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Showing posts from August, 2019

Verification of non-detection of Gil

I made no tracks of Tropical Storm Gil. Within 384 hours of cyclogenesis, there were 14 instances, where I missed cyclogenesis. At the lead time of 1 day ( 24 hours), there were no misses. At the lead time of 2 days ( 48 hours), there were no misses. At the lead time of 3 days ( 72 hours), there was 1 miss. At the lead time of 4 days ( 96 hours), there were 2  misses. At the lead time of 5 days ( 120 hours), there were 2 misses. At the lead time of 6 days ( 144 hours), there were 2 misses. At the lead time of 7 days ( 168 hours), there were 2 misses. At the lead time of 8 days ( 192 hours), there were no misses. At the lead time of 9 days ( 216 hours), there were no misses. At the lead time of 10 days ( 240 hours), there was 1 miss. At the lead time of 11 days ( 264 hours), there was 1 miss. At the lead time of 12 days ( 288 hours), there was 1 miss. At the lead time of 13 days ( 312 hours), there was 1 miss. At the lead time of 14

Verification of tracks made of Flossie using GEFS mean fields

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I made seven tracks of Hurricane Flossie. Additionally, within 384 hours of cyclogenesis, there were two instances, when I missed cyclogenesis entirely. Timing of cyclogenesis was great, and location errors were pretty small. Intensity and longevity were mostly overestimated. As of this analysis, best track positions are available July 25, 12Z thru August 6, 00Z, and as such, position comparisons are possible only for this timespan. Getting out of the frame of East Pacific tracking map is considered equal to dissipation for the purpose of this verification. 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 seven tracks, formation times ranged between July 27, 06Z

Verification of tracks made of Erick using GEFS mean fields

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I made two tracks of Hurricane Erick. Additionally, within 384 hours of cyclogenesis, there were seven instances, when I missed cyclogenesis entirely. As of this analysis, best track positions are available July 25, 18Z thru August 6, 18Z, and as such, position comparisons are possible only for this timespan. Getting out of the frame of East Pacific tracking map is considered equal to dissipation for the purpose of this verification. 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 two tracks, formation times ranged between July 27, 00Z and July 28, 18Z. Average and median were July 27, 21Z. In the nine cases (2 tracks and 7 complete misses), peak inte

Verification of tracks made of Dalila using GEFS mean fields

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I made nine tracks of Tropical Storm Dalila. Additionally, within 384 hours of cyclogenesis, there were five instances, when I missed cyclogenesis entirely. Most of the tracks were made at least 16 days before actual cyclogenesis ; in those tracks, projected cyclogenesis was way too east, way too early. As of this analysis, best track positions are available July 14, 12Z thru July 25, 12Z, and as such, position comparisons are possible only for this timespan. Getting out of the frame of East Pacific tracking map is considered equal to dissipation for the purpose of this verification. 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 nine tracks, formation times r

Verification of tracks made on TD 4 (2017) using GEFS mean fields

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This is a repost from summer 2017 I made 17 tracks about Tropical Depression Four. In four additional cases, I tried to generate tracks, but I missed the system entirely. Mostly I predicted the system to become a major hurricane, so intensity was very biased. The error was finalized by the fact, that in many cases, I predicted the system to undergo cyclogenesis only at a time, when in fact the system had already degenerated. But position tracking performance was good, I think. Unfortunately the last best track entry was at 06Z on July 12, so it is not possible to verify track performance for the timeframe, when the remnant spin continued to Florida Straits. In one case, my track continued all the way to July 23, and most of them continued until July 19. 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 storms as "Category 0", tropical depressions a

Verification of tracks made on Franklin (2017) using GEFS mean fields

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I made 22 tracks about Hurricane Franklin. In five additional cases, while trying to generate tracks, I missed the system entirely. Intensity forecast was much better than in the case of TD 4 . Position forecast was also good to very large lead times. My analysis begins at August 1, 12Z, which is the earliest time, at which one of my tracks had cyclogenesis. Analysis ends at August 10, 12Z, since any continuation of Franklin's remnants into the Pacific and the possibility of regeneration there was not meant to be considered. 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 storms as "Category 0", tropical depressions as "Category -1" and non-existence of a tropical cyclone as "Category -2". I compare intensities only in cases, when either the best track data or my track has a tropical cyclone, or both. In other words, I leave