Wind, cold and rain: how weather moves the temperature

A pellet grill has to replace every bit of heat it loses. Cold air and wind take heat away faster, so the grill works harder and the temperature can wander more.

What the makers say about weather

One grill maker lists cold weather among the things that affect the grill's temperature. Its definition of normal behavior is tied to a typical, good-weather day, when it says the grill should fluctuate no more than 15°F either way.¹

Note what that implies. The stated range is for good weather. It isn't a promise for a gale or a freezing morning.

A pellet maker says that in the cold months the temperature might swing low, especially with high winds or snow.²

Why wind and cold hurt

The grill makes heat by burning pellets, and it measures the result with one sensor. If wind carries heat off the surface of the cooker, the sensor sees the temperature fall and the controller feeds more. The page on the controller shows that loop.

A smarter controller helps. A PID controller adjusts how fast it feeds by learning how the grill responds under current conditions.³ Even so, it can't make heat the fire hasn't produced yet.

The pattern, then: heat leaves quicker, the controller reacts after the fact, and swings can widen. This is reasoning from the mechanism, not a measured result, so your own grill may behave differently.

Humid days run the other way

Cold isn't the only weather effect. One pellet maker says moisture in the air on humid days will make pellets burn more quickly, meaning higher temperatures.² It adds that on hot, humid days the grill might swing past the set temperature before returning to it.²

Rain is a separate question. Rain on the grill and rain on the pellets are different problems, and wet pellets are covered with pellet and feed troubles. Follow your manual's guidance on keeping the grill and fuel dry.

What you can do

The sources give a few simple steps.

• Shield the grill from intense winds, or use an insulated grill blanket.²
• Check that the stack cap, also called the chimney cap, is properly adjusted.⁴
• If the grill struggles to stay up to temperature in extremely cold weather, one maker suggests lowering the chimney cap.⁴

That last tip is one maker's advice for its own grills. Chimney and vent settings differ between models, so check your manual before changing anything. Use a blanket only if your model's manual allows it. A cover near a hot grill raises safety questions this site can't answer.

Where to put the grill

A windbreak helps, but the grill still needs open air around it. Never move a grill into a garage, shed, tent or porch to dodge the weather. A pellet grill burns fuel, and carbon monoxide from burning fuel in a closed space can kill. Keep clearances from walls and anything that burns as your manual says.

Fire bans and burning rules come from your local fire authority, not from this site. Check theirs before you light up in dry or windy conditions.

What to expect

On a bad day, plan for more drift and more time to settle. If swings look wild even on mild days, weather isn't the cause. Look at pellets and feed, ash and, last, telling a fault from normal drift.