Cicada Emergence Formula
This information was posted in a comment, but it’s important enough to place on the homepage in a post:
Gene Kritsky was nice enough to send a paper he wrote with a formula for predicting the emergence date. E = (19.465 - t)/0.5136, where E = emergence start date in May and t = average April temperatures in °Celsius. His formula worked like a charm for predicting the Brood X emergence in Cincinnati. 80% of his sites had begun the emergence on the predicted date of May 14th of that year. Also when the ground temperature reaches a consistent 64° Fahrenheit that is another good sign the emergence is about to begin.
Try it out:
Updated: we updated the form to accept 3 numbers past the decimal in case you have super-precise temperature information.
To find the Average Mean Temperature in Celsius on the Weather Underground site:
- Go to the site
- Enter your zip code in the box labeled “Find the Weather for any City, State or ZIP Code, or Airport Code or Country”
- Find the section of the page labeled “History & Almanac”, and click the “April Calendar View” link.
- Then scroll to the top of that page and you’ll find the info you need.
Thanks to Roy Troutman and Gene.
Will the cicadas emerge in the Wisc. Northwoods? Like the Hayward and Minocqua areas?
Comment by Kathy — March 19, 2007 @ 12:06 pm
I looks as though only the far southern end of Wisconsin will see any Brood XIII so you are in the clear up north.
Comment by Roy Troutman — April 9, 2007 @ 10:21 am
Hello Ray:
Great site.
My husband grew up in the Chicago area (St. Charles, IL), and wants to go visit his family this year at the cicada time.
I looked at the Weather Underground site, and did not find an ‘average mean temperature’ map. Lots of current temps, but not an average.
Can you tell me your best current estimate of the emergence of Brood XIII in the Chicago area?
Thanks a bunch!
Best regards.
Comment by Sharon — April 10, 2007 @ 3:06 pm
Oi Veh — looks like May 30th at this point.
Comment by Dan — April 11, 2007 @ 3:29 pm
I must be missing something: I just tried this for Chicago and got an answer of 379!! If I’m reading
the formula correctly, it is E = (19.4652 t)/0.5136
For Chicago it would become E = (19.4652)(10)/0.5136 = 194.652/0.5136 = 378.995
I see a space between the 5 and the 2 as given
above; did I misinterpret the formula?
Thanks, Bob
Comment by Bob Jacobson — April 11, 2007 @ 6:22 pm
It’s (19.4652 minus the temperature) divided by 0.5136
Comment by Dan — April 11, 2007 @ 8:36 pm
Hey Sharon & all,
Here is the best way to get to the average mean temps for April (so far):
go to http://www.wunderground.com, type your zip in field at top, click on magnifying glass.
when on page for your city scroll down to “History & Almanac” box & click on “April Calendar View”.
when on calendar view page scroll up to “Monthly Summary” & find the mean temperature on the 2nd line
in middle under “Avg:”. It will be listed in ºF/ºC. use ºC.
Hope this helps,
Roy
Comment by Roy T. — April 12, 2007 @ 10:44 am
Based on mean temperature, the predicted emergence in our area (Batavia, IL) is June 1, 2007. How long will they last? When is it safe to have an outdoor party with kids, sprinklers, splash pools etc?
Comment by Valerie — April 14, 2007 @ 9:13 am
Hello Valerie,
I would expect about 4 solid weeks of action out of the cicadas after the last week of May. It is actually safe to have the party at any time the while cicadas are out & they may just drown out the kids laughing & screaming during their party.
Hope this helps,
Roy
Comment by Roy T. — April 19, 2007 @ 10:30 am
It will be interesting to see if this holds generally for Illinois localities. In 1956, at Raccoon Grove, IL (35 miles SW of Chicago), Dybas and Davis measured the highest emergence density of periodical cicadas ever recorded. (This site has since been hit by Dutch Elm disease.) They had emergence traps out everywhere and the first nymphs began emerging on 4 June. The weather data for the nearest locality suggests a date closer to 22 May by Gene’s formula. Year to year temperature variation will add to the uncertainty too.
