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Showing posts from October, 2018

Verification of a track made on Kirk using GEFS mean fields

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I made one track about Tropical Storm Kirk. Additionally, within 384 hours of cyclogenesis, there were 16 instances, when I missed cyclogenesis entirely. As of this analysis, best track positions are available September 20, 00Z thru September 29, 00Z, and as such, position comparisons are possible only for this timespan. Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2". In the track, range, average and median of formation time was September 25, 06Z. In the 17 cases (1 track and 16 complete misses), peak intensity ranged between Category -2 and Category 2. Average was Category -1.76 and median was Category -2. In the track, range, average and median of dissipation ti

Verification of tracks made on TD 11 using GEFS mean fields

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I made five tracks about Tropical Depression Eleven. Additionally, within 384 hours of cyclogenesis, there were 15 instances, when I missed cyclogenesis entirely. Brevity was somewhat well predicted, but both formation and dissipation times were generally too early. TD 11 ended up becoming nameable storm in most of the tracks, often a hurricane. As of this analysis, best track positions are available September 18, 00Z thru September 23, 12Z, and as such, position comparisons are possible only for this timespan. Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2". In the five tracks, formation times ranged between September 16, 00Z and September 19, 12Z. Average was S

Verification of tracks made on Joyce using GEFS mean fields

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I made two tracks about Tropical Storm Joyce. Additionally, within 384 hours of cyclogenesis, there were 16 instances, when I missed cyclogenesis entirely. Even in those two cases, where I detected Joyce, I projected it to remain subtropical. As of this analysis, best track positions are available September 11, 12Z thru September 19, 00Z, and as such, position comparisons are possible only for this timespan.   Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2". In the 2 tracks, formation times ranged between September 12, 00Z and September 12, 06Z. Average was September 12, 03Z and median was September 12, 03Z. In the 18 cases (2 tracks and 16 complete misses), p

Verification of tracks made on Isaac using GEFS mean fields

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I made 33 tracks about Hurricane Isaac. Additionally, within 384 hours of cyclogenesis, there were two instances, when I missed cyclogenesis entirely. Peak intensity was generally assumed too high, and Isaac was also expected to be more long-lived. Cyclogenesis was projected to happen too far east and too early. Track forecast was excellent in long range. As of this analysis, best track positions are available September 2, 18Z thru September 17, 06Z, and as such, position comparisons are possible only for this timespan. Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2". In the 33 tracks, formation times ranged between September 3, 06Z and September 7, 12Z. Average was Sep

Verification of tracks made on Helene using GEFS mean fields

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I made 21 tracks about Hurricane Helene. Additionally, within 384 hours of cyclogenesis, there were four instances, when I missed cyclogenesis entirely. Timing and position of cyclogenesis was very well predicted weeks in advance. At shorter lead times, there was only a little improvement. Track forecast accuracy was variable, as was predicted peak intensity. Longevity of the cyclone also varied greatly. As of this analysis, best track positions are available September 6, 00Z thru September 16, 12Z, and as such, position comparisons are possible only for this timespan. Since I give only SSHS categories in my tracks, I don't calculate intensity errors in units of speed, but in categories. For this purpose, I define tropical or subtropical storms as "Category 0", tropical or subtropical depressions as "Category -1" and non-existence of a tropical or subtropical cyclone as "Category -2". In the 21 tracks, formation times ranged between Septe