Bearded Dragon Temperature Guide

San Francisco’s naturally cool, foggy climate presents unique challenges for bearded dragon owners. Getting the temperature and humidity right in your bearded dragon’s enclosure is the single most important thing you can do for their health. As an exotic veterinary assistant who has cared for many bearded dragons, here’s what you need to know.

The Right Temperature Ranges

Bearded dragons are desert reptiles from central Australia. They need a clear temperature gradient — a hot basking spot on one side and a cooler retreat on the other.

Why This Matters

Bearded dragons are ectotherms — they regulate their body temperature by moving between warm and cool zones. Without a proper gradient:

• Too cold: Digestion slows or stops, leading to impaction and illness
• Too hot: Overheating, stress, and dehydration
• No gradient: The dragon can’t thermoregulate, causing chronic stress

San Francisco-Specific Considerations

San Francisco’s average indoor temperature hovers around 60-68°F, which is well below what bearded dragons need. This means:

• You’ll likely need a ceramic heat emitter (CHE) for nighttime warmth, especially in the foggy Outer Sunset, Richmond, and Parkside districts
• Your basking bulb may need to be higher wattage than guides recommend for warmer climates
• Monitor with a digital thermometer with probe (not stick-on strips — they’re inaccurate by 10-20°F)
• Consider a thermostat to prevent overheating if your home warms up during rare heat waves

Humidity Levels

Bearded dragons need low humidity: 30-40% relative humidity is ideal. San Francisco’s natural humidity averages 70-80%, so you’ll need to actively manage it.

Tips for controlling humidity:

• Use a screen-top enclosure for maximum ventilation
• Avoid placing the tank in bathrooms or kitchens
• Use a dehumidifier in the room if needed during winter months
• Don’t mist the enclosure — unlike tropical reptiles, bearded dragons don’t need extra moisture
• Provide a shallow water dish but don’t leave standing water in large quantities

What happens if humidity is too high:

• Respiratory infections (wheezing, mucus)
• Skin infections and abnormal shedding
• Fungal growth in the enclosure

UVB Lighting

Bearded dragons require 10-12 hours of full-spectrum UVB lighting daily to metabolize calcium. Without it, they develop metabolic bone disease (MBD), which causes soft bones, tremors, and eventually paralysis.

Setup tips:

• Use a tube-style UVB bulb (T5 or T8) that spans 2/3 of the enclosure length
• Replace UVB bulbs every 6 months — they lose effectiveness before they burn out
• The basking spot should be 6-8 inches from the UVB source (for T5) or 4-6 inches (for T8)
• UVB does not pass through glass — if your bulb is above a glass top, it’s not reaching your dragon

For a complete guide to reptile environmental needs, see my Reptile & Amphibian Care Guide.

Equipment Checklist

• Digital thermometer with probe (basking and cool side)
• Hygrometer for humidity monitoring
• Basking bulb (wattage depends on enclosure size)
• Ceramic heat emitter for nighttime warmth
• Thermostat for heat regulation
• T5 or T8 UVB tube light
• Timer for consistent light cycles

When Something Looks Wrong

If your bearded dragon shows any of these signs, check their environment first — and if temps and humidity are fine, see an exotic vet:

• Black beard stress marks that persist all day
• Lethargy or sleeping on the cool side
• Refusing food for more than a few days
• Sunken eyes (dehydration)
• Rubbery jaw or trembling limbs (MBD)

Going on a trip? I maintain precise temperature gradients, humidity levels, and UVB schedules for every reptile I care for. Learn about my in-home reptile care and reptile boarding in San Francisco. Read more: How to Prepare Your Reptile for Pet Sitting.