Meteorology · Tropical Cyclones — 34-Knot Rule / Avoidance
A widely used guideline for avoiding tropical cyclones is to:
- AIgnore the forecast track
- BPass as close to the eye as possible
- CSteer directly for the storm center to get through quickly
- DStay well outside the forecast 34-knot wind radius, allowing a wide margin for forecast error (e.g., the 1-2-3 rule)✓ Correct
Explanation
Mariners keep clear of the forecast gale (34-kt) wind field with a generous buffer for track error. The 1-2-3 rule adds roughly 100/200/300 NM to the 34-kt radius at 24/48/72 hours to define a danger area to avoid. Early, decisive action to stay on the safe side is the key to avoidance.
Authority: NHC; Bowditch (Pub. No. 9)
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