Overall, cicadas will come out earlier in sunny spots and on south-facing slopes, and later in deep woods and gullies. I’m also guessing things will be earlier in the warm urbanized areas of Chicago (in past emergences cicadas were coming out of the ground in suburban yards around 24-25 May.)
Since the emergence is usually strung out over one to two weeks, and since individual cicadas live for 2-3 weeks roughly, you can count on 3-4 weeks or so of noise once things get going.
Comment by David Marshall — April 29, 2007 @ 2:32 pm
I was wondering what kind of soil or dirt they live in for 17 years. I currently work on a project
and years ago it was a soy bean field. Do you think there are cicadas in this type of dirt/soil?
Thanks!
Melissa
Comment by Melissa — May 2, 2007 @ 10:11 am
Hello Melissa,
I would think if the field has been re-wooded for 30 or so years that the periodical cicadas could have re-established themselves. My grandfather owned about 270 acres of cornfields & re-planted trees on almost all of it back in the late 40’s, 50’s, & 60’s. The periodicals have “moved back in” to the whole 270 acres pretty much.
Thx,
Roy
Comment by Roy T. — May 2, 2007 @ 1:17 pm
The great move to the surface has begun. I’ve seen already several dozen little mud turrets popping up around my back yard.
When you remove this turret covering you see a neat little round hole that looks like it fits a cicada nymph perfectly.
It won’t be long now…
Comment by Pete — May 4, 2007 @ 7:50 am
Tonight CBS 2 news at 10:00PM predicted the Chicago area will see the brood XIII cicada emergence beginning May 22nd. As a former left coaster, I’m completely unprepared for this event!!
Comment by Kay — May 4, 2007 @ 9:20 pm
Cicadas are out - here in Bull Valley, Illinois. They’re all over our back yard - resting under old logs and other stuff. They have burrowed up through large holes.
There are a lot of them!
Comment by Mary — May 7, 2007 @ 8:10 pm
the cicadas are in lake geneva, watched the emergence tonight. very cool
Comment by carol — May 26, 2007 @ 8:12 pm
anynoe seen any in the romeoville area?
Comment by Deborah — May 29, 2007 @ 4:53 am
Cicadas first sighted in my backyard in LaGrange Park, IL. on May 19th, 2007.
As of this weekend, we can’t walk in the yard without stepping on one.
They are facinating and because they don’t bite or sting, my 3-year-old
likes to play with them and feel them crawl on his toes.
Comment by Amanda — May 29, 2007 @ 9:41 am
My wife is pretty sure she seen a female coming out in our garden yesterday! We live in East Troy, WI. Could this be one?
Comment by Jon — May 29, 2007 @ 9:12 pm
I live in Rochester Indiana and we have not seen any, will we be getting them?
Comment by CHERRIE — May 30, 2007 @ 11:21 am
My son had the pleasure of sighting the cicadas in our own backyard on May 29th. We live in New Lenox, IL. He is in all his glory, not believing that we would see any Cicadas…
Comment by Shirley — May 31, 2007 @ 6:47 am
It is not 5/31 and we have yet to see a single cicada in our subdivision in Batavia, Illinois.
Does this mean that we will not get them? Is there a specific date that we will know that we are
“safe” from a cicada emergence?
I am a cicada-phobe.
Comment by Valerie — May 31, 2007 @ 11:04 am
I was in Iowa this last week staying with a friend near Iowa City, and a cicada landed near his garage, so we put it in a jar and killed it with a cotton ball full of alcohol so it could be preserved.
I live in Minneapolis, MN, and was wondering if there will be an emergence near me that I can go to and photograph.
