Verification of tracks made of Gonzalo

I made seven tracks of Tropical Storm Gonzalo, before it was assessed as a tropical cyclone. I made three more tracks after that point. Additionally, within 480 hours of cyclogenesis, there were nine instances, when I missed cyclogenesis entirely. In the tracks, longevity and peak intensity were generally overestimated.

As of this analysis, best track positions are available July 19, 12Z thru July 25, 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 seven tracks (made before operationally recognized cyclogenesis), formation times ranged between July 12, 06Z and July 30, 18Z. Average was July 18, 01Z and median was July 17, 12Z.

In the 19 cases (10 tracks, before the tracks and data agreed, that tropical storm would remain the peak intensity, and 9 complete misses), peak intensity ranged between Category -2 and  Category 5. Average was Category 0.68 and median was Category 0.

In the ten tracks (made before operationally recognized degeneration into remnant low), dissipation times ranged between July 21, 12Z and August 5, 12Z. Average was July 30, 08Z and median was July 31, 00Z.

At the lead time of 1 day (24 hours), there were 3 hits, 0 false detections and 0 misses. 3 available position comparisons produce an average error of 74 nautical miles.

At the lead time of 2 days (48 hours), there were 2 hits, 3 false detections and 1 miss. 4 available position comparisons produce an average error of 105 nautical miles.

At the lead time of 3 days (72 hours), there were 2 hits, 3 false detections and 1 miss. 3 available position comparisons produce an average error of 132 nautical miles.

At the lead time of 4 days (96 hours), there were 1 hit, 4 false detections and 2 misses. 2 available position comparisons produce an average error of 196 nautical miles.

At the lead time of 5 days (120 hours), there were 2 hits, 3 false detections and 2 misses. 2 available position comparisons produce an average error of 285 nautical miles.

At the lead time of 6 days (144 hours), there were 2 hits, 3 false detections and 2 misses. 2 available position comparisons produce an average error of 373 nautical miles.

At the lead time of 7 days (168 hours), there were 1 hit, 4 false detections and 3 misses. 1 available position comparison produces an average error of 556 nautical miles.

At the lead time of 8 days (192 hours), there were 1 hit, 4 false detections and 2 misses. 1 available position comparison produces an average error of 670 nautical miles.

At the lead time of 9 days (216 hours), there were 0 hits, 4 false detections and 3 misses. No available position comparisons.

At the lead time of 10 days (240 hours), there were 0 hits, 4 false detections and 3 misses. No available position comparisons.

At the lead time of 11 days (264 hours), there were 0 hits, 3 false detections and 3 misses. No available position comparisons.

At the lead time of 12 days (288 hours), there were 0 hits, 2 false detections and 4 misses. No available position comparisons.

At the lead time of 13 days (312 hours), there were 0 hits, 2 false detections and 3 misses. No available position comparisons.

At the lead time of 14 days (336 hours), there were 0 hits, 1 false detection and 3 misses. No available position comparisons.

At the lead time of 15 days (360 hours), there were 0 hits, 1 false detection and 3 misses. No available position comparisons.

At the lead time of 16 days (384 hours), there were 0 hits, 1 false detection and 2 misses. No available position comparisons.

At the lead time of 17 days (408 hours), there were 0 hits, 2 false detections and 2 misses. No available position comparisons.

At the lead time of 18 days (432 hours), there were 0 hits, 5 false detections and 1 miss. No available position comparisons.

At the lead time of 19 days (456 hours), there were 0 hits, 4 false detections and 0 misses. No available position comparisons.

At the lead time of 20 days (480 hours), there were 0 hits, 4 false detections and 0 misses. 1 available position comparison produces an average error of 319 nautical miles.

Circle coloration scheme

Here are the tracks once again.

June 24, 06Z:

June 25, 06Z:

June 26, 06Z:

June 29, 12Z:

July 17, 12Z:

July 19, 06Z:

July 20, 06Z:

July 22, 06Z:

July 23, 12Z:

July 24, 12Z:

The complete misses were from the following model cycles:

July 7, 12Z
July 8, 06Z
July 10, 06Z
July 11, 12Z
July 12, 12Z

July 13, 12Z
July 15, 12Z
July 16, 06Z
July 18, 06Z