Chapter 1, Introduction 1-1
1 Introduction
This handbook describes the United States (U.S.) aviation weather program, products, and services. It also
documents weather theory and its application to aviation. The objective of this handbook is to help the pilot
and operator understand the basics of weather, aviation weather hazards, and aviation we ather products.
The information included is not prescriptive. Furthermore, the guidance and recommendations in this
handbook are not legally binding in their own right and will not be relied upon by the FAA as a separate
basis for affirmative enforcement action or other administrative penalty. Conformity with the guidance and
recommendations is solely voluntary and nonconformity will not affect rights and obligations under existing
statutes and regulations.
The handbook is a consolidated source of weather information and, in some cases, best practices to assist
with providing safety for flight.
The visualization of the products discussed in this handbook has evolved over the past decade with the use
of internet websites. The use of static black and white depictions of aviation forecasts is quickly becoming
a thing of the past. Today ’s websites provide the products in color and offer options to select and overlay
multiple pieces of weather information.
Today’s aviation weather website s, including those of the National Weather Service ( NWS), continue to
improve the content and visualization of products. Unfortunately, it is not practical to update this handbook
with every change to a weather product.
Examples of weather products in this handbook represent one way of how they can be visualized on a user’s
viewing device ( e.g., computer, tablet, mobile phone, or cockpit display ). The examples shown in this
handbook are from NWS websites.
This handbook is broken into three parts:
• Part 1: Overview of the United States Aviation Weather Service Program and Information.
• Part 2: Weather Theory and Aviation Hazards.
• Part 3: Technical Details Relating to Weather Products and Aviation Weather Tools.
Part 1: