Products Last Updated 2013 APR 23 06UTC
|Tropical Depression / Tropical Storm||Hurricane|
- TC FORMATION AREAS OF INTEREST:
- Identifies regions of relatively-enhanced summation TC formation probability (see below). To dinstinguish between TC formation and non-formation cases, uses nearby TC formation (see below). Hence, provides a broad-scale "first guess" at areas with the potential for TC formation. The threshold summation probability values that define each potential category were chosen so that 100%/75%/25%/5% of dependent sample set cases meet or exceed the threshold values. Basins were treated independently, so corresponding dependent sample set occurrence frequencies may vary by basin.
| TC Formation Area
of Interest Category
| Occurrence Frequency
(ATLC / EPAC / WPAC)
| Dependent Cases
- Nearby TC Formation
- Describes TC formation that occurs within 20° of a given point. This is less stringent than the 5° criterion used by the main TC Formation Probability product.
- Summation TC Formation Probability
- The sum of the TC formation probabilities at all grid points within a 20° lat by 20° lon subregion centered on that point.
- Occurrence Frequency
- For all points exceeding a given summation probabilty threshold, the percent of those cases that resulted in a "nearby" TC formation (as defined above).