WEATHER:

The weather on San Cristobal varies enormously with elevation, although very little with season.  The temperature, while usually at a comfortable 74 degrees at sea level (lower than normal equatorial temperatures due to the cool Humboldt ocean current), drops about 1 degree per 1000 feet elevation.  As elevation increases, so does precipitation.  The average high in January is 82, while the average high in August is 75.²⁰

CLIMATE:

“The Galapagos Islands' climate is strongly influenced by oceanic currents. The relatively cold Humboldt current flows around and through the islands during most of the year. This current meets the warm tropical waters from the Gulf of Panama at a point north of the Archipelago. From January to April the convergence moves south and the warm current surrounds the islands. There are two seasons due to the shifting of the currents. The dry season, caused by the Humboldt current, is characterised by cool temperatures (17°C-22°C), a fairly persistent fog or 'garua' that envelopes the highlands of the larger islands in mist and drizzle, and south-easterly winds. The variable short, hot season, caused by the warm current, is characterised by warmer temperatures (23°C-27°C), light easterly winds and seasonal rains. Approximately every four years, heavy rainfall occurs during this season. Temperatures generally decline by some 0.9°C for every 100m altitude. At the wettest place at sea level, the mean annual precipitation is 356mm, whilst at 200m above sea level the equivalent figure is 1092mm (UNDP/UNESCO, 1974)”

 --Taken directly from http://www.wcmc.org.uk/protected_areas/data/wh/galapago.html

These data tables, taken from http://www.galapagosislands.com/html/galapagos_climate.html, show the rainfall levels at sea level.  June – December is the “cool season”, while January – May is the “warm season”.

Average Rainfall and Average Daily Temperature Month by Month

Average Rainfall and Average Daily Temperature Month by Month

TIDES:

This chart, from http://www.mobilegeographics.com:81/locations/5536.html, shows the tides on the Southern tip of San Cristobal.  The average tide is about 5.5 feet.