Forecasts of a hybrid storm blending remnants of a post-tropical storm Sandy with already severe weather over Ontario are prompting warnings from relief workers to brace for an emergency by stocking up with at least three days' worth of supplies.

The Canadian Red Cross issued a release Sunday urging Ontario families to ensure they have enough food and water to sustain themselves for at least 72 hours as the weather system, which is lashing the U.S. east coast and North Carolina, continues to lumber towards Ontario with wind speeds of up to 130 km/hr.

Blackouts and flooding could affect many parts of the province, according to Environment Canada. Evacuations are also possible due to the system, which has earned the moniker "Frankenstorm" — a reference to the mix of meteorological factors comprising it.

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"Be prepared to take care of yourself and your family for at least 72 hours in an emergency," Mike Morton, the Canadian Red Cross director of disaster management in Ontario, said in a release.

"By taking some time now to store emergency food, water and other supplies, you can provide for your entire family during a power outage or evacuation."

Among items to consider for an emergency kit are:

  • Four litres of water per person for each day of a 72-hour period (two litres for drinking, and two litres for washing)
  • Enough non-perishable or canned food for each person for 72 hours, as well as enough food for pets
  • A manual can opener
  • A crank or battery-operated flashlight, with extra batteries
  • A crank or battery-operated radio, with extra batteries
  • Spare keys for the house and car
  • A first aid kit
  • Cash in small bills, in case power outages restrict the use of bank machines
  • Other special needs items such as medications, baby formula, diapers and equipment for people with disabilities

The Canadian Red Cross recommends keeping the supplies in easy-to-carry containers, such as rolling suitcases, so they can be easily transported in the event of an evacuation.

CBC weather specialist Craig Larkins said Sandy, which is still a Category 1 hurricane, is 1,300 kilometres wide, making it the second-largest tropical storm in the Atlantic since 1988.

Eastern Ontario to bear brunt of weather

"That says a lot — it could actually still take the No. 1 spot," Larkins said Sunday, adding that Sandy will be downgraded to a post-tropical storm as it pushes towards Ontario.

Environment Canada forecasts the worst of the rain and winds to smack the province Monday night and into Tuesday morning. Gusts are expected to be around 90 to 100 km/hr, with the worst winds expected around southeastern and eastern Ontario and in the Hamilton, Niagara and Sarnia regions.

"Toronto will be seeing its fair share of rain as well, part of that separate disturbance that's moving through the province right now, but again the two will merge, so 50 millimetres [of rainfall in Toronto] will climb possibly over the 100 millimetre mark by Wednesday," Larkins said. "So it's a three-day event when we're talking rainfall."

People with travel plans are advised to make alternate arrangements if they're concerned about the dangers of possible downed electrical wires or flooded roads.

Travellers are also being advised to check the status of their flights in the coming days. Air Canada is reminding customers to look up their flights if they plan to head to Newark, Laguardia, JFK, Philadephia, Washington, Boston and Baltimore airports.

Similarly, Porter Airlines is reminding people to check for delays or cancellations for flights to Newark Boston and Washington in the days ahead.

For more information on emergency preparedness ahead of the severe weather, visit the Canadian Red Cross website.