The Boquete Weather site has an excellent list of links on many topics, including books, software, climate, and weather. There is no need to duplicate it here - go straight there for as complete a reference as you're likely to want.
Here's a short list of links, several of which are on the Boquete Weather list, that may be of interest to you.
- Accuweather
- Weather Underground
- National Weather Service (from NOAA)
- Department of Meteorology Weather for Panama (in Spanish, with some English terms)
- Multimap weather for Chiriqui (A map of Chiriqui is at the top of the page. Scroll down for forecast.)
- National Weather Service (from NOAA)
- Climate (Wikipedia)
- World Climates
- Weather (Wikipedia)
- Wind - The Beaufort Scale (Wikipedia)
- Rain (Wikipedia)
- Humidity (Wikipedia)
- Dew point (Wikipedia)
- El Niño - Basic Introduction - University of Illinois
- El Niño-Southern Oscillation - ENSO (Wikipedia)
- El Niño and Panama Weather - [from A Neotropical Savanna Blog]