Description
Round supplied wind speed to a nominal wind-barb decomposition.
Atmospheric values depend on pressure order, vertical datums, moisture definitions and reference conditions. Specific humidity uses moist-air mass as its denominator, whereas mixing ratio uses dry-air mass. A pressure-order flag differs from a temperature inversion, and a logarithmic-pressure weight can represent extrapolation.
Round supplied wind speed to a nominal wind-barb decomposition.
When to use this tool
Use Wind Barb Speed Rounding Code when you already have speedKnots and need to round supplied wind speed to a nominal wind-barb decomposition.
How to use the tool and how it works
- Enter speedKnots. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read roundedKnots, pennants, fullBarbs, halfBarb. Inspect halfBarb before interpreting the associated values.
Require speedKnots>=0; halfUnits=Math.round(speed/5) must be safe. Return halfUnits*5, floor(halfUnits/10) pennants, floor((halfUnits%10)/2) full barbs and the odd remainder as a half barb.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| speedKnots | Speed Knots | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| roundedKnots | Rounded Knots | Required. Finite number. |
| pennants | Whole nominal 50-knot units after nearest-five-knot rounding. | Required. Safe integer. |
| fullBarbs | Whole nominal 10-knot units remaining after pennants. | Required. Safe integer. |
| halfBarb | True for one remaining 5-knot unit. | Required. Boolean. |
{
"input": {
"speedKnots": 63
},
"output": {
"roundedKnots": 65,
"pennants": 1,
"fullBarbs": 1,
"halfBarb": true
}
}Limitations and assumptions
- Halfway speeds round upward, and each pennant/full/half represents 50/10/5 knots. This does not encode wind direction, calm-circle policy, gusts or an actual observation.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated profile and station data with the complete atmospheric model. Preserve datum, humidity and pressure conventions and assess uncertainty before interpreting local terms as an observed layer, state or forecast.
References
Similar or alternative tools
- Radiosonde Pressure Inversion Pair
Compare supplied upper- and lower-level pressures.
- Station Wind Height Reference Label
Qualify an explicit station wind-measurement height by supplied datum wording.