By the time summer finally takes hold, sun-starved Cape Anners and others across the North Shore still may not want to step outside.

The reason: mosquitoes.

"The mosquitoes will be worse than people have seen in years," said Walter Montgomery, director of the Northeast Massachusetts Mosquito Control and Wetlands Management District, which includes Manchester and Essex. "As soon as the (rainy) cycle breaks and we have a few days of warm weather, the numbers are going to be astronomical."

After weeks of unrelenting rain, the equivalent of four years' worth of mosquito eggs will be hatching, Montgomery said.

"My guess is, and this is speculation," he said, "but probably by Tuesday or Wednesday ..., the population will start to explode."

Montgomery explained that female mosquitoes — of the Aedes vexan variety — lay eggs in the muddy areas around wetlands. Those eggs can lie dormant for years, especially in dry seasons. The past few summers have been drought seasons, keeping populations of the blood-sucking bugs to a minimum.

But the recent wet and rainy weather will force dormant eggs to hatch, he said. This year, the ground is saturated and can't absorb any more water. Without any sun to dry out the ground, the eggs mature.

"All the wetlands are full, and they'll stay full," he said. "It will absolutely produce tons of mosquitoes."

His agency collects the bugs twice weekly, and up until a few weeks ago the 32 cities and towns in the district had enjoyed particularly low numbers of the bugs because of a dry spring and cool temperatures.

All that changed with the wet and dreary June.

"Who could have known it would rain for a month?" Montgomery said.

He said people should take the standard precautions when outdoors: wear long sleeves when possible, and use a mosquito repellent with the highest concentration of DEET you can find.

"You know what's going to make it real bad is people will really look forward to getting out," he said. "They'll be covered with mosquitoes and won't be happy about it."

Nevertheless, be most diligent during the early morning and early evening hours, this species' preferred feasting time, he said. "They won't bother in the middle of the day unless you're in woods."

Montgomery said people don't need to worry, yet, about mosquito-borne illnesses like West Nile virus or Eastern equine encephalitis. The species that carry West Nile virus flourish in drought conditions because their habitat is rank water, he said.

"Right now, all the water is fresh and will continue being refreshed."

Mosquitoes carrying Eastern equine encephalitis don't appear until later in the summer, from mid-August through mid-September.

"It's too early to predict what might happen with that," he said.

Montgomery said residents in his districts' 32 communities — which include Manchester and Essex — can call his office, and he can send a truck to spray areas hard hit by mosquito populations.