Daniel was a 110-knot hurricane in the eastern Pacific Ocean basin and then
it threatened Hawaii while weakening. Daniel passed just north of Hawaii
and produced rough surf conditions there.
a. Synoptic history
Daniel's origin is associated with a tropical wave that moved from Africa to
the Atlantic on 8 July. This wave moved westward across the tropical
Atlantic, the Caribbean, and Central America without distinction. It was
not until 23 July that the wave's weather became well organized. It is
estimated from satellite imagery that a tropical depression formed on the
23rd, south of Mexico. The best track listing of center positions,
maximum one-minute wind speeds, and minimum central pressures begins at this
time and is given in Table 1.
Figure 1 is a plot of the best track.
Figure 2 and Figure 3
show plots of best-track wind speed and pressure curves as a
function of time, along with the data on which they are based. Best track
data west of 140° west longitude in the above table and figures were
provided by the Central Pacific Hurricane Center at Honolulu.
The track begins 575 n mi south-southeast of Manzanillo, Mexico on 23 July
and extends west-northwestward across the eastern and central Pacific basins
to just north of Hawaii by 1 August. Daniel was a hurricane from the
24th to the 29th and maximum winds reached 110 knots on
the 25th and 26th while still in the eastern Pacific
basin. Winds fluctuated from 90 knots on the 27th to 105 knots on
the 28 and then weakened to tropical storm levels on the 30th.
On the 31st, Daniel turned from west-northwest to northwestward
and its center passed parallel to and about 120 n mi north of the Hawaiian
island chain over the next two days. Its strongest winds did not affect
Hawaii. Daniel weakened to a tropical storm on the 30th, to a
depression on the 3rd, and finally dissipated on the
5th about 1000 n mi northwest of Hawaii.
A subtropical ridge anchored to the north was Daniel's controlling steering
feature until the track gradually turned from west-northwest to northwestward
on the 30th and 31st, into a weakness in the ridge near
Hawaii. Daniel's forward speed was generally from 15 to 20 knots, except
when it slowed to less than 10 knots while making the turn
toward the northwest.
b. Meteorological statistics
Center positions are taken from satellite images and intensity estimates are
based on the Dvorak satellite method, except for about 60 hours of Air Force
reconnaissance data from the 30th to the 1st. The
highest flight level wind speed during this period was 86 knots at 850
millibars. This value was an outlier as all other reconnaissance flight
level wind speeds were below 60 knots and is not shown in
Fig. 2. QuikSCAT
and SSM/I microwave satellite wind fields were used during Daniel's
formative stage to help determine the existence of, and to locate, the low
level circulation center.
c. Casualty and damage statistics
There were no reports of death or damage. There were reports of rough surf
conditions on the big island of Hawaii and on Maui's east-facing coast.
d. Forecast and warning critique
The official average track forecast errors for forecasts issued in the
eastern Pacific basin ranged from 50 nautical miles at 24 hours to 79
nautical at 48 hours to 190 nautical miles at 72 hours (21 cases). These
errors are 30 to 40 percent smaller than the 1990-99 mean official errors.
CLIPER errors for Daniel are also considerably smaller than their 1990-99
mean values. These small errors may be related to the small variation of
track heading. The track heading varied from only 275 to 295 degrees during
the five days of verification. The bias of the official intensity errors
was small...+3.6 knots at 72 hours, compared to the ten-year average of
Best track positions for Hurricane Daniel, 23 July - 5 August 2000.
Best track for Hurricane Daniel, 23 July - 05 August, 2000. Data west of
140° west longitude provided by the Central Pacific Hurricane Center at
|Lat. (°N)||Lon. (°W)
Best track one-min. wind speed curve for Hurricane Daniel, 23 July - 5
Best track minimum central pressure curve for Hurricane Daniel, 23 Jul - 5