Find the spoke direction
Each petal aligns with a compass bearing such as north, southwest, or east-northeast.
Directional Reference
Windrose charts show where wind comes from, how often it arrives, and how strong it tends to be.
A windrose, also called a wind rose chart, compresses wind direction frequency and speed into a single compass-shaped graphic. It is used to spot prevailing wind patterns quickly in weather analysis, runway planning, marine routing, and urban design.
- Compass basis
- Direction by bearing
- Spoke length
- Frequency of wind
- Color bands
- Speed classes
Quick Answer
What is a windrose?
A windrose is a circular chart that summarizes how often the wind blows from each compass direction and, in many versions, how wind speed changes within those directions. The longest petals point to the prevailing wind, while shorter petals show less common bearings.
How to Read
Read direction first, then frequency, then speed.
Most wind rose charts can be decoded in a few steps. The same logic works whether the chart is printed in a weather report, attached to a runway study, or used in a climate dashboard.
Compare petal length
Longer petals mean the wind was observed more often from that direction.
Read the color bands
Stacked segments commonly represent wind speed bins, from light breeze to stronger flow.
Check the center note
The middle may report calm conditions, total sample count, or the measurement window.
Common Uses
Windrose charts matter anywhere air movement shapes decisions.
Meteorology
Summarize seasonal wind behavior, compare stations, and identify prevailing directions in climate studies.
Aviation
Support runway orientation and operational planning by revealing the directions pilots will face most often.
Marine and Coastal Work
Understand harbor exposure, route comfort, wave generation, and likely drift conditions.
Urban and Environmental Design
Position openings, plazas, and pollution studies around recurring wind corridors and shelter zones.
Chart Anatomy
The windrose combines compass logic with measured frequency.
- Outer ring: the highest frequency scale on the chart.
- Petal orientation: the compass direction the wind came from.
- Petal length: the share of observations from that direction.
- Color segment: the wind speed class within that directional share.
- Center mark: calm conditions or chart metadata.
FAQ
Short answers to common windrose questions.
What does the longest petal on a windrose mean?
It identifies the direction the wind was observed from most often over the selected time period.
Does a windrose show wind speed?
Many windrose charts do. Color bands or stacked segments usually represent speed classes within each direction.
Can a windrose be seasonal?
Yes. Windroses are often plotted for a full year, a season, a month, or even a specific operational window.
Why is it called a wind rose?
The chart echoes the shape of a traditional compass rose, but the petals are data-driven rather than purely navigational.