Tropical Cyclone Report

Tropical Storm Odile

(EP0162008)

8-12 October 2008

John L. Beven II

National Hurricane Center

19 November 2008

Odile was a tropical storm that moved parallel to and just offshore of
the west coast of Mexico.

a.  Synoptic History

    Odile had a complex origin. A tropical wave moved westward from the
    coast of Africa on 23 September. This wave merged with another area
    of vorticity over the tropical Atlantic on 26 September, with the
    combined system continuing westward. The wave reached the western
    Caribbean on 4 October, where it merged with the southern end of an
    old frontal system. The northern end of this combination moved
    west-northwestward across the Yucatan Peninsula into the Bay of
    Campeche, where it contributed to the formation of Atlantic Tropical
    Storm Marco.

    The southern end of the system moved westward into the eastern
    Pacific and almost immediately showed signs of organization.
    However, the development was stopped by easterly vertical wind shear
    as the system stalled south of El Salvador on 5 October. There was
    little motion or change in organization during the next couple of
    days. Early on 8 October, another tropical wave moved into the
    eastern Pacific and approached the disturbance. Development resumed
    at that time, and it is estimated that a tropical depression formed
    at 1200 UTC that day about 105 n mi south-southwest of San Salvador,
    El Salvador. The "best track" chart of the tropical cyclone's path
    is given in Fig. 1, with the wind and pressure histories shown in
    Figs. 2 and 3, respectively. The best track positions and
    intensities are listed in Table 1[^1].

    A large mid- to upper-level ridge over Mexico steered the depression
    west-northwestward as it formed, with the center passing south of
    the Gulf of Tehuantepec as the system became a tropical storm on 9
    October. A northwestward turn on 10 October was followed by a
    resumed west-northwestward motion on 11 October. This resulted in
    the center moving parallel to the coast of Mexico about 40 n mi
    offshore. Odile reached an estimated peak intensity of 50 kt on
    10-11 October. After that, increasing southeasterly vertical wind
    shear caused rapid weakening. The cyclone became a tropical
    depression early on 12 October and subsequently decayed into a
    remnant low early on 13 October about 45 n mi south of Manzanillo,
    Mexico. The low moved slowly south-southwestward before dissipating
    later that day.

b.  Meteorological Statistics

    Observations in Odile (Figs. 2 and 3) include satellite-based Dvorak
    technique intensity estimates from the Tropical Analysis and
    Forecast Branch (TAFB) and the Satellite Analysis Branch (SAB), as
    well as flight-level, stepped frequency microwave radiometer (SFMR),
    and dropwindsonde observations from one flight of the 53^rd^ Weather
    Reconnaissance Squadron of the U. S. Air Force Reserve Command. Data
    and imagery from NOAA polar-orbiting satellites, the NASA Tropical
    Rainfall Measuring Mission (TRMM), the NASA QuikSCAT, and Defense
    Meteorological Satellite Program (DMSP) satellites, among others,
    were also useful in tracking Odile.

    The maximum intensity of Odile is somewhat speculative. Dvorak
    satellite intensity estimates were 55 kt from 0600-1800 UTC 11
    October. However, the Air Force Reserve Hurricane Hunter aircraft
    that investigated Odile near 1800 UTC that day found a much weaker
    system, with maximum 700 mb flight-level winds of 31 kt and maximum
    estimated surface winds of 46 kt from the Stepped Frequency
    Microwave Radiometer. In addition, intensity estimates from the
    Advanced Microwave Sounding Unit and the QuikScat scatterometer were
    between 40-50 kt on 10-11 October. The best track intensity blends
    theses estimates and shows 50 kt from 0600 UTC 10 October through
    1200 UTC 11 October, followed by rapid weakening.

    The aircraft reported a minimum pressure of 1010 mb at 1754 UTC 11
    October. However, a dropsonde released at the flight-level center
    reported 26-kt surface winds, suggesting that the actual central
    pressure was lower.

