How the assessments work
This page explains how Bakvind evaluates the flying summary, launch suitability, and thermal quality. The assessments are designed as practical decision support for hang gliding and paragliding, based on local station measurements.
This is a heuristic assessment, not a final answer. Local knowledge, pilot judgement, and a conservative safety margin should always carry more weight.
Principles
The logic is intentionally simple and conservative. Launch suitability is weighted most toward safety, while thermal quality tries to describe whether the air actually looks active and usable. The result is meant as a quick summary of local conditions, not as an automatic go/no-go decision.
Launch suitability
Launch suitability is mainly based on wind direction relative to site sectors, mean wind, gusts, gust spread, rain, and how stable the direction is. If the wind is outside a usable sector, if it is raining, or if the wind becomes too strong, the assessment should clearly move toward caution or avoid.
Aligned is used when the direction is inside the green sector and the wind looks manageable. Caution is used when wind becomes noticeable, gusts rise clearly above mean wind, or direction shifts more than desired. Strong is used when mean wind is above 8 m/s, or when gusts rise more than 2 m/s above that threshold. Avoid is used for a red sector, outside a usable sector, or when rain is falling at launch.
Thermal quality
Thermal quality describes how organized and usable the air looks, not just how strong the wind is. It uses signs of surface heating, temperature trend, dew point spread, mean wind, gusts, and direction changes.
Clean requires clear thermal potential, limited gust spread, and relatively stable direction. Usable is used when several signals point the right way, but conditions do not look fully organized. Rough is used when wind is gustier, direction shifts more, or the wind is strong enough that lift will likely feel less organized. Flat is used when limited surface heating, rain, or a very weak thermal signal suggests that the air is not really working.
Flying summary
The flying summary combines launch suitability and thermal quality. Its main job is to prevent promising thermal signals from hiding poor or unsafe launch conditions.
Avoid right now is used when launch conditions are outside sector, in a hazard sector, in rain, or the wind is too strong. Good thermal window requires good launch direction, high thermal score, and clean air. Flyable but rough is used when there may be lift, but the wind looks disorganized. Stable / weak is used when thermals look suppressed or flat. Watch conditions is used when conditions are partly promising, but not clear enough for a green light.
Sensors and signals
Bakvind uses what the local station actually measures: wind speed, gust, wind direction, temperature, dew point, humidity, pressure, light, UVI, and rain. Short history windows are also used to see whether temperature is rising and whether the wind looks stable or changeable.
Current key thresholds
Some thresholds are made explicit to keep the assessments easy to understand. Mean wind above 5 m/s moves the assessment toward caution. Mean wind above 8 m/s is treated as strong. Gusts are allowed about 2 m/s more than the mean-wind thresholds before they move the assessment to the same level. Rain at launch always counts negatively, and a large spread between mean wind and gust is treated as a sign of more turbulent air.