Ace's Pilot Shop Weather Data
Aviation weather and flight planning, including forecasts, observations, weather maps, DUATS briefings, icing, and turbulence.
Aviation Digital Data Service (ADDS)
Comprehensive user-friendly aviation weather graphics including icing, turbulence, and convection. Also includes a "Flight Path Tool" for pilots.
Aviation Weather Center
The National Weather Service's aviation weather site with official forecast products as well as experimental products.
Base Ops
Aviation Weather for Flight Preparation with TAF Metar Sigmet Radar and Sat-pictures.
Data Transformation Corp DUAT
FAA's Direct User Access Terminal service provides free aviation weather and flight planning for certified pilots in the US.
Enflight
Obtain plain-language weather briefings using exclusive WXpert translation. View up-to-date weather graphics. Helps prepare and file flight plans. Available both on the Web and on mobile PDAs (Palm i705, etc.)
Flying in Europe
Weather information for flying in Europe, including all airport notams, calculations, country information, airport webcams, FBO database, and all aviation abbreviations.
Landings: Aviation Weather
http://www1.drive.net/evird.acgi$pass*15878422!_h-www.landings.com/_landings/pages/wthr/av_weather.h
Large database of aviation specific weather links.
METARTAF Aviation Weather Delivery Service
Send current METARs and TAFS for US airports to any email address
Northwest Airlines Meteorology
Providing weather forecasting products for the aviation industry, including specialized turbulence and thunderstorm forecasts.
Pilot Weather Briefing
Free weather information for pilots, including surface conditions, upper level winds, turbulence, icing, thunderstorms, TAFs and Metars, radar and satellite images.
Pilot's Guide to Aviation Weather Services
An online brochure to help pilots use the "National Aviation Weather System."
SA Weather Service - Aviation
Provides weather services for the aviation industry in Southern Africa. Includes metars, sigmet charts and forecasts.
Upper Midwest Aviation Weather
Central reference for aviation weather resources, focusing on current and forecast conditions in the upper midwest region of the US, including Minnesota, Wisconsin, South Dakota, North Dakota, and Iowa.
Weather Briefing for Pilots
Weather links to various weather information sources for pilots.
Winds and Temperatures Aloft
By selecting one of over 160 continental cities in the U.S.A. or one of 30 cities in Alaska, you can obtain wind direction, speed, and temperature forecasts.
WSI
Provides pre-flight and in-flight weather information. Aviation weather also available online through WSI Pilotbrief.