    Two ships reported winds of tropical storm-force in Odile. A ship
    with the call sign VRED4 reported 52-kt winds and a pressure of
    1002.0 mb at 1500 UTC 10 October. The **Westerdam** (call sign PINX)
    reported 35-kt winds at 0400 UTC 9 September. There were no reports
    of tropical storm-force winds from the coastal stations in Mexico.

c.  Casualty and Damage Statistics

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

d.  Forecast and Warning Critique

    The genesis of Odile was generally well-forecasted. The pre-Odile
    disturbance was first mentioned in the Tropical Weather Outlook on 4
    October, and the potential for tropical cyclone formation was first
    noted on 5 October. During the period of unfavorable wind shear on
    5-7 October, the outlooks noted that the upper-level winds were
    forecast to decrease and allow the system to become a tropical
    cyclone. However, experimental genesis forecasts were in the
    "medium" category (20-50% chance of tropical cyclone formation
    within 48 h) through this time, and did not reach the "high"
    category (greater than 50% chance of tropical cyclone formation
    within 48 h) until genesis occurred.

    A verification of official and guidance model track forecasts is
    given in Table 2. Average official track errors for Odile were 35,
    56, 69, 89, 151, and 237 n mi for the 12, 24, 36, 48, 72, and 96 h
    forecasts, respectively. The number of forecasts ranged from 15 at
    12 h to 1 at 96 h. These errors are lower than the average long-term
    official track errors (Table 2) through 48 h and larger at 72-96 h,
    although the number of forecasts at those latter times is small.
    None of the dynamical track forecast models had consistently lower
    errors than the official forecasts. However, the medium and deep
    versions of the Beta and Advection model (BAMM and BAMD) had
    significantly lower average errors than the official forecast at
    most times.

    Average official intensity errors were 8, 13, 17, 20, 30, and 35 kt
    for the 12, 24, 36, 48, 72, and 96 h forecasts, respectively (Table
    3). For comparison, the average long-term official intensity errors
    are 6, 10, 14, 16, 19, and 19 kt, respectively. The intensity
    forecasts had larger average errors than climatology and persistence
    (OCD5) at 12, 24, and 96 h, indicating the forecasts had no skill.
    The forecasts had a notable high bias, with several forecasts
    calling for Odile to become a hurricane. The GFDL model (GHMI) had
    lower average errors than the official forecast at all times, as did
    the consensus models ICON and IVCN.

The government of Mexico issued coastal watches and warnings for Odile
(Table 4). It should be noted that a hurricane watch was issued in
anticipation of Odile becoming a hurricane. The watch was discontinued
on 11 October when the aircraft data showed that Odile was weakening.

Table 1. Best track for Tropical Storm Odile, 8-12 October 2008.

+---------+---------+---------+---------+---------+-----------------+
| Da      | L       | Lo      | P       | Wind    | Stage           |
| te/Time | atitude | ngitude | ressure | Speed   |                 |
|         |         |         |         |         |                 |
| (UTC)   | \(N\)   | \(W\)   | (mb)    | (kt)    |                 |
+---------+---------+---------+---------+---------+-----------------+
| 08 /    | 11.7    | 89.4    | 1006    | 25      | tropical        |
| 1200    |         |         |         |         | depression      |
+---------+---------+---------+---------+---------+-----------------+
| 08 /    | 11.9    | 90.5    | 1006    | 30      | \"              |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 09 /    | 12.2    | 91.5    | 1006    | 30      | \"              |
| 0000    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 09 /    | 12.5    | 92.8    | 1005    | 35      | tropical storm  |
| 0600    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 09 /    | 12.7    | 93.9    | 1000    | 45      | \"              |
| 1200    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 09 /    | 13.1    | 94.7    | 1000    | 45      | \"              |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 10 /    | 13.5    | 95.4    | 1000    | 45      | \"              |
| 0000    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 10 /    | 13.8    | 96.2    | 997     | 50      | \"              |
| 0600    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 10 /    | 14.2    | 96.9    | 997     | 50      | \"              |
| 1200    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 10 /    | 15.0    | 97.9    | 997     | 50      | \"              |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 11 /    | 15.7    | 98.9    | 997     | 50      | \"              |
| 0000    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 11 /    | 16.3    | 100.1   | 997     | 50      | \"              |
| 0600    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 11 /    | 16.8    | 101.2   | 997     | 50      | \"              |
| 1200    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 11 /    | 17.4    | 102.3   | 1004    | 45      | \"              |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 12 /    | 17.8    | 103.5   | 1005    | 35      | \"              |
| 0000    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 12 /    | 18.1    | 104.1   | 1006    | 30      | tropical        |
| 0600    |         |         |         |         | depression      |
+---------+---------+---------+---------+---------+-----------------+
| 12 /    | 18.3    | 104.3   | 1006    | 25      | \"              |
| 1200    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 12 /    | 18.6    | 104.5   | 1007    | 25      | \"              |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 13 /    | 18.4    | 104.6   | 1007    | 25      | remnant low     |
| 0000    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 13 /    | 18.0    | 105.0   | 1008    | 20      | \"              |
| 0600    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 13 /    | 17.4    | 105.0   | 1008    | 20      | \"              |
| 1200    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 13 /    |         |         |         |         | dissipated      |
| 1800    |         |         |         |         |                 |
+---------+---------+---------+---------+---------+-----------------+
| 11 /    | 16.3    | 100.1   | 997     | 50      | minimum         |
| 0600    |         |         |         |         | pressure        |
+---------+---------+---------+---------+---------+-----------------+

