Number range CHAPTERTropical Cyclone Report

Tropical Storm Tammy

5 - 6 October 2005

Stacy R. Stewart

National Hurricane Center

28 January 2006

Tammy was a short-lived tropical storm that developed from a complex
interaction between a vigorous tropical wave and an upper-level trough.
The cyclone made landfall along the northeastern Florida coast and
caused only minor damage.

a.  Synoptic History

    A tropical wave, accompanied by a broad surface low pressure system
    and curved convective cloud bands, crossed the coast of western
    Africa on 24 September. The wave moved west-northwestward and lost
    most of its convection until 2 October when the system was located
    just north of the Leeward Islands and began to interact with the
    eastern portion of a large negatively-tilted mid- to upper-level
    trough. Although the amount and vertical depth of the thunderstorm
    activity continued to increase through 3 October, moderate
    upper-level shear on the east side of the large trough inhibited any
    significant amplification of the wave. QuikSCAT satellite winds and
    reports from the Bahama Islands on both 3 and 4 October confirmed
    the presence of a sharp surface trough but showed no closed
    circulation. Late on 4 October, the northern portion of the tropical
    wave broke off and turned northwestward, and began to move closer to
    the upper-level trough axis where the vertical shear was weakest.
    The northwestward motion brought the surface trough into close
    proximity with an extensive area of surface high pressure situated
    over the central Atlantic Ocean. This caused an increase in the
    pressure gradient between the two systems, resulting in a broad area
    of gale-force winds just east of the Bahamas.

    As the surface trough moved over the Bahamas early on 5 October, a
    small mass of deep convection with cloud top temperatures lower than
    -80^o^ C developed along the trough axis. By 0400 UTC, surface
    observations from Florida and the Bahamas indicated a small surface
    low pressure system was forming over the Straits of Florida. Doppler
    radar data from the NOAA National Weather Service Forecast Offices
    in Miami and Melbourne, Florida also indicated a low to mid-level
    cyclonic circulation had formed within the convective cloud mass. By
    0600 UTC, surface observations indicated a low pressure center had
    developed just off the southeastern Florida coast about 20 n mi east
    of Jupiter. Since 35-kt winds were already present east of the newly
    formed surface low, the cyclone skipped the tropical depression
    phase. 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. Best track positions and intensities are
    listed in Table 1.

    Under the influence of southeasterly steering flow on the east side
    of a deep-layer low pressure system that was over the eastern Gulf
    of Mexico, Tammy moved steadily northwestward at about 10 kt,
    paralleling the Florida east coast. By late on 5 October, Tammy
    turned toward the west-northwest as the cyclone moved into the
    northeastern quadrant of the mid- to upper level low. The strong
    upper-level difluence in this area aided in the development of
    persistent deep convection, which allowed Tammy to strengthen before
    it made landfall along the northeastern Florida coast near Atlantic
    Beach at around 2300 UTC.

    After making landfall, Tammy's forward speed increased to 14-19 kt
    as the cyclone turned westward across southern Georgia early on 6
    October. Land effects caused the cyclone to quickly weaken to a
    depression by 1200 UTC and degenerate into a remnant low pressure
    system just 6 h later. The weak surface low drifted slowly
    southwestward across extreme southeastern Alabama and into the
    western Florida panhandle for the next 12h. By 0600 UTC 7 October,
    the remnant low was absorbed by a larger deep-layer extratropical
    low pressure system over the east-central Gulf of Mexico.

b.  Meteorological Statistics

    Observations in Tammy (Figs. 2 and 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), as well as flight-level
    observations from flights of the 53^rd^ Weather Reconnaissance
    Squadron of the U. S. Air Force Reserve Command. Microwave satellite
    imagery from NOAA polar-orbiting satellites, the NASA Tropical
    Rainfall Measuring Mission (TRMM), the NASA QuikSCAT, and Defense
    Meteorological Satellite Program (DMSP) satellites were also useful
    in tracking Tammy. Data from NOAA National Weather Service (NWS)
    Doppler radars (Figure 4) was crucial in tracking Tammy's center and
    monitoring the evolution of the storm system in the early morning
    hours of 5 October until the first reconnaissance flight arrived at
    around 1600 UTC later that day.

