What do the GO, WATCH, STOP and UNKNOWN lamps mean?

Every saved site on the fleet board at /fleet has one lamp, shown as an icon and a word so it never relies on colour alone: a circle for GO, a triangle for WATCH, an octagon for STOP and a question mark for UNKNOWN. The reason sits beneath the word on each row. Lamps also appear in the instrument panel, on Cab mode, on records and on public boards, and those do not all use the fleet's thresholds. The fleet lamp is recalculated every time the board loads or refreshes, with no smoothing and no memory of the previous lamp. You can filter the board by lamp with the menu labelled Filter fleet lamps.

The fleet lamp compares your site's rule with the forecast across the shift window you set. It uses the primary forecast at your asset height and the ensemble odds that the rule is broken, which are drawn at the nearest ensemble level (10, 80, 100 or 120 m), or always at 10 m for a gust rule. It looks at the hours from now to the end of the shift window, not the whole forecast. Change the hours with the SITE SHIFT menus; see the shift window. The rule itself is set from the pencil on the row; see editing a rule.

The lamp shows STOP if the primary forecast reaches your limit in any hour of the shift, or if the ensemble odds of breaking the rule reach 70% in any hour. The reason reads Primary forecast reaches the limit in the shift. or Ensemble P ≥ 70% in the shift. Exactly 70% counts. A STOP can come from the primary forecast alone even if the odds look low, because the primary check comes first.

The lamp shows WATCH if the odds reach 40% in any shift hour, or if the primary forecast comes within 5 mph of your limit without reaching it. Exactly 40% counts. The five miles per hour band is fixed and the footnote on the board shows it in your own unit. The reason reads Within 5 mph of the limit. or Ensemble P ≥ 40% in the shift., with the near-miss text taking precedence when both apply.

The lamp shows GO, with the reason Inside the limit for the whole shift., when none of the above applies: the primary forecast stays more than 5 mph clear of the limit and the odds stay under 40% throughout the shift. GO means that, on the data available, the modelled wind stays inside the rule you entered. It says nothing about conditions on site, and a site can only show GO when the board has enough data to judge.

The lamp shows UNKNOWN when the board cannot judge, and the row states why: No rule set (with a prompt to add a limit), Forecast unavailable., No forecast hours in the shift window., Ensemble unavailable (odds not evaluated) or Missing data in the shift. Missing data is never treated as calm. A row can also say Odds UNKNOWN or UNKNOWN in its columns when the odds could not be worked out, even though a lamp is shown from the primary forecast. See UNKNOWN versus zero and UNKNOWN and missing data.

The lamp at the top of the instrument panel and on Cab mode has its own thresholds. It reads NO LIMIT until you set one. With a limit it shows STOP when the chosen hour is beyond it, WATCH when within 5 mph, and GO otherwise, then the ensemble can only make it worse: it moves to WATCH when 20% of members break the limit and to STOP at 60%. The live public board uses 40% and 70% over the next 24 hours. So the same site can show different lamps on different screens. Always read the reason, and treat the lamp as a sorting aid and not as permission.

A lamp tells you which sites to look at first. It compares modelled forecasts with a limit you entered from your own documents. It does not replace an on-site instrument, your procedure or the person responsible, and it is never a go-ahead. See reading the fleet board for the other columns.