Online guides to recent severe weather outbreaks including maps, images and analysis (Illinois, US)-:

• April 19th 1996 tornado
• Veteran's Day Lake Effect Snow Storm
• Hurricane Andrew
• Superstorm 1993

• Air masses and fronts
• Clouds and precipitation
• El Niño
• Forces and winds
• Hurricanes
• Hydrological cycle
• Light and optics
• Midlatitude cyclones
• Severe storms
• Weather forecasting

• National Oceanic and Atmospheric Administration weather glossary: Comprehensive index of weather terms for the storm spotter. (US)
• Cloud Boutique Meteorology Program: Explanations and access to detailed pictures of basic cloud forms. (Plymouth State College, US)
• Weather and Climate: Physical processes underlying weather and climate, and applications of fundamental skills (mathematical and interpretive) in environmental science. (Indiana University at Bloomington, US)