There's been a groundswell of 17-year cicadas in Virginia and other southern states, as revealed by a fresh wave of photos and eyewitness reports. In some areas, the outbreak has been accompanied by the insects' loud chorus call. And that's music to the ears of University of Connecticut entomologist John Cooley.

"That's where I'm heading," Cooley told NBC News. The weather is still too cool in New England and the New York City area for a full-blown Brood II emergence, so Cooley is planning a field trip to watch the insects rise up in Virginia.

This is the big year for Brood II cicadas, which are expected to emerge from the ground in the billions over an area of the East Coast ranging from North Carolina up to Connecticut. The bugs are hard-wired to spend 17 years underground, feeding on the fluid from plant roots, and then pop up during the appointed spring when the soil temperature reaches 64 degrees Fahrenheit (18 degrees Celsius).

For weeks, bug-watchers have been posting their sightings (and soil temperature readings) to websites such as Cooley's Magicicada.org and RadioLab's Cicada Tracker. Another website maintained by the Sutron weather information network tracks the soil temperature in Washington, D.C. 

When the winged cicadas throng, they can cover trees and buildings — and raise a din as loud as a lawnmower or jet engine (90 decibels). Over the course of four to six weeks in May and June, the bugs mate, lay their eggs and die, setting the 17-year life cycle in motion once again. (Scientists theorize that there are evolutionary advantages to the long, odd-numbered cycle.)

Although the cicadas have been patiently waiting for 17 years, some cicada-watchers up north are getting impatient with the pace of the emergence. Cooley said the relatively slow pace may be due to this spring's cool temperatures. In order to bring the soil up to 64 degrees F, air temperatures have to get significantly higher than that on a consistent basis.

"I want 80s and 90s," he said, "and so do the cicadas."

Dave Ellis / The Free Lance-Star via AP

Brood II cicadas emerge in the Leavells Crossing neighborhood in Spotsylvania, Va., on May 16.

Carol via Twitter.com/oikwtm_

Cicadas throng near a house in Fredericksburg, Va.

Carol via Twitter.com/oikwtm_

A cat looks through a screen door as cicadas swarm outside a house in Fredericksburg, Va.

Slideshow: Return of the cicada

Take a closer look at the curious 17-year life of the flying bug as the East Coast prepares for an invasion.

Launch slideshow

More about the cicada outbreak:

• Cicadas crawling out of the ground in droves
• 'Swarmageddon' comes to North Carolina
• Bug-watchers see cicadas on the rise
• Cicada emergence sparks early buzz

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with NBCNews.com's stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

Ariel Schalit / AP

Locusts land on a sand dune in Negev Desert, southern Israel, near the border with Egypt, March 5. A swarm of locusts crossed into Israel from neighboring Egypt Monday, raising fears that Israel could be hit with a biblical plague ahead of the Passover holiday. Israel sent out planes to spray pesticides over agricultural fields to prevent damage by the small swarm of about 2,000 locusts, said Dafna Yurista, a spokeswoman for the Agriculture Ministry. The ministry also set up an emergency hotline and asked Israelis to be vigilant in reporting locust sightings.

Scientists can learn a lot about the locusts swarming over Egypt and Israel just by looking at the pictures. Keith Cressman, senior locust forecasting officer for the U.N. Food and Agriculture Organization, is based hundreds of miles away in Rome — but he can tell that these particular bugs may be on their last legs.

"The few good pics I have seen of the locusts show that they are a brick red rather than pinkish," Cressman told NBC News in an email. "Both colors indicate they are immature adults, but the dark color suggests they are old and tired rather than young and hungry. Hence, the infestations arriving in northeast Egypt and Israel will probably come to nothing." That's the good news. The bad news is that other locust swarms could pose a more serious threat to the region's agriculture later this year. To get the details, check out the full story in Cosmic Log.

Ibraheem Abu Mustafa / Reuters

A Palestinian farmer displays locusts at a farm in Khan Younis in the southern Gaza Strip, March 5. Palestinian officials said locusts had not hit Gaza in several decades and numbers of locusts that reached Gaza on Tuesday were small but the Agriculture Ministry said they have taken all necessary steps to fight it if larger numbers hit the Gaza Strip.

Amir Cohen / Reuters

A swarm of locusts fly near Kmehin in Israel's Negev desert.

Ariel Schalit / AP

A locust on a sand dune in Negev Desert, southern Israel.

More about locusts:

• Locusts hit Egypt and Israel before Passover
• Gaddafi's fall leads to desert locusts' rise
• Locusts illustrate the science of swarming

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.