Table 2. Track forecast evaluation (heterogeneous sample) for Tropical
Storm Odile, 8-12 October 2008. Forecast errors (n mi) are followed by
the number of forecasts in parentheses. Errors smaller than the NHC
official forecast are shown in boldface type.

+-----------+-------+-------+-------+-------+-------+-------+-------+
| Forecast  | For   |       |       |       |       |       |       |
| Technique | ecast |       |       |       |       |       |       |
|           | P     |       |       |       |       |       |       |
|           | eriod |       |       |       |       |       |       |
|           | (h)   |       |       |       |       |       |       |
+===========+=======+=======+=======+=======+=======+=======+=======+
|           | 12    | 24    | 36    | 48    | 72    | 96    | 120   |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| CLP5      | 45    | 75    | 96    | 123   | 208 ( | 414 ( |       |
|           | (16)  | (14)  | (12)  | (10)  | 6)    | 2)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFNI      | 64 (  | 157 ( | 259 ( | 318 ( |       |       |       |
|           | 9)    | 7)    | 6)    | 5)    |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFDI      | 39    | 62    | 95    | 109 ( | 278 ( | 324 ( |       |
|           | (16)  | (14)  | (12)  | 9)    | 6)    | 2)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| HWFI      | 60    | 97    | 123   | 138   | 210 ( | **    |       |
|           | (16)  | (14)  | (12)  | (10)  | 5)    | 182** |       |
|           |       |       |       |       |       | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NAMI      | 40 (  | *     | 105 ( |       |       |       |       |
|           | 6)    | *47** | 2)    |       |       |       |       |
|           |       | ( 2)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFSI      | 47    | 66    | 89    | 95 (  | **    | **    |       |
|           | (13)  | (11)  | (10)  | 9)    | 138** | 137** |       |
|           |       |       |       |       | ( 5)  | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| AEMI      | 61    | 102   | 152 ( | 170 ( | 270 ( | 412 ( |       |
|           | (11)  | (10)  | 9)    | 7)    | 5)    | 1)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NGPI      | 67    | 111   | 95 (  | 123 ( | 376 ( | 732 ( |       |
|           | (13)  | (10)  | 9)    | 7)    | 3)    | 2)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| UKMI      | 37    | 68    | 125 ( | 206 ( | 470 ( |       |       |
|           | (13)  | (11)  | 9)    | 5)    | 3)    |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| EGRI      | 45    | 88 (  | 205 ( | 321 ( |       |       |       |
|           | (13)  | 9)    | 7)    | 4)    |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| EMXI      | 48    | 83    | 105 ( | 93 (  | **    | **    |       |
|           | (11)  | (10)  | 8)    | 6)    | 112** | 121** |       |
|           |       |       |       |       | ( 3)  | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMD      | 43    | 61    | *     | *     | **    | **    |       |
|           | (16)  | (14)  | *67** | *71** | 124** | 150** |       |
|           |       |       | (12)  | (10)  | ( 6)  | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMM      | 42    | *     | *     | *     | *     | *     |       |
|           | (16)  | *55** | *53** | *44** | *69** | *66** |       |
|           |       | (14)  | (12)  | (10)  | ( 6)  | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMS      | 52    | 78    | 108   | 130   | 159 ( | **    |       |
|           | (15)  | (14)  | (12)  | (10)  | 6)    | 129** |       |
|           |       |       |       |       |       | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| LBAR      | 41    | 67    | 88    | 93    | 235 ( | 285 ( |       |
|           | (15)  | (14)  | (12)  | (10)  | 6)    | 2)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| TCON      | 37 (  | *     | 90 (  | 113 ( |       |       |       |
|           | 9)    | *54** | 4)    | 2)    |       |       |       |
|           |       | ( 5)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| TVCN      | 39    | 58    | 80    | 106   | 189 ( | 361 ( |       |
|           | (16)  | (14)  | (12)  | (10)  | 6)    | 2)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| TVCC      | 39    | *     | *     | *     | 163 ( | **    |       |
|           | (16)  | *55** | *68** | *82** | 6)    | 234** |       |
|           |       | (14)  | (12)  | (10)  |       | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GUNA      | 37 (  | 64 (  | 109 ( | 141 ( |       |       |       |
|           | 9)    | 5)    | 4)    | 2)    |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| FSSE      | 37    | *     | 82 (  | 105 ( | *     |       |       |
|           | (12)  | *54** | 8)    | 6)    | *39** |       |       |
|           |       | (10)  |       |       | ( 2)  |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| OFCL      | 35    | 56    | 69    | 89 (  | 151 ( | 237 ( |       |
|           | (15)  | (13)  | (11)  | 9)    | 5)    | 1)    |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NHC       | 31.9  | 55.1  | 77.4  | 97.9  | 136.2 | 180.1 | 226.1 |
| Official  | (     | (     | (979) | (849) | (620) | (439) | (293) |
|           | 1282) | 1129) |       |       |       |       |       |
| (         |       |       |       |       |       |       |       |
| 2003-2007 |       |       |       |       |       |       |       |
| mean)     |       |       |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+