I have loved cicadas–and other insects–since I was a little boy growing up in Cedar Rapids, IA. I used to climb up trees in the late summer and wait for the annual cicadas to climb down in the late evenings. Many times I caught them with my bare hands by moving very slowly and grasping them over the front of their wings where they hinge with my thumb and forefinger. Of course, the minute I did this they started making lots of noise and tried to flap their wings. So I would have this screaming, pulsating bug in my hand and would run inside with it and let it go in the house. My mom thought it was interesting, to say the least…
Tim
Comment by Tim — June 1, 2007 @ 8:08 am
i garden for several lake geneva estates and there are thousands of these fabulous creatures concentrated in one part of a yard and then none to be seen in the next. same with the town - they’re all over in the streets, on houses, shrubbery, etc in one block and then none on the next. their distant sound is like an eerie sci-fi alien invasion. very cool.
haven’t seen them south of lake geneva - yet.
love it!
Comment by shelly — June 3, 2007 @ 10:54 pm
I followed all the emergences around Chicago and on May 22 only about 5 sites reported very small numbers of cicadas. The first major wave appeared on Memorial day and emerged all day long. The biggest wave ( May 31) was 3 days later. I have heard reports that a few a still emerging all around Northern Illinois.
Comment by Bill Cicada — June 4, 2007 @ 8:03 pm
We didn’t go from nothing to overwhelming as fast this year as I seem to recall 17 years ago —
but we are in full swing this morning!! Highland Park, north and east —
Comment by Janet Tabin — June 7, 2007 @ 5:16 am
i’m going crazy and can’t wait til these guys are gone. i’m in riverside and, slowly but surely, they have gotten worse & worse, but not quite as bad as glencoe seemed 17 & 34 years ago. it is very loud here, but the noise doesn’t bother me in the least… it’s the darn things flying and lurking around - it’s going to be a long june!
Comment by Margaret — June 8, 2007 @ 12:20 pm
Cicada Mania in Valparaiso Indiana!!!! Yuck! I opened our sliding glass door Saturday and heard a weired buzzing sound. My fiance said it was probably an electrical problem down the road. We live in the country, extremely quet and peaceful. I went for a walk this morning and the closer I got to the woods, the louder the sound was. Then I began to see SEVERAL random red/orange wings laying around and then I just knew, we’ve been taken over. I walked a little further and one was in the road. I was getting ready to step on it when it suddenly flew up into a tree. YIKES!! I ran home. When will they leave??
Comment by Amy — June 13, 2007 @ 2:53 pm
I was just curious if Central to Eastern KY will see cicadas emerge this year?
Comment by JC — June 14, 2007 @ 2:51 pm
Kentucky… no major emergence this year — but next year, brood XIV. You might see a straggler or two this year.
Comment by Dan — June 14, 2007 @ 3:37 pm
We live about 6 miles northwest of Janesville, WI, about a block and a half from the Rock River and seem to be one of the few spots in the area that experiences the cicada invasion; we heard the first buzzing on May 27th. I remember hearing about these guys as a teen at the Chicago Museum of S&I but never imagined I’d be living amongst them someday. We lived here for 2 years when we were suprised by the weird buzzing and all that goes with it. Little did we know that the trees we had just planted would be prime targets. We ended up loosing about four trees but thankfully got a 17 year jump on them this time. Our yorkie snaps them up like candy!
Comment by Ron — June 14, 2007 @ 7:30 pm
Anybody know if we’ll see any in Carol Stream, IL 60188? None this year so far, but we saw a couple last summer.
Comment by Greg — June 15, 2007 @ 6:18 pm
I haven’t seen any in Antioch, nor have my friends in Gurnee, Lindenhurst and Lake Villa. Does that mean we will not see any or at least not very many?
Comment by Laurie — June 16, 2007 @ 10:37 am
i saw some in gurnee when i went to six flags. not many..but some. They are all over by house house in Schiller Park. You’ll be stopped at a red light, and they’ll be swarming EVERYWHERE! It’s quite gross. You can pump gas during the day without at least 10 of them landing on you..and you see them all crawling all over EVERYTHING. gross x38473.
Comment by Lauren — June 16, 2007 @ 11:10 am
I am curious as to the ratio of males to females. I went to some woods nearby and came back with
about 150 cicadas because I want them to be back in the area. Do you think my effort might be
sucessful?
Comment by Jim — June 17, 2007 @ 5:16 am
The ratio should be 50/50.