    Ship reports of winds of tropical storm force associated with Tammy
    are given in Table 2, and selected surface observations from land
    stations and data buoys are given in Table 3.

    There were only limited aircraft reconnaissance data as a result of
    the short-fused nature of Tammy's development and its short
    lifetime. The maximum flight-level wind observed at 1500 ft was 51
    kt at 1816 UTC 5 October. Using an 80% adjustment factor yields a
    surface wind estimate of about 40 kt. Two ships (call signs A8GQ8
    and WDC692) located northeast of Tammy's center reported sustained
    winds of 45 and 44 kt at 0200 UTC and 0300 UTC 6 October,
    respectively, and those reports were basis for assigning a peak
    intensity of 45 kt. The extrapolated minimum central pressure
    reported by the reconnaissance aircraft was 1001 mb at 2005 UTC 5
    October. The lowest pressure noted in surface observations was
    1002.0 mb at the Mayport, Florida Naval Base as the center of Tammy
    passed just a few miles south of that location. Doppler velocity
    data from the Jacksonville WSR-88D also supported approximately
    45-kt surface winds.

c.  Casualty and Damage Statistics

The primary effect from Tammy were floods caused by heavy rainfall and
storm surge. Rainfall totals were generally in the 3-5 in range.
However, some isolated rainfall amounts near 10 in occurred over
portions of extreme southeastern Georgia, which resulted in significant
flooding in McIntosh County. Fifteen to twenty roads were washed out,
two pond dams burst, and five homes were damaged in the county. In Glynn
County, Georgia, heavy rainfall caused flood damage to several homes.

In addition to the rain-induced freshwater flooding, a storm surge
generally in the 2-4 ft range caused saltwater floods along the coasts
and barrier islands of extreme northeastern Florida, Georgia and South
Carolina. More than 2 ft of beach erosion occurred in St. Johns and
Flagler County, Florida. In Nassau County, Florida, several boardwalks
were damaged or washed away. Farther north, significant beach erosion
occurred at Tybee Island, Georgia and at Edisto Beach and Isle of Palms,
South Carolina. Several feet of beach were lost and several homes were
damaged on Edisto Beach.

An F0 tornado damaged a hotel roof and snapped trees and power poles
near Glynco Airport (KBQK), Brunswick, Georgia during the late afternoon
of 5 October.

Information from the American Insurance Services Group indicate that
insured property damage caused by Tropical Storm Tammy was less than the
catastrophe threshold of \$25 million.

d.  Forecast and Warning Critique

    Forecast verification statistics are limited since Tammy only lasted
    for 36 h. Average official track errors (with the number of cases in
    parentheses) for Tammy were 41 (5), 85 (3), and 120 (1) n mi for the
    12, 24, and 36 h forecasts, respectively. These errors are slightly
    lower than the average official track errors for the 10-yr period
    1995-2004 (42, 75, and 107 n mi, respectively). The official NHC
    forecast (OFCL) outperformed all of the available model guidance at
    12 h. At 24 h, the interpolated GFDL, GFS, and NOGAPS models
    performed superbly and produced track errors about half those of the
    OFCL forecasts.

    Average official intensity errors were 4, 7, and 8 kt for the 12,
    24, and 36 h forecasts, respectively. These errors were much lower
    than the average official intensity errors over the 10-yr period
    1995-2004 are 6, 10, and 12 kt, respectively.

    A summary of tropical cyclone coastal watches and warnings for
    Tropical Storm Tammy are listed in Table 5. Since Tammy did not
    become a tropical cyclone until it was very close to land, there was
    only about 6 h of lead time before the onset of tropical storm-force
    winds occurred in the tropical storm warning area.

    Tammy's potential tropical cyclone development was reasonably well
    anticipated given the uncertainty in how the system would interact
    with and be affected by the upper-level trough over the eastern Gulf
    Mexico and Florida. Possible genesis was first mentioned on the 0230
    UTC 4 October Tropical Weather Outlook and associated graphics
    issued by the Tropical Prediction Center's National Hurricane Center
    and Tropical Analysis and Forecast Branch. This resulted in a little
    more than 24-hour genesis lead time.

    e\. Acknowledgements

    Much of the data for this report was supplied by the National
    Weather Service WFOs in Melbourne and Jacksonville, Florida, and
    Charleston, South Carolina. NOAA buoy and C-MAN data were provided
    by the National Data Buoy Center.

Number range CHAPTERTable 1. Best track for Tropical Storm Tammy, 5-6
October 2005.

+---------+--------+--------+--------+-----------+--------------------+
| Da      | La     | Lon    | Pr     | Wind      | Stage              |
| te/Time | titude | gitude | essure | Speed     |                    |
|         |        |        |        |           |                    |
| (UTC)   | (N     | (W     | (mb)   | (kt)      |                    |
|         | ^o^)   | ^o^)   |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 05 /    | 27.3   | 79.7   | 1006   | 35        | tropical storm     |
| 0600    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 05 /    | 28.3   | 80.2   | 1004   | 40        | \"                 |
| 1200    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 05 /    | 29.5   | 80.9   | 1001   | 45        | \"                 |
| 1800    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 06 /    | 30.5   | 81.6   | 1002   | 45        | \"                 |
| 0000    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 06 /    | 31.3   | 82.8   | 1005   | 35        | \"                 |
| 0600    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 06 /    | 31.8   | 84.6   | 1005   | 25        | tropical           |
| 1200    |        |        |        |           | depression         |
+---------+--------+--------+--------+-----------+--------------------+
| 06 /    | 31.2   | 85.8   | 1006   | 15        | \"                 |
| 1800    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 07 /    | 30.3   | 85.6   | 1005   | 10        | remnant low        |
| 0000    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+
| 07 /    |        |        |        |           | absorbed by larger |
| 0600    |        |        |        |           | extratropical low  |
+---------+--------+--------+--------+-----------+--------------------+
| 05 /    | 30.4   | 81.4   | 1002   | 45        | landfall near      |
| 2300    |        |        |        |           | Atlantic Beach,    |
|         |        |        |        |           | Florida            |
+---------+--------+--------+--------+-----------+--------------------+
| 05 /    | 29.5   | 80.9   | 1001   | 45        | minimum pressure   |
| 1800    |        |        |        |           |                    |
+---------+--------+--------+--------+-----------+--------------------+

Number range CHAPTERTable 2. Selected ship and buoy reports with winds
of at least 34 kt for Tropical Storm Tammy, 5-6 October 2005.

+----------+--------------+---------+-----------+-----------+--------+
| D        | Ship call    | L       | Longitude | Wind      | Pr     |
| ate/Time | sign         | atitude |           |           | essure |
| (UTC)    |              |         | (W)      | dir/speed |        |
|          |              | (N)    |           | (kt)      | (mb)   |
+----------+--------------+---------+-----------+-----------+--------+
| 05 /     | Buoy 41012   | 30.0    | 80.6      | 080 / 29  | 1003.7 |
| 1000     |              |         |           | G 38      |        |
+----------+--------------+---------+-----------+-----------+--------+
| 05 /     | WFJN         | 31.1    | 79.0      | 130 / 39  | 1013.0 |
| 2300     |              |         |           |           |        |
+----------+--------------+---------+-----------+-----------+--------+
| 06 /     | Buoy 41004   | 32.5    | 79.1      | 120 / 38  | 1010.7 |
| 0120     |              |         |           | G 48      |        |
+----------+--------------+---------+-----------+-----------+--------+
| 06 /     | Buoy 41008   | 31.4    | 80.9      | 120 / 35  | 1005.8 |
| 0130     |              |         |           | G 46      |        |
+----------+--------------+---------+-----------+-----------+--------+
| 06 /     | A8GQ8        | 32.4    | 78.3      | 110 / 45  | 1016.0 |
| 0200     |              |         |           |           |        |
+----------+--------------+---------+-----------+-----------+--------+
| 06 /     | WDC692       | 31.4    | 80.7      | 120 / 44  | 1003.5 |
| 0300     |              |         |           |           |        |
+----------+--------------+---------+-----------+-----------+--------+
| 06 /     | PDAS         | 31.7    | 80.3      | 110 / 35  | 1008.8 |
| 0600     |              |         |           |           |        |
+----------+--------------+---------+-----------+-----------+--------+

