Information about the wind field of a storm can be of crucial importance, particularly when said storm contains winds capable of producing significant damage. Meteorological and technological advances have led to more accurate methods for determining storm structure. Nowadays it is much easier to see what is going on in and around a threatening storm. The ability to see things in real-time has also been achieved through radar, satellite, and an improved surface observation system. Availability of meteorological information in real-time pertaining to severe storms opens up many new opportunities. As an example, engineers are developing damage functions, which utilize wind speeds measured in a severe storm to determine the degree of damage experienced in a particular area. If wind information about a hurricane making landfall were available in real-time, details concerning the amount of damage could also be determined in real-time, and emergency management officials could prepare in advance to send out teams to exact locations where the damage was greatest once the storm has passed. One problem exists with this scenario: how is the wind field of a hurricane, for example, going to be determined in real-time if surface observations happen to be sparse?
This study looks at a method known as Synthetic Dual-Doppler (SDD) analysis, which is applied to Hurricane Opal as it made landfall near Pensacola, Florida, on 4 October 1995. Data from the Doppler radar located at Eglin AFB, Florida (KEVX) was obtained for analysis. Two volume scans containing radial velocity data recorded at two different times were used to create one near-surface wind field representative of a time mid-way between the two volume scans used. The velocity data from the images were interpolated through Cressman analysis to a Cartesian grid. The interpolated data were then fed into equations emulating dual-Doppler geometry, which produced the two-dimensional wind field. This procedure was performed for a number of time periods near landfall. The results were satisfactory, with the SDD-produced wind fields showing the strongest winds to be in an area where surface stations did, indeed, record Opal's highest winds over land. Comparison of the SDD-produced wind fields to other wind fields for Opal revealed some similarities both in maximum intensity and location of these maxima.