Table 3. Intensity forecast evaluation (heterogeneous sample) for
Tropical Storm Odile, 8-12 October 2008. Forecast errors (kt) are
followed by the number of forecasts in parentheses. Errors smaller than
the NHC official forecast are shown in boldface type.

+-----------+-------+-------+-------+-------+-------+-------+-------+
| Forecast  | For   |       |       |       |       |       |       |
| Technique | ecast |       |       |       |       |       |       |
|           | P     |       |       |       |       |       |       |
|           | eriod |       |       |       |       |       |       |
|           | (h)   |       |       |       |       |       |       |
+===========+=======+=======+=======+=======+=======+=======+=======+
|           | 12    | 24    | 36    | 48    | 72    | 96    | 120   |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| OCD5      | **    | **1   | 20.2  | 30.0  | 32.7  | **    |       |
|           | 5.9** | 2.1** | (12)  | (10)  | ( 6)  | 5.0** |       |
|           | (16)  | (14)  |       |       |       | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GHMI      | **    | **1   | **1   | **1   | **    | **    |       |
|           | 6.3** | 0.6** | 3.2** | 3.3** | 8.3** | 5.5** |       |
|           | (16)  | (14)  | (12)  | ( 9)  | ( 6)  | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFNI      | **    | **    | **1   | **1   |       |       |       |
|           | 7.2** | 9.1** | 3.5** | 3.8** |       |       |       |
|           | ( 9)  | ( 7)  | ( 6)  | ( 5)  |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| HWFI      | 7.7   | 14.1  | **1   | **1   | **1   | **    |       |
|           | (16)  | (14)  | 7.0** | 6.2** | 3.0** | 1.0** |       |
|           |       |       | (12)  | ( 9)  | ( 5)  | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| LGEM      | **    | 14.5  | 18.0  | 20.9  | **2   | **2   |       |
|           | 7.2** | (14)  | (12)  | (10)  | 4.7** | 9.0** |       |
|           | (16)  |       |       |       | ( 6)  | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| DSHP      | 7.8   | 13.3  | 19.4  | 22.5  | **2   | 37.0  |       |
|           | (16)  | (14)  | (12)  | (10)  | 9.2** | ( 2)  |       |
|           |       |       |       |       | ( 6)  |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| FSSE      | **    | **1   | **1   | **1   | 43.0  |       |       |
|           | 5.4** | 0.5** | 4.8** | 9.7** | ( 2)  |       |       |
|           | (12)  | (10)  | ( 8)  | ( 6)  |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| ICON      | **    | **    | **    | **    | **1   | **1   |       |
|           | 5.4** | 8.7** | 9.3** | 9.3** | 5.2** | 8.0** |       |
|           | (16)  | (14)  | (12)  | ( 9)  | ( 5)  | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| IVCN      | **    | **    | **    | **    | **1   | **2   |       |
|           | 5.1** | 7.6** | 8.4** | 9.7** | 3.5** | 1.0** |       |
|           | (16)  | (14)  | (12)  | (10)  | ( 6)  | ( 2)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| OFCL      | 7.7   | 12.7  | 17.3  | 20.0  | 30.0  | 35.0  |       |
|           | (15)  | (13)  | (11)  | ( 9)  | ( 5)  | ( 1)  |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NHC       | 6.2   | 10.4  | 13.9  | 16.3  | 18.7  | 19.2  | 19.1  |
| Official  | (     | (     | (979) | (848) | (620) | (439) | (293) |
|           | 1282) | 1129) |       |       |       |       |       |
| (         |       |       |       |       |       |       |       |
| 2003-2007 |       |       |       |       |       |       |       |
| mean)     |       |       |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+

