and a column of high moisture that extended from the surface to near 400 mb. As the wave moved westward, it lost most of its associated convection, and it was not until the system was south of Hispaniola on the 19th that the thunderstorm activity partially regenerated. Thereafter, the wave continued westward with a gradual increase in organization and crossed Central America where developed a distinct mid-level circulation. A tropical depression formed at 0000 UTC 26 August about 500 n mi south of the southern tip of Baja California and became a tropical storm 24 hours later. Genevieve was near hurricane strength with maximum winds of 60 knots and a minimum pressure of 989 mb at 0000 UTC 28 August when it turned to the northwest toward cooler waters and convection began to weaken. It was dissipating about 960 n mi west-northwest of the southern tip of Baja California at 0600 UTC 1 September. A swirl of low clouds associated with Genevieve's remnants persisted for a couple of days.

The "best track" chart of Genevieve's path is given in Figure 1 with the wind and pressure histories shown in Figure 2 and Figure 3, respectively. The best track positions and intensities are listed in Table 1.

a. Meteorological Statistics

Observations in Genevieve (Figure 2 and Figure 3) include satellite-based Dvorak technique intensity estimates from the Tropical Analysis and Forecast Branch (TAFB), the Satellite Analysis Branch (SAB) and the U. S. Air Force Weather Agency (AFWA). Infrared satellite estimates from TAFB and SAB indicated that Genevieve was a hurricane by 1200 UTC 28 August. However, visible satellite images a couple of hours later showed a disrupted cloud pattern indicating that the T-numbers were overestimated and Genevieve was not a hurricane.

c. Casualty and Damage Statistics

There were no reports of damage or casualties associated with Genevieve.

d. Forecast and Warning Critique

Average official track errors (with the number of cases in parentheses) for Genevieve were 36 (12), 63 (10), 74 (8), 85 (6), and 142 (2) n mi for the 12, 24, 36, 48, and 72 h forecasts, respectively. With the exception of the 12 and 24 hour periods, these errors are much lower than the average official track errors for the 10-yr period 1992-2001 of 36, 67, 97, 125, and 182 n mi, respectively). However, several of the numerical track guidance produced even lower errors than the official forecast at all times as indicated in Table 2.

Average official intensity errors were 7, 15, 17, 22, and 30 kt for the 12, 24, 36, 48, and 72 h forecasts, respectively. For comparison, the average official intensity errors over the 10-yr period 1992-2001 are 7, 12, 16, 18, and 21 kt, respectively.



Table 1: Best track for Genevieve, 26 August- 1 September, 2002.
Date/Time
(UTC)
PositionPressure
(mb)
Wind Speed
(kt)
Stage
Lat.
(°N)
Lon.
(°W)
26 / 000014.7110.4100730tropical depression
26 / 060014.5111.2100830"
26 / 120014.4112.0100730"
26 / 180014.2112.7100630"
27 / 000014.0113.2100535tropical storm
27 / 060013.9113.7100240"
27 / 120013.9114.399450"
27 / 180014.1114.999060"
28 / 000014.6115.598960"
28 / 060015.2116.198960"
28 / 120015.9116.998960"
28 / 180016.4117.998960"
29 / 000016.9118.999260"
29 / 060017.5119.699455"
29 / 120018.0120.1100245"
29 / 180018.5120.8100240"
30 / 000019.1121.5100535"
30 / 060019.6122.1100535"
30 / 120020.2122.7100730tropical depression
30 / 180020.8123.4100730"
31 / 000021.4124.1100925"
31 / 060022.3124.9100925"
31 / 120023.3125.1100925"
31 / 180024.1125.6100825"
01 / 000024.5126.5100920"
01 / 060024.9127.0100920dissipating
28 / 000014.6115.598960minimum pressure


Table 2: Preliminary forecast evaluation (heterogeneous sample) for Genevieve, 26 August 1 September, 2002. Forecast errors for tropical storm and hurricane stages (n mi) are followed by the number of forecasts in parentheses. Errors smaller than the NHC official forecast are shown in bold-face type.
Forecast TechniquePeriod (hours)
1224364872
CLP536 (12)71 (10)101 ( 8)146 ( 6)182 ( 2)
GFDI29 (12)66 (10)112 ( 8)147 ( 6)190 ( 2)
GFDL23 (11)47 (10)83 ( 8)116 ( 6)131 ( 2)
LBAR33 (12)57 (10)73 ( 8)75 ( 6)74 ( 2)
AVNI40 (12)73 (10)96 ( 8)115 ( 6)242 ( 2)
AVNO55 (12)83 (10)87 ( 8)87 ( 6)184 ( 2)
AEMI34 ( 9)64 ( 7)89 ( 6)130 ( 4)216 ( 1)
BAMD34 (12)54 (10)70 ( 8)56 ( 6)72 ( 2)
BAMM32 (12)55 (10)68 ( 8)71 ( 6)88 ( 2)
BAMS36 (12)72 (10)97 ( 8)134 ( 6)188 ( 2)
NGPI27 (12)46 (10)47 ( 8)65 ( 6)148 ( 2)
NGPS35 (10)56 ( 8)54 ( 7)58 ( 6)90 ( 2)
UKMI34 (11)64 ( 9)87 ( 8)78 ( 6)101 ( 2)
UKM36 ( 6)68 ( 5)84 ( 4)82 ( 3)18 ( 1)
GUNS25 (11)54 ( 9)72 ( 8)73 ( 6)88 ( 2)
GUNA24 (11)51 ( 9)69 ( 8)75 ( 6)105 ( 2)
OFCL36 (12)63 (10)74 ( 8)85 ( 6)142 ( 2)
NHC Official (1992-2001 mean)36 (2203)67 (1947)97 (1700)125 (1472)182 (1091)
*Output from these models was unavailable at time of forecast issuance.

Best track positions for Tropical Storm Genevieve

Figure 1: Best track positions for Tropical Storm Genevieve, 26 August- 1 September, 2002.

Selected wind observations and best track maximum sustained surface wind speed curve for Tropical Storm Genevieve

Figure 2: Selected wind observations and best track maximum sustained surface wind speed curve for Tropical Storm Genevieve, 26 August- 1 September, 2002.

Selected pressure observations and best track minimum central pressure curve for Tropical Storm Genevieve

Figure 3: Selected pressure observations and best track minimum central pressure curve for Tropical Storm Genevieve, 26 August-1 September, 2002.



Quick Navigation Links:
NHC Active Storms  -  Atlantic and E Pacific Marine  -  Storm Archives
Hurricane Awareness  -  How to Prepare  -  About NHC  -  Contact Us

NOAA/ National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
Tropical Prediction Center
11691 SW 17th Street
Miami, Florida 33165-2149 USA
nhcwebmaster@noaa.gov
Disclaimer
Credits
Information Quality
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities
Page last modified: Wednesday, 14-Feb-2007 13:27:19 GMT