Garmin GXM 30 Surface Pressure

XM WEATHER FEATURES > SURFACE PRESSURE

Surface Pressure

This feature displays 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 that are packed closely together show a strong pressure gradient. Strong pressure gradients are associated with areas of stronger winds. Pressure units can be displayed in Millibars (mb), Inches of Mercury (in), and Hectopascals (hPa).

Pressure Isobars

Strong Pressure Gradient

13	GXM 30 XM Radio Smart Antenna Owner’s Manual

Contents

Page Page Warning Caution INTRODUCTION Preface Terminology used throughout this manual Product Registration XM WX Weather and XM Radio ID Introduction Getting Started XM WX Weather Features Appendix Unit Overview GETTING STARTED Connecting the GXM 30 to a Garmin Unit Subscribing to XM WX Weather and Radio Service Level XM WX WEATHER FEATURES Displaying Weather Information MENU Show Weather ENTER NEXRAD Radar Satellite Mosaic Lightning Storm Cells Hurricanes Surface Winds Winds Aloft Surface Pressure Fronts Visibility County Warnings Water Temperature Wave Period Wave Direction Wave Height Marine Warnings Buoy Reports METAR AIRMET SIGMET TFR Echo Tops Freezing Level Forecast TAF XM Radio APPENDIX Speciﬁcations Physical Speciﬁcations Power Performance Feature Data Broadcast Frequency NEXRAD Overview NEXRAD Description NEXRAD Abnormalities NEXRAD Limitations NEXRAD Intensity FCC Compliance Limited Warranty Online Auction Purchases: International Purchases: Software License Agreement XM Satellite Radio Service Agreement Weather Data Warranty TFR Data INDEX Page Page Garmin products, visit the Garmin Web site at www.garmin.com