Daily Routing Brief — 2026-05-30
Generated 2026-05-30T14:43:51.450352+00:00 · Newport→Bermuda 2026 · T−20 days · « all briefs
Regime: PRACTICE + OCEAN-TRACKING — T−20 days. No atmospheric model reaches race day yet (~7-day horizon). The codes below are crew practice, not a June-19 forecast. The genuinely predictive signal this far out is the Gulf Stream — track its evolution below.
PRE-RACE PRACTICE ONLY — not for use during the race
These are pre-race research / practice reps. Per RRS 41 (2026 NOR) a boat shall not receive routing assistance from shore — including AI-generated — while racing. This page stops updating before the June 19 start; do not open it from the boat once racing.
Headline
Current forecast window most resembles 2012 (W-PF/W-BH/W-BH, score 5.10).
- Winner that year: Carina (Reichel/Pugh design) — line honors basis
- What won: Simple execution near rhumb; ~2 jibes + 2 tacks for 636 nm
- Winning tactics: T-RH T-PF T-CL
- Lesson: Benign Stream year. Execution beats positioning. Low maneuver count wins reaching races.
- Best corridor that year: RHUMB
Per-period classification (current window)
Start anchor: 2026-05-30T00:00:00+00:00 · horizon +383 h
| period | code | conf | GFS wind/gust | ECMWF wind/gust | ICON wind/gust |
|---|---|---|---|---|---|
| P1 start / coastal | W-PF | MEDIUM (67%) | 15.4/37.1 kn | 13.5/26.8 kn | 16.3/30.1 kn |
| P2 Gulf Stream crossing | W-BH | HIGH (100%) | 21.5/27.2 kn | 20.7/32.1 kn | 21.1/33.0 kn |
| P3 Bermuda approach | W-PF | HIGH (100%) | 5.9/10.3 kn | 6.2/13.4 kn | 7.1/14.2 kn |
Codes are atmospheric only and link to the analog framework. Wind/gust in knots. Confidence = model agreement. See the method.
Trend (day over day)
vs 2026-05-29 (T−21):
- Headline analog changed: 2018 → 2012.
- Period codes: P1 W-LA→W-PF; P2 W-CF→W-BH.
- Model agreement: 78% ↑ 89%.
- Gulf Stream snapshot unchanged (2026-05-31).
- Crossing SST: 22.2→22.3 °C →, north-wall jump +6.1°C.
- Peak corridor wave: 2.4→2.0 m ↓.
Convergence: race day not yet in model horizon — convergence tracking begins automatically once it is (~T−7).
Analog ranking (period-aware)
| rank | year | score | P1/P2/P3 | best corridor |
|---|---|---|---|---|
| 1 | 2012 | 5.10 | W-PF/W-BH/W-BH | RHUMB |
| 2 | 2024 | 2.55 | W-PF/W-RC/W-BH | RHUMB |
| 3 | 2022 | 2.55 | W-PF/W-CC/W-BH | EAST |
| 4 | 2016 | 2.55 | W-PF/W-CC/W-PL | RHUMB |
2014 excluded as seed data. Years link to their winner-route writeups.
Gulf Stream (observed — the real signal this far out)
Latest local snapshot: 2026-05-31 (1 days old)
Clearest satellite SST pass for 2026-05-31 (Rutgers RUCOOL). Full imagery set + Frank Bohlen's note: data/gulfstream-monitor/2026-05-31/.
A cold-core ring or meander near the rhumb persists for weeks, so today's Stream state genuinely informs June 19 — see the corridor decision page. Stream codes (W-RC/W-CC/W-WE/W-AC) come from this observed data, not the atmospheric forecast.
Crossing corridor with the 2026-05-30 Stream walls + eddy (0 days old), frozen for this brief.
Full interactive planning map — all six past corrected-time winners' tracks over the corridor (toggle layers).
Data sources
- Forecast (wind · gust · pressure — GFS·ECMWF·ICON): Open-Meteo · full list in the Sources & Tools catalog.
- Gulf Stream SST: NOAA OPC NCOM · Rutgers RUCOOL · NASA SPoRT.
- Gulf Stream currents: NOAA OPC RTOFS · AOML altimetry.
- Expert read: Frank Bohlen's Gulf Stream notes.
Sea state & ocean (numeric — Open-Meteo Marine)
Near-term (next 24 h) means along the corridor. SST and waves are reliable; ocean current is a COARSE model that understates the Gulf Stream (2–4 kn) and cannot see rings or meanders — trust the Stream imagery for structure.
| waypoint | SST | current | wave |
|---|---|---|---|
| start | 13.4 °C / 56 °F | 0.6 kn @ 154° | 1.8 m / 6 s |
| shelf | 16.2 °C / 61 °F | 0.6 kn @ 123° | 1.7 m / 7 s |
| stream | 22.3 °C / 72 °F | 0.5 kn @ 78° | 2.0 m / 7 s |
| post_stream | 22.2 °C / 72 °F | 0.4 kn @ 195° | 1.9 m / 7 s |
| approach | 23.0 °C / 73 °F | 0.8 kn @ 138° | 1.8 m / 8 s |
North wall: SST jumps +6.1 °C from the shelf (16.2 °C) to the crossing (22.3 °C) — a clear Gulf Stream front signature.
Sea state: peak corridor wave ~2.0 m.
Wind-with-current at start, shelf, stream — flow and breeze aligned, so seas should run smoother/longer there than the wave height alone suggests.
Race-day horizon
Race day is T−20 — beyond the ~7-day model horizon. The classifier correctly declines (no fabricated race-day codes). Convergence tracking begins automatically when race day enters the window (~T−7).
Sources: forecast — Open-Meteo (GFS/ECMWF/ICON, no key). Analogs — framework + winner routes + tactics. Gulf Stream — scripts/gulfstream_monitor. Method — forecast analog matcher. Pipeline — scripts/daily_brief.py.