Hurricane Dennis picked up strength yesterday as it moved sluggishly toward the Carolina coast, a tight cloudy spiral that could menace the mid-Atlantic region and bring help to a Washington area suffering through drought.

Where the storm will make landfall, if it does, is still an open question among the meteorologists tracking it. But the early odds are good that Dennis, plodding northwest from its staging area southeast of the Bahamas, will arrive somewhere along the North Carolina coast late this weekend. Officials there urged residents and vacationers to begin buying batteries, bottled water and propane in case it does.

There's even a 3 percent chance that Dennis will make landfall at Ocean City, Md., laden with much-needed rain and packing winds exceeding 80 mph. For a Washington region plagued by drought, this hurricane season brings the question of whether to root for the dangerous, rain-heavy storm to arrive or pray it strays out to sea.

"You can get it all at once with a tropical storm," said Melody Paschetag, a National Weather Service hydrologist. "The downside is you could have major flooding, property damage, and even the death of people."

Across the Northeast, heavy rains complicated morning commutes and evening plans yesterday as the parched region received a daylong soaking. In New York City, hundreds of thousands of commuters struggled to work as torrential rains swamped roads and subways..

As Dennis drifted toward the eastern United States, Hurricane Cindy appeared headed out to sea with little potential to reach land. But before departing, Cindy was powerful enough to drain the life out of nearby Tropical Storm Emily, which was downgraded to a tropical depression yesterday as it lingered south of Florida.

Whether Dennis lands within an afternoon drive of Washington or farther south, recent history suggests that the District and its suburbs could get some heavy rain. Three years ago, Hurricane Fran landed in lower North Carolina, then swept northward over Washington days later with enough rain to flood the Potomac River, swamp local roads and drive people from homes in Virginia and Maryland.

"Dennis is still a good three days a way, but I do suspect it will probably hit North Carolina," said Gary Gray, a meteorologist with an online weather service tracking the storms. "Based on the models, I would say the Washington area will be getting rain from this."

How much more rain a hurricane might drop is directly proportional to how slowly it moves, and at this stage, Dennis is creeping along at a snail's pace. Hydrologists say that although a prolonged period of steady, soaking rain is the best way to emerge from drought, one or two big storms can also do the trick.

"The heavy rain will run off, and a lot from [Tuesday's] storm just ran off into the bay," Paschetag said. "But tropical storms are one way to get what you need."

Staff writer Daniel LeDuc and staff researcher Bobbye Pratt contributed to this report.

Hurricane History

Dennis is churning its way across the Atlantic, bringing with it much-needed rain. Whether it will hit land is yet unknown. The region has felt the effects of hurricanes in the past. Some of the worst cases during this century:

1906: 350

1938: 680

1944: 46*

Carol (1954): 60

Diane (1954): 184

Hazel (1954): 347

Connie (1955): 43

Ione (1955): 166

Donna (1960): 148

Donna (1960)**

Agnes (1972): 122

David (1979): 1,100

Hugo (1989): 504

Fran (1996): 28

* Number killed

** Second landfall

SOURCES: National Hurricane Center, NOAA

CAPTION: A firefighter rescues Sara Ceron from her car on the flooded FDR Drive in New York City, where torrential rains swamped roads and subways yesterday.