Arizona area residents are bracing for what could be heavy rains at least through Wednesday as Tropical Storm Paine continues to engulf the area.

As of early Monday, the tropical storm was churning southwest of the Baja, California area at winds of up to 90 mph. The storm was expected to make landfall northwest of Baja early Wednesday, by which time its impact could have weakened.

Phoenix in Crosshairs

The Phoenix area is expected to be hardest hit, with rains and storms forecast for throughout the day on Tuesday. In all, meteorologists are forecasting as much as a quarter inch of rain for that area and up to half an inch for the area of Southwest Arizona.

Cooler temperatures are expected for the Phoenix area on Tuesday through Wednesday, but temps were still to rise into the low 90s.

Karl Could Turn to Hurricane

Meanwhile, tropical storm Karl remains on track to strengthen into the next Atlantic hurricane of the season as it circles the area of Bermuda.

"Karl is likely to become a hurricane by the end of this week," said AccuWeather Hurricane expert Dan Kottlowski, adding that the system is slated to rise along the Atlantic beaches as the weekend nears.

In time, Karl is expected to stir along the Caribbean Islands, posing major danger for shipping interests over the next several hours.

American authorities are hoping a cool front will prove enough to push the storm far enough northeast that it skips U.S. soil altogether.

Even if the storm manages to miss the U.S., its domestic effects could still be felt. Swells generated by the hurricane are likely to reach the East Coast and create hazards for swimmers and boaters alike. The routes of freight and cruise ships over the southwestern Atlantic Ocean could be impacted.

The storm could also endanger late-season vacationers hoping to take advantage of the still warm water temperatures before the official change of season.