Forecast hour +6
Tue 15 Sep, 08:10
Generated 02:17Weather detail
- Forecast assessment
- Marginal because upper wind range reaches 18.0 kt.
- Wind change
- Falling (-3.4 kt)
- Direction-change risk
- 100%
- Weather regime
- Showery / unstable
- Provider agreement
- Moderate agreementSource wind spread 3.6 kt; direction spread 60°.
- Selected sources
- Met Office 85%Corrected 15%
Gust probability
18+ kt95%
20+ kt92%
25+ kt73%
30+ kt52%
TBSC course selection
Short course255° magnetic
Why this course set?Short selected because the forecast mean is 15.9 kt and gust 22.5 kt, outside the Force 3-4 band; the card uses Short for Force 1-2 or Force 5 conditions.The 261 degree true forecast converts to approximately 262 degrees magnetic and uses the nearest 15 degree matrix column: 255 degrees.
| Fleet | Course |
|---|---|
| Oppy 2 | 1Y |
| Optimist | 3 |
| Feva | 8 |
| Slow Misc | 8 |
| Myth | 8 |
| Misc | 20 |
| 1/2 Rater | 20 |
| Start | G/W |
Wind-based selection; shorten for poor visibility, rough sea or other race-management concerns.
Trearddur Bay Sailing Club
Sailing area
Tue 15 Sep, 08:10 · Wind W 261 deg T at 15.9 kt, gust 22.5 kt · Short course, 255 deg magnetic
Course overlay ready
Course 1YOppy 2Route diagram referenced as page 27 but not included in the supplied scan
Why: The 2026 selector assigns Course 1Y to Oppy 2 for this course length and magnetic-bearing column. Its route refers to page 27, which was not included in the supplied scan.
Course 3Optimist4 rounds · Outer Bay · start G/W
Why: The Short matrix at 255 degrees magnetic assigns Course 3 to Optimist. The normal published mark sequence applies. The route starts at the midpoint of the G/W line, uses Outer Bay as its Bay Mark and finishes at the midpoint of the white line.
Course 8Feva2 rounds · Green Bay · start G/W
Why: The Short matrix at 255 degrees magnetic assigns Course 8 to Feva. The normal published mark sequence applies. The route starts at the midpoint of the G/W line, uses Green Bay as its Bay Mark and finishes at the midpoint of the white line.
Course 8Slow Misc, Myth2 rounds · Outer Bay · start G/W
Why: The Short matrix at 255 degrees magnetic assigns Course 8 to Slow Misc, Myth. The normal published mark sequence applies. The route starts at the midpoint of the G/W line, uses Outer Bay as its Bay Mark and finishes at the midpoint of the white line.
Course 20Misc1.5 rounds · Green Bay · start G/W
Why: The Short matrix at 255 degrees magnetic assigns Course 20 to Misc. The normal published mark sequence applies. The route starts at the midpoint of the G/W line, uses Green Bay as its Bay Mark and finishes at the midpoint of the white line.
Course 201/2 Rater1.5 rounds · Inner Bay · start G/W
Why: The Short matrix at 255 degrees magnetic assigns Course 20 to 1/2 Rater. The normal published mark sequence applies. The route starts at the midpoint of the G/W line, uses Inner Bay as its Bay Mark and finishes at the midpoint of the white line.
The blue wind arrow points downwind; its label states the direction the wind comes from. Each coloured course begins at the midpoint of its selected Red or G/W start line and ends at the midpoint of the white finish line. Coloured arrowheads show the order of travel. Lines show the mark sequence once; follow the number of rounds in the key. Published port/starboard rounding instructions remain authoritative.
Forecast sources
| Source | Wind | Gust | Direction |
|---|---|---|---|
| Local | 19.2 kt | 34.8 kt | SSW 201° |
| Corrected | 15.6 kt | 23.3 kt | W 261° |
| Met Office | 15.9 kt | 22.4 kt | W 261° |
| Persistence | 19.2 kt | 34.8 kt | SSW 201° |
| Residual Shadow | 17.3 kt | 22.3 kt | W 261° |
Guidance only. The race officer's decision, current observations, sea state, visibility, tide, official warnings and local safety procedures take precedence over this experimental forecast.