Danny track 2009
Because of the highly asymmetrical, subtropical nature of Danny
the low-level fixes of the Air Force and high-level fixes of the
NOAA flights have been separated and individual tracks made for
each set. The user is cautioned to use the track that most appropriately
applies to their implementation. A file with both fixes intermixed
is also provided for completeness.
Below are the wind center fixes and the tracks made from them
for Danny. The fixes were determined during post-processing using
methods developed by Dr. Hugh Willoughby and represent the center of
the subtropical cyclone's asymmetric wind field. Some fixes may be excluded,
usually due to closeness to or incompatibility with other fixes. On occasion,
interpolated points were included to make the track reasonable. The
reference altitude and source aircraft of the fix are also given, since
for weak or sheared systems the wind center may not be aligned vertically.
Following the fixes are the start and end times of inbound and outbound
legs of the aircraft, used to make horizontal profiles of the storm.
The centers are connected into a continuous tracks by using a series of
spline curves with varying degrees of curvature. The latitude and
longitude positions were output every two minutes to make the track
file.
Please note that this track is NOT the same as the NHC Best Track.
That can be found here.
This track is to be used with wind and sonde data for flights into
this storm, but caution should be used when using this track with
other data, such as radar. The wind field track is not the most
conservative measure of storm position, and may include many small
wobbles due to trochoidal motion of the wind center.
Reference
Willoughby, H.E., and M. B. Chelmow, 1982, "Objective determination of
hurricane tracks from aircraft observations", Mon. Wea. Rev.,
110, p.1298-1305.
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Last updated: June 30, 2010