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Showing posts from July, 2020

Verification of tracks made of Fay

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I made six tracks of Tropical Storm Fay, before it was assessed as a tropical cyclone. I made one more track after that point. Additionally, within 480 hours of cyclogenesis, there were six instances, when I missed cyclogenesis entirely. At longer lead times, position errors were excessive. As of this analysis, best track positions are available July 4, 18Z thru July 11, 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 six tracks (made before operationally recognized cyclogenesis), formation times ranged between July 5, 06Z and July 10, 12Z. Average was July 7, 14Z and median was July 7

Verification of tracks made of Edouard

I made no tracks of Tropical Storm Edouard, before or after it was assessed as a tropical cyclone. Instead, within 480 hours of cyclogenesis, there were 19 instances, when I missed cyclogenesis entirely. Let the crow enter my mouth! Due to lack of tracks, position comparisons aren't possible regardless of best track data period. 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". Statistics about formation or dissipation times aren't applicable. In the 19 cases (0 tracks, before the tracks and data agreed, that tropical storm would remain the peak intensity, and 19 complete misses), range, average and median of peak intensity was Category -2. At the lead time of

Verification of tracks made of Cristina

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I made 19 tracks of Tropical Storm Cristina, before it was assessed as a tropical cyclone. I made five more tracks after that point. Additionally, within 480 hours of cyclogenesis, there were four instances, when I missed cyclogenesis entirely. Detection rate was good, but originally the expected time of cyclogenesis (or the time of entering East Pacific) was weeks too early. Some of the early tracks began in North Atlantic; only the part in East Pacific will be counted as Cristina. As of this analysis, best track positions are available July 5, 18Z thru July 13, 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 "Cate

Verification of tracks made of TD 4-E

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I made 18 tracks of Tropical Depression Four-E, before it was assessed as a tropical cyclone. I made no tracks after that point. Additionally, within 480 hours of cyclogenesis, there were four instances, when I missed cyclogenesis entirely. Detection rate was good. Unsurprisingly for a weak, short-lived system, longevity and peak intensity were mostly overestimated. As of this analysis, best track positions are available June 27, 00Z thru June 30, 18Z, 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 18 tracks (made before operationally recognized cyclogenesis), formation times ranged between