Table 4. Watch and warning summary for Tropical Storm Odile, 8-12
October 2008.

  ----------- ----------------------------- ------------------------------
  Date/Time   Action                        Location
  (UTC)                                     

  10 / 0300   Tropical Storm Watch issued   Punta Maldonado to Zihuatanejo

  10 / 1500   Tropical Storm Warning issued Lagunas de Chacahua to
                                            Zihuatanejo

  10 / 2100   Tropical Storm Watch issued   Zihuatanejo to Punta San Telmo

  11 / 0300   Tropical Storm Warning        Lagunas de Chacahua to Punta
              modified to                   San Telmo

  11 / 0300   Tropical Storm Watch issued   Punta San Telmo to Manzanillo

  11 / 0900   Tropical Storm Warning        East of Punta Maldonado
              discontinued                  

  11 / 0900   Hurricane Watch issued        Tecpan de Galeana to Punta San
                                            Telmo

  11 / 1500   Tropical Storm Watch          All
              discontinued                  

  11 / 1500   Tropical Storm Warning        Tecpan de Galeana to
              modified to                   Manzanillo

  11 / 1500   Hurricane Watch modified to   Zihuatanejo to Manzanillo

  11 / 2100   Tropical Storm Warning        Lazaro Cardenas to La Fortuna
              modified to                   

  11 / 2100   Hurricane Watch discontinued  All

  12 / 1500   Tropical Storm Warning        All
              discontinued                  
  ----------- ----------------------------- ------------------------------

![](media/image1.jpeg){width="8.194444444444445in"
height="6.229861111111111in"}

Figure 1. Best track positions for Tropical Storm Odile, 8-12 October
2008.

![](media/image2.wmf){width="8.628472222222221in"
height="5.7972222222222225in"}

Figure 2. Selected wind observations and best track maximum sustained
surface wind speed curve for Tropical Storm Odile, 8 -- 12 October 2008.
Aircraft observations have been adjusted for elevation using 90%, 80%,
and 80% reduction factors for observations from 700 mb, 850 mb, and 1500
ft, respectively. Dashed vertical lines correspond to 0000 UTC.

![](media/image3.wmf){width="8.611805555555556in"
height="5.7972222222222225in"}

Figure 3. Selected pressure observations and best track minimum central
pressure curve for Tropical Storm Odile, 8-12 October 2008. Dashed
vertical lines correspond to 0000 UTC.

[^1]: A digital record of the complete best track, including wind radii,
    can be found on line at <ftp://ftp.nhc.noaa.gov/atcf>. Data for the
    current year's storms are located in the *btk* directory, while
    previous years' data are located in the *archive* directory.