Does Cold Temperature Really Affect the Level Gauge on a Propane Tank?
Propane is like nearly all other kinds of materials in that it is affected by cold temperatures. The propane gas contracts as the temperature does down. That reduced level of gas inside the tank is reflected by the gauge which reflects the tank level. Normally, this happens whenever a homeowner checks the gauge in cold weather and sees the amount of the tank level before and after delivery. Depending on the climate, the level on the tank might not rise as much as expected.

Propane Tank Level Gauge
The propane tank's gauge shows you what percentage of the tank is full. Normally, tanks are not filled over 80% in order to enable the gas to expand on hot days. For instance, a 500 gallon tank, at a reading of 80 percent at normal temperatures reflects approximately 400 gallons of propane inside the tank. This is around how much can be stored.

Normal Temperatures
The website Propane 101, that is operated by the propane industry, considers an exterior temperature of 60 degrees to be the reference or baseline point. Like for example, if the gauge reads 50 percent of capacity on a day when the temperature is close to 60 degrees, then a 500 gallon tank would contain approximately 250 gallons of propane. If the temperature that same day is much lower than 60 degrees, the gauge would read lower. Similarly, if the temperature is a lot higher than 60 degrees, the gauge would actually read higher since the gas expanded.

Effect of Expansion and Contraction
Based on the information provided by the propane industry web site, the amount of energy contained inside the tank does not really change as the gas contracts or expands. The amount of propane itself has not changed, but only the density of the gas has changed.

Cold-Weather Delivery
If a homeowner orders 100 gallons of propane to be delivered, they would receive 424 lbs. of propane. If the homeowner has a 1000 gallon propane tank, they may expect the gauge to go up by 10% with the delivery of 100 gallons. These numbers will be correct if the temperatures were close to 60 degrees at the time of delivery. If the delivery happened during colder weather, these chillier temperatures would cause a smaller increase reading on the propane gauge.