62 GPSMAP 4000 Series Owner’s Manual
Using XM
USinG Xm
Understanding Surface Winds
Wind barbs indicate from which direction the wind is coming. The wind barb is a circle with a tail.
Wind speed is indicated by the different combination of ags that are attached to the tail.
Calm
5 knots
10 knots
15 knots
20 knots
50 knots
Wind Direction
Understanding Wave Height
The Wave Height feature shows wave heights. The wave heights for an area are shown in color
intensities.
Understanding Wave Period
The Wave Period feature provides the time (in seconds) between successive waves.
Understanding Wave Direction
The Wave Direction feature shows the direction in which a wave is moving, as indicated by the
direction of the red arrow.
Viewing Fishing Information
The Fishing view contains current water temperature, surface pressure conditions, and shing
forecasts.
From the Home screen, select Weather > Fishing.
Understanding Surface Pressure
This feature shows pressure isobars and pressure centers. The isobars connect points of equal
pressure. Pressure readings can help determine weather and wind conditions in an area. High
pressure areas are generally associated with fair weather. Low pressure areas are generally associated
with clouds and the chance of precipitation. Isobars packed closely together show a strong pressure
gradient. Strong pressure gradients are associated with areas of stronger winds.
Pressure units are shown in Millibars (mb), Inches of Mercury (in), and Hectopascals (hPa).
