The formula
Final score = (Advisory × 0.5) + (Conflict × 0.3) + (Weather × 0.1) + (Health × 0.1), renormalised when a feed is offline.
State Dept + UK FCO levels
Regional violence baseline
Open-Meteo 3-day forecast
WHO DON + GHO indicators
Tier thresholds
Normal precautions; tourism running normally.
Generally safe with localised issues — petty crime, occasional unrest.
Active advisory: avoid specific regions, monitor news daily.
Active conflict, outbreak, or Level 3–4 advisory.
The four signals, explained
Government Advisory
Both governments classify destinations on a 1–4 scale. Level 1 = normal precautions, Level 2 = increased caution, Level 3 = reconsider travel, Level 4 = do not travel. We map those levels to 95 / 75 / 45 / 15 respectively, then average across sources mentioning the country.
Conflict
A baseline derived from ACLED's published violence event density. Calm Pacific and Northern European regions score in the high 90s. Active warzones drop into the teens. We continuously refine this signal toward higher country-level resolution.
Weather & Natural Disasters
We read the capital's current temperature, wind speed, precipitation and the next 72h forecast. Penalties trigger on extreme heat (>35°C), extreme cold (<-15°C), heavy rain (>20mm/day) or strong wind (>40km/h). Calm tropical or temperate readings score in the mid-90s.
Disease Outbreaks
Keyword matches on outbreak titles (ebola, cholera, mpox, marburg, etc.) penalise the score. We layer in long-run health context: annual PM2.5 above 35 µg/m³ flags chronic air-quality risk; life expectancy contextualises baseline health system strength.
Refresh cadence & limits
Country scores are refreshed daily from upstream sources. If a particular source is temporarily unavailable, we retain the last known value and flag it clearly on the country page — no signal is ever silently allowed to inflate a score.
What this is not
GreenLight Travel is an editorial aggregation, not a government service. It cannot replace your own government's advice, your insurer's terms, or the situational awareness of someone on the ground. Treat every score as a starting point — then verify before you fly.