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In ForeFlight, runway headings are described relative to Magnetic North, while wind directions are described relative to True North. When winds are nearly parallel to the runway at an airport with a significant magnetic variation, it might seem like ForeFlight is reporting a crosswind component from the wrong direction.

To verify that the crosswind component seen in ForeFlight is correct, follow these steps:

1. With the airport displayed in ForeFlight on the Airports page, find the reported True wind direction and wind speed at the top of the Airport Summary or under Weather > METAR. 
2. Tap Info > Features.
3. Find the Magnetic Variation in degrees East (E) or West (W).
4. Use the Magnetic variation to calculate the Magnetic wind direction:
   • If the variation is °East, subtract it from the True wind direction.
   • If the variation is °West, add it to the True wind direction.
5. Tap Runway.
6. Select the correct runway from the list.
7. Scroll down to the Heading section to find the Magnetic runway heading.
8. Enter the wind speed, Magnetic wind direction, and Magnetic runway heading into an E6B or other flight computer to calculate the crosswind component.
9. Compare your result to ForeFlight’s reported crosswind direction. The values should match. 

EXAMPLE

Pilots at Monterey Regional (KMRY) might expect a right crosswind component listed for runway 28R with winds blowing from 290° at 4 knots. The lack of a crosswind arrow in the Runway entry might seem like an error.

However, you can determine that ForeFlight is correct, and there is no crosswind. Here’s how:

STEP 1. Locate KMRY’s reported True wind direction and speed (290° at 4 knots).

STEP 2. Find KMRY’s Magnetic Variation (15° E).

STEP 3. Calculate the Magnetic wind direction: (290° - 15° = 275°).

STEP 4. Find runway 28’s Magnetic heading (278°).

STEP 5. Enter the following into a flight computer to calculate the wind component.

• Wind speed = 4 knots
• Magnetic wind direction = 275°
• Magnetic runway heading = 278°

STEP 6. Evaluate the results:

ForeFlight subtracts KMRY’s magnetic variation (15°E) from the True wind direction (290°) to calculate a Magnetic wind direction of 275°. This wind blows virtually straight down runway 28 (oriented at 278°), and ForeFlight reports no crosswind. This should align with calculations made on a flight computer.