G peak gust

Number range CHAPTERTable 3. Selected surface observations Tropical
Storm Tammy, 5-6 October 2005

+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Location        | M   |     | Ma    |       |   | St  | St  | To  |
|                 | ini |     | ximum |       |   | orm | orm | tal |
|                 | mum |     | Su    |       |   | su  |     |     |
|                 | Sea |     | rface |       |   | rge | t   | r   |
|                 | Le  |     |       |       |   |     | ide | ain |
|                 | vel |     | Wind  |       |   | (   |     |     |
|                 | Pr  |     | Speed |       |   | ft) | (   | (   |
|                 | ess |     |       |       |   | ^c^ | ft) | in) |
|                 | ure |     |       |       |   |     | ^d^ |     |
+=================+=====+=====+=======+=======+===+=====+=====+=====+
|                 | Da  | Pre | Date/ | Sust  | G |     |     |     |
|                 | te/ | ss. |       | ained | u |     |     |     |
|                 |     |     | time  |       | s |     |     |     |
|                 | t   | (   |       | (k    | t |     |     |     |
|                 | ime | mb) | (UT   | t)^b^ |   |     |     |     |
|                 |     |     | C)^a^ |       | ( |     |     |     |
|                 | (U  |     |       |       | k |     |     |     |
|                 | TC) |     |       |       | t |     |     |     |
|                 |     |     |       |       | ) |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| **Florida**     |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Cecil Field     | 0   | 100 |       |       |   |     |     |     |
| Airport (KVQQ)  | 5/2 | 4.7 |       |       |   |     |     |     |
|                 | 325 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Craig Airport   | 0   | 100 |       |       |   |     |     |     |
| (KCRG)          | 5/2 | 2.4 |       |       |   |     |     |     |
|                 | 341 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Fernandina      |     |     |       |       |   | 3.2 |     |     |
| Beach           |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Fernandina      |     |     |       |       |   |     |     | 4   |
| Beach (FRBF1)   |     |     |       |       |   |     |     | .40 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Gainesville     | 0   | 100 |       |       |   |     |     |     |
| Airport (KGNV)  | 5/2 | 5.1 |       |       |   |     |     |     |
|                 | 053 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Hastings ARC    |     |     |       |       |   |     |     | 3   |
| (HTGF1)         |     |     |       |       |   |     |     | .63 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Jacksonville    | 0   | 100 | 05    |       | 3 |     |     | 3   |
| Int'l Airport   | 5/2 | 3.0 | /1020 |       | 3 |     |     | .41 |
| (KJAX)          | 340 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Jacksonville    | 0   | 100 |       |       |   |     |     |     |
| Naval Air       | 5/2 | 2.7 |       |       |   |     |     |     |
| Station (KNIP)  | 242 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Mayport Bar     |     |     |       |       |   | 2.3 |     |     |
| Pilots Station  |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Mayport Naval   | 0   | 100 | 0     |       | 3 |     |     |     |
| Base (KNRB)     | 5/2 | 2.0 | 51611 |       | 6 |     |     |     |
|                 | 253 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| St. Augustine   | 0   | 100 | 05    |       | 3 |     |     |     |
| C-MAN           | 5/2 | 2.9 | /0851 |       | 7 |     |     |     |
|                 | 000 |     |       |       |   |     |     |     |
| (SAUF1) 16.5 m  |     |     |       |       |   |     |     |     |
| elev.           |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| St. Augustine   | 0   | 100 | 05    |       | 3 |     |     |     |
| Airport (KSGJ)  | 5/2 | 2.4 | /1055 |       | 4 |     |     |     |
|                 | 055 |     |       |       |   |     |     |     |
|                 | ^e^ |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| St. Johns River |     |     |       |       |   | 2.5 |     |     |
| I-295 Bridge    |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Vilano Beach    |     |     |       |       |   | 3.0 |     |     |
| ICWW            |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
|                 |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| **Georgia**     |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Alma Airport    | 0   | 100 |       |       |   |     |     |     |
| (KAMG)          | 5/0 | 4.7 |       |       |   |     |     |     |
|                 | 547 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Brunswick       |     |     |       |       |   |     |     | 8   |
| (BRUG1)         |     |     |       |       |   |     |     | .30 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| B               | 0   | 100 | 06    |       | 3 |     |     | 9   |