Comment by Dan — June 17, 2007 @ 3:29 pm
I live in Royal Oak, MI, will the cicadas be emerging out here?
Comment by Jason — June 19, 2007 @ 10:52 am
When should the Ohio Valley region of West Virginia see an emergence of cicadas again? Huntington, WV area
Comment by Audra — June 21, 2007 @ 10:17 pm
I had posted question on June 15 asking anybody if they knew if we’d see them in Carol Stream, IL 60188. Well were seeing them now! Only since last week of July. Is this unusual? Did anybody else get the substantially later than May/June when other areas saw them?
Comment by Greg — August 5, 2007 @ 5:55 pm
The Caicada’s are out in southern New Hampshire. The emergence started about a week ago.
Comment by Terry Newport — August 7, 2007 @ 12:24 pm
Cicada’s hatching in Knoxville, Tennessee. I’m watching one in my dining room right now. It emerged from the ground about 2 hours ago,
has been very still for about an hour.
This is new for me. Jerry - August 12 @ 9:15 PM
Comment by Jerry Glenn — August 12, 2007 @ 6:16 pm
http://www.ncdc.noaa.gov/oa/climate/online/ccd/meantemp.html
There is a LARGE list of cities and states mean temperatures found here.
Not eaten a cicada yet, but our chickens will love them.
Comment by Bruce Westfall — September 15, 2007 @ 10:53 am
Hey - great site. We are planning our wedding for June 7th, outdoors of course, or I wouldn’t be worrying. What kind of invasion do Cicadas have over downtown urban areas? Example: Downtown Cincinnati?
Comment by Amanda — February 26, 2008 @ 6:55 pm
[…] will emerge once the temperature is right, typically at dusk. The best method we know of is using Gene Kritsky’s emergence formula. This is a tool that will allow you to determine the approximate time when the cicadas will emerge […]
Pingback by Cicada Mania » Brood XIV: When, Where and What do they look like? — April 1, 2008 @ 6:39 pm
[…] year Gene’s emergence formula calculator (try it!) did a good job of predicting the Brood XIII emergence, and the 2008 temperature study […]
Pingback by Cicada Mania » 2008 Cicada Temperature Study — April 12, 2008 @ 7:21 am
I found tons of holes this weekend (April 26-27) at my cabin in Union County PA (base of Jack’s Mountain near Millmont, PA) and one just left its hole. A hundred in just one square yard area and hundreds more holes around the area…going to be a loud summer!
Comment by Vaughn Murray — April 27, 2008 @ 7:41 pm
[…] Gene Kritsky’s formula, and the Weather Underground, I’ve pulled together some sample emergence predictions. Chances […]
Pingback by Cicada Mania » Emergence Predictions — April 30, 2008 @ 5:46 pm
cecidas ar3 so s3xy
Comment by mireek — May 5, 2008 @ 7:03 am
I was told to use tobacco cotton to protect my 1 1/2 yr. old crabapple trees. The cotton seems heavy for the trees to bear, and I don’t want to lose them. It is very windy here. Tree nets are very hard to find.
Comment by mary whalen — May 9, 2008 @ 3:44 pm
i live in shelby county kentucky i just wanted to tell u all i have thousands of cicadas in my yard already they are everywhere
Comment by chris — May 29, 2008 @ 6:39 pm
Mass emergence of cicada began yesterday (31 May 2008) here in Bellefonte, PA (Central PA, zip code 16823). I like to work outside with a wireless laptop and a wireless phone. Looks like I’m going to have a lot of background noise!
Comment by Jeff Johnson — June 1, 2008 @ 4:59 am
i live in between lake city and clinton, tennessee and for about 3 weeks now they have been emerging. i live about 2 miles from norris lake and about the same from I-75 north. there are so many that you can actually here them over the noise of the busy interstate. also what is the real deal with the folklore about the “w” or “p” on the wing tips i heard that these markings were “w” for wartime and “p” for peace time is this true? thanks
Comment by mike — June 2, 2008 @ 7:33 am