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When Will The Fireflies Light Up Your Back Yard?

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When Will The Fireflies Light Up Your Back Yard?

Catching fireflies (or “lightning bugs”) is a pastime we all look forward to every summer. But how soon should you get your Mason jars (and the palm of your hands) ready? Weather could give you a clue.

Yes, fireflies, which are actually a type of beetle, share a relationship with weather that goes deeper than the summer solstice. Their larvae live underground during winter, mature during spring, and then emerge in early summer anywhere from the third week in May to the third week in June. What dates you’ll begin to see fireflies in your back yard is somewhat of a mystery, and changes from year to year. But scientists do know that air temperature and rainfall have something to do with it.

Muggy Bugs

Unlike people, fireflies love warm, humid weather. It helps them to survive. So in years when summer-like weather arrives before June does, fireflies tend to appear in lawns, gardens, and trees earlier than usual — sometimes as early as late spring. All the warmth from early summers and mild winters fools lightning bugs into thinking it’s later in the season than it really is, and so they emerge sooner. Mild winters also mean a larger lightning bug population in your back yard, since the young will have had an easier time surviving the cold.

Wet springs also lead to earlier firefly flash displays — likely because firefly larvae feed on snails, slugs, and pill bugs which are brought out by rains. The more damp the soil is, the more plentiful these creepy-crawlers will be, and the more food young