Home heating costs are climbing fast heading into winter, which is bad news for rural families and anyone who heats with propane or oil.

• Propane prices are already up at Midwest suppliers, and heating oil in Massachusetts costs far more than a year ago.
• Tanker traffic carrying liquefied gas is getting squeezed by the Strait of Hormuz closure, tightening supply.
• A strong El Niño points to a colder, snowier winter, which would push demand even higher.
• Locking in a fixed price per gallon or renting a bigger tank now could beat paying winter spot prices.
• Officials insisting supply is "adequate" for grain drying is itself a sign of worry behind the scenes.

Outlook: Expect propane and heating oil bills to keep rising into winter, with price-lock deals disappearing as suppliers pull back.