Cold does something visible to a helium balloon, and it worries people who have not seen it before. Here is what is actually happening.
Why it looks half empty at 10 below
Gas contracts as it cools. The same amount of helium takes up less room at minus ten than it did at seventy.
So on a genuinely cold morning your balloon will look soft and sad, and by afternoon it will have firmed up again. Nothing has leaked. You have simply watched physics happen.
The mistake is topping it off at dawn in January to make it look right, then finding it strained and over-full when the sun comes out. Judge fullness in the warmest part of the day.
What cold does not do
It does not damage polyurethane. Ours stays flexible in cold in a way PVC does not; PVC stiffens and can crack at the fold lines if handled frozen.
The one genuine caution is handling. Do not unfold, fold or force a frozen balloon. If you need to take it down and box it in deep cold, bring it inside first and let it come up to temperature before folding it away.
Running a short season
Realistically, Minnesota is a spring-to-autumn product for most businesses, with a winter run for anyone doing seasonal retail.
That suits the economics fine. A balloon is a one-time $1,526 purchase, not a subscription, so a six-month flying season does not cost you anything extra. It deflates, folds and stores flat in its box for the other six.
Customers report still flying the same balloon after fourteen years, and a Minnesota balloon spends a good chunk of that in storage.
Wind and snow load
The usual rule: over 25 miles per hour forecast, bring it in.
Add one Minnesota-specific note: bring it down before a heavy wet snow, not during. A balloon is not designed to carry accumulated snow on the tether or the envelope, and a storm that starts as rain and turns to snow is the awkward case.
Ask for a quote. Call 1-800-791-1445 or email [email protected] and tell us the size and whether you want it printed.
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