| runswick/Glynco | 6/0 | 5.8 | /0100 |       | 8 |     |     | .93 |
| Airport         | 020 |     |       |       |   |     |     |     |
|                 |     |     |       |       |   |     |     |     |
| (KBQK)          |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Bru             | 0   | 100 | 06    |       | 4 |     |     |     |
| nswick/McKinnon | 6/0 | 4.1 | /0053 |       | 0 |     |     |     |
| Airport (KSSI)  | 050 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Fort Pulaski    |     |     | 06    | 38    | 4 | 4.2 |     |     |
| (NOS station)   |     |     | /0200 |       | 5 |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Nahunta 3E      |     |     |       |       |   |     |     | 9   |
| (NAHG1)         |     |     |       |       |   |     |     | .11 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Patterson       |     |     |       |       |   |     |     | 3   |
| (PATG1)         |     |     |       |       |   |     |     | .96 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Savannah        |     |     |       |       |   |     |     | 6   |
| (unofficial)    |     |     |       |       |   |     |     | .49 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Savannah        | 0   | 100 |       |       |   |     |     | 4   |
| Airport (KSAV)  | 6/1 | 7.5 |       |       |   |     |     | .44 |
|                 | 609 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| SKMG1 U.S. Navy | 0   | 100 | 06    | 45    | 5 |     |     |     |
| Tower           | 5/2 | 8.0 | /0234 |       | 2 |     |     |     |
|                 | 300 |     |       |       |   |     |     |     |
| 31.5N 80.2W /   |     |     |       |       |   |     |     |     |
| 50 m elev.      |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| SPAG1 U.S. Navy |     |     | 06    | 43    | 4 |     |     |     |
| Tower           |     |     | /0231 |       | 7 |     |     |     |
|                 |     |     | ^e^   |       |   |     |     |     |
| 31.4N 80.6W /   |     |     |       |       |   |     |     |     |
| 50 m elev.      |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| TYBG1 U.S. Navy | 0   | 100 | 06    | 41    | 5 |     |     |     |
| Tower           | 6/0 | 7.9 | /0229 |       | 2 |     |     |     |
|                 | 129 |     | ^e^   |       |   |     |     |     |
| 31.6N 79.9W /   |     |     |       |       |   |     |     |     |
| 34 m elev.      |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Waycross 4NE    |     |     |       |       |   |     |     | 3   |
| (AYSG1)         |     |     |       |       |   |     |     | .42 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Woodbine        |     |     |       |       |   |     |     | 9   |
| (WBNG1)         |     |     |       |       |   |     |     | .21 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
|                 |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| **South         |     |     |       |       |   |     |     |     |
| Carolina**      |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Charleston      | 0   | 100 | 05    | 28    | 3 |     |     | 3   |
| Airport (KCHS)  | 6/1 | 8.8 | /1619 |       | 5 |     |     | .63 |
|                 | 557 |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Downtown        |     |     | 05    |       | 4 |     |     | 3   |
| Charleston      |     |     | /1948 |       | 3 |     |     | .58 |
| (unofficial)    |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Charleston      |     |     |       |       |   | 2.6 |     |     |
| Harbor          |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Folly Beach     |     |     | 05    | 35    | 4 |     |     |     |
| C-MAN           |     |     | /2030 |       | 8 |     |     |     |
|                 |     |     |       |       |   |     |     |     |
| (FBIS) 5 m      |     |     |       |       |   |     |     |     |
| elev.           |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Fripp Island    |     |     |       |       |   | 3.3 |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Hilton Head     |     |     |       |       |   |     |     | 5   |
| (unofficial)    |     |     |       |       |   |     |     | .65 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Hinesville      |     |     |       |       |   |     |     | 5   |
| (unofficial)    |     |     |       |       |   |     |     | .16 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Ladson          |     |     |       |       |   |     |     | 3   |
| (unofficial)    |     |     |       |       |   |     |     | .54 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| Metter          |     |     |       |       |   |     |     | 4   |
| (unofficial)    |     |     |       |       |   |     |     | .69 |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+
| South Capers    |     |     |       |       |   | 2.5 |     |     |
| Island          |     |     |       |       |   |     |     |     |
+-----------------+-----+-----+-------+-------+---+-----+-----+-----+

^a^ Date/time is for sustained wind when both sustained and gust are
listed.

^b^ Except as noted, sustained wind averaging periods for C-MAN and
land-based ASOS reports are 2 min; buoy averaging periods are 8 min.

^c^ Storm surge is water height above normal astronomical tide level.

^d^ Storm tide is water height above National Geodetic Vertical Datum
(1929 mean sea level).

^e^ Last of several occurrences

Table 4. Preliminary forecast evaluation (heterogeneous sample) for
Tropical Storm

Tammy, 5-6 October 2005. Forecast errors (n mi) are followed by the
number of forecasts in

parentheses. Errors smaller than the NHC official forecast are shown in
bold-face type.

Verification includes the depression stage.

+-----------+-------+-------+-------+-------+-------+-------+-------+
| Number    | For   |       |       |       |       |       |       |
| range     | ecast |       |       |       |       |       |       |
| CHAPTE    | P     |       |       |       |       |       |       |
| RForecast | eriod |       |       |       |       |       |       |
| Technique | (h)   |       |       |       |       |       |       |
+===========+=======+=======+=======+=======+=======+=======+=======+
|           | 12    | 24    | 36    | 48    | 72    | 96    | 120   |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| CLP5      | 73 (  | 210 ( | 374 ( |       |       |       |       |
|           | 5)    | 3)    | 1)    |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFNI      | 58 (  | *     |       |       |       |       |       |
|           | 3)    | *51** |       |       |       |       |       |
|           |       | ( 1)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFDI      | 41 (  | *     | *     |       |       |       |       |
|           | 5)    | *59** | *74** |       |       |       |       |
|           |       | ( 3)  | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFDL \*   | 42 (  | *     |       |       |       |       |       |
|           | 4)    | *41** |       |       |       |       |       |
|           |       | ( 2)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFDN      | 75 (  | *     |       |       |       |       |       |
|           | 3)    | *77** |       |       |       |       |       |
|           |       | ( 2)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFSI      | 41 (  | *     | **    |       |       |       |       |
|           | 5)    | *70** | 101** |       |       |       |       |
|           |       | ( 3)  | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GFSO \*   | 50 (  | *     |       |       |       |       |       |
|           | 4)    | *45** |       |       |       |       |       |
|           |       | ( 2)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| AEMI      | 48 (  | *     | *     |       |       |       |       |
|           | 5)    | *64** | *93** |       |       |       |       |
|           |       | ( 3)  | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NGPI      | 51 (  | *     |       |       |       |       |       |
|           | 4)    | *44** |       |       |       |       |       |
|           |       | ( 1)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NGPS \*   | 78 (  | 114 ( |       |       |       |       |       |
|           | 4)    | 2)    |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| UKMI      | 131 ( | 261 ( |       |       |       |       |       |
|           | 3)    | 1)    |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| UKM \*    | 92 (  | 158 ( |       |       |       |       |       |
|           | 2)    | 1)    |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| A98E      | 52 (  | 140 ( | 223 ( |       |       |       |       |
|           | 5)    | 3)    | 1)    |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| A9UK      | 46 (  | 129 ( |       |       |       |       |       |
|           | 2)    | 1)    |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMD      | 57 (  | 99 (  | 144 ( |       |       |       |       |
|           | 5)    | 3)    | 1)    |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMM      | 48 (  | 89 (  | **    |       |       |       |       |
|           | 5)    | 3)    | 114** |       |       |       |       |
|           |       |       | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| BAMS      | 54 (  | *     | *     |       |       |       |       |
|           | 5)    | *76** | *66** |       |       |       |       |
|           |       | ( 3)  | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| CONU      | 45 (  | *     | *     |       |       |       |       |
|           | 5)    | *63** | *87** |       |       |       |       |
|           |       | ( 3)  | ( 1)  |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| GUNA      | 52 (  | *     |       |       |       |       |       |
|           | 3)    | *76** |       |       |       |       |       |
|           |       | ( 1)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| FSSE      | **8** | *     |       |       |       |       |       |
|           | ( 1)  | *70** |       |       |       |       |       |
|           |       | ( 1)  |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| OFCL      | 41 (  | 85 (  | 120 ( |       |       |       |       |
|           | 5)    | 3)    | 1)    |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+
| NHC       | 42    | 75    | 107   | 138   | 202   | 236   | 310   |
| Official  |       |       |       |       |       |       |       |
|           | \(3   | \(3   | \(2   | \(2   | \(2   | \(    | \(    |
| (         | 400\) | 116\) | 848\) | 575\) | 117\) | 649\) | 535\) |
| 1995-2004 |       |       |       |       |       |       |       |
| mean)     |       |       |       |       |       |       |       |
+-----------+-------+-------+-------+-------+-------+-------+-------+

\*Output from these models was unavailable at forecast time.

Errors given for the 96 and 120 h periods are averages over the
four-year period 2001-4

Number range CHAPTERTable 5. Watch and warning summary for Tropical
Storm Tammy, 5-6 October 2005.

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

  5 / 1100             Tropical Storm Warning issued            Cocoa Beach to South Santee
                                                                River

  5 / 1800             Tropical Storm Warning                   Flagler Beach to South Santee
                       modified to                              River

  6 / 0000             Tropical Storm Warning                   Fernandina Beach to South
                       modified to                              Santee River

  6 / 0900             Tropical Storm Warning                   Altamaha Sound to South Santee
                       modified to                              River

  6 / 1500             Tropical Storm Warning                   All
                       discontinued                             
  ----------- -------- ----------------------------- ---------- ------------------------------

![](media/image1.wmf){width="6.498611111111111in"
height="5.000694444444444in"}Number range CHAPTER

Number range CHAPTERFigure 1. Best track positions for Tropical Storm
Tammy, 5-6 October 2005.

![](media/image2.wmf){width="6.500694444444444in"
height="4.404861111111111in"}

Number range CHAPTERFigure 2. Selected wind observations and best track
maximum sustained surface wind speed

curve for Tropical Storm Tammy, 5-6 October 2005. Aircraft observations
have been adjusted

for elevation using an 80% reduction factor for observations from 1500
ft. Landfall occurred just

south of Mayport, Florida near Atlantic Beach around 2300 UTC 5 October
2005.

![](media/image3.wmf){width="6.49375in" height="4.409722222222222in"}

Number range CHAPTERFigure 3. Selected pressure observations and best
track minimum central pressure curve for

Tropical Storm Tammy, 5-6 October 2005.

![](media/image4.jpeg){width="6.499305555555556in"
height="6.004861111111111in"}

Number range CHAPTERFigure 4. Reflectivity image at 1834 UTC 5 October
from the NWS Jacksonville, FL WSR-88D Doppler weather radar. A small
mass of deep convection (50-55 dBZ) was co-located with the surface
center just east of the northeastern Florida coast near R8. Tammy was
its peak intensity of 45 kt at this time based on Doppler radar velocity
data. The small arrows and alphanumerics are the result of the radar
system's cell identification and tracking algorithm.