Effects of Synoptic Surveillance on model forecasts for
Hurricane Ivan.

Quicktime movie of DLM wind analyses
Quicktime movie of DLM wind data initial increments

Assessments for each forecast time at
September 06, 2004 18 Z
September 07, 2004 00 Z 06 Z 12 Z 18 Z
September 08, 2004 00 Z 06 Z 12 Z 18 Z
September 09, 2004 00 Z 06 Z 12 Z 18 Z
September 10, 2004 00 Z 06 Z 12 Z 18 Z
September 11, 2004 00 Z 06 Z 12 Z 18 Z
September 12, 2004 00 Z 06 Z 12 Z 18 Z
September 13, 2004 00 Z 06 Z 12 Z 18 Z
September 14, 2004 00 Z 06 Z 12 Z 18 Z
September 15, 2004 00 Z 06 Z 12 Z 18 Z
September 16, 2004 00 Z 06 Z 12 Z

Fig 1a. Track forecast errors for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models for the Hurricane Ivan synoptic surveillance missions.

Fig 1b. Track forecast improvements for the GFS and GFDL models for the Hurricane Ivan synoptic surveillance missions.

(a)

(b)

Fig 2. Forecast errors for the landfall of Hurricane Ivan on Prickly Point, Granada, in the (a) cross- and (b) along-track directions for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models.

(a)

(b)

Fig 3. Forecast errors for the landfall of Hurricane Ivan on Portland Point, Jamaica, in the (a) cross- and (b) along-track directions for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models.

(a)

(b)

Fig 4. Forecast errors for the landfall of Hurricane Ivan on Grand Cayman, in the (a) cross- and (b) along-track directions for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models.

(a)

(b)

Fig 5. Forecast errors for the landfall of Hurricane Ivan on Cabo San Antonio, Cuba, in the (a) cross- and (b) along-track directions for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models.

(a)

(b)

Fig 6. Forecast errors for the landfall of Hurricane Ivan at Pine Beach, in the (a) cross- and (b) along-track directions for the no dropwindsonde (NO or NN) and the all dropwindsonde (AL) runs for the GFS and GFDL models.