Verification of tracks made of Isaias

I made eleven tracks of Hurricane Isaias, before it was assessed as a tropical cyclone. I made three more tracks after that point. Additionally, within 480 hours of cyclogenesis, there were seven instances, when I missed cyclogenesis entirely. At times, position errors were excessive.

As of this analysis, best track positions are available July 23, 18Z thru August 5, 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 eleven tracks (made before operationally recognized cyclogenesis), formation times ranged between July 22, 06Z and August 2, 00Z. Average was July 28, 16Z and median was July 29, 12Z.

In the 19 cases (12 tracks, before the tracks and data agreed, that Category 1 would remain the peak intensity, and 7 complete misses), peak intensity ranged between Category -2 and  Category 5. Average was Category 0.26 and median was Category 0.

In the 14 tracks (made before operationally recognized degeneration into remnant low), dissipation times ranged between July 31, 00Z and August 11, 12Z. Average was August 4, 06Z and median was August 4, 03Z.

At the lead time of 1 day (24 hours), there were 4 hits, 1 false detection and 0 misses. 5 available position comparisons produce an average error of 79 nautical miles.

At the lead time of 2 days (48 hours), there were 5 hits, 2 false detections and 0 misses. 7 available position comparisons produce an average error of 184 nautical miles.

At the lead time of 3 days (72 hours), there were 5 hits, 1 false detection and 0 misses. 6 available position comparisons produce an average error of 193 nautical miles.

At the lead time of 4 days (96 hours), there were 5 hits, 0 false detections and 0 misses. 6 available position comparisons produce an average error of 219 nautical miles.

At the lead time of 5 days (120 hours), there were 4 hits, 0 false detections and 0 misses. 4 available position comparisons produce an average error of 265 nautical miles.

At the lead time of 6 days (144 hours), there were 3 hits, 0 false detections and 2 misses. 3 available position comparisons produce an average error of 213 nautical miles.

At the lead time of 7 days (168 hours), there were 4 hits, 0 false detections and 1 miss. 4 available position comparisons produce an average error of 402 nautical miles.

At the lead time of 8 days (192 hours), there were 1 hit, 2 false detections and 4 misses. 3 available position comparisons produce an average error of 784 nautical miles.

At the lead time of 9 days (216 hours), there were 1 hit, 1 false detection and 3 misses. 2 available position comparisons produce an average error of 664 nautical miles.

At the lead time of 10 days (240 hours), there were 0 hits, 1 false detection and 4 misses. 1 available position comparison produces an average error of 669 nautical miles.

At the lead time of 11 days (264 hours), there were 1 hit, 0 false detections and 4 misses. 1 available position comparison produces an average error of 720 nautical miles.

At the lead time of 12 days (288 hours), there were 1 hit, 1 false detection and 4 misses. 1 available position comparison produces an average error of 721 nautical miles.

At the lead time of 13 days (312 hours), there were 1 hit, 0 false detections and 4 misses. 1 available position comparison produces an average error of 755 nautical miles.

At the lead time of 14 days (336 hours), there were 1 hit, 0 false detections and 4 misses. 2 available position comparisons produce an average error of 1066 nautical miles.

At the lead time of 15 days (360 hours), there were 2 hits, 0 false detections and 4 misses. 3 available position comparisons produce an average error of 849 nautical miles.

At the lead time of 16 days (384 hours), there were 2 hits, 0 false detections and 3 misses. 3 available position comparisons produce an average error of 863 nautical miles.

At the lead time of 17 days (408 hours), there were 1 hit, 2 false detections and 4 misses. 3 available position comparisons produce an average error of 1029 nautical miles.

At the lead time of 18 days (432 hours), there were 0 hits, 5 false detections and 5 misses. 4 available position comparisons produce an average error of 1441 nautical miles.

At the lead time of 19 days (456 hours), there were 1 hit, 4 false detections and 4 misses. 3 available position comparisons produce an average error of 1172 nautical miles.

At the lead time of 20 days (480 hours), there were 2 hits, 3 false detections and 3 misses. 3 available position comparisons produce an average error of 1017 nautical miles.

Circle coloration scheme

Here are the tracks once again.

July 8, 06Z:

July 10, 06Z:

July 11, 12Z:

July 18, 06Z:

July 19, 06Z:

July 23, 12Z:

July 24, 12Z:

July 26, 12Z:

July 27, 12Z:

July 28, 06Z:

July 29, 12Z:

July 31, 06Z:

August 1, 06Z:

August 2, 12Z:

The complete misses were from the following model cycles:

July 12, 12Z
July 13, 12Z
July 15, 12Z
July 16, 06Z
July 17, 12Z

July 20, 06Z
July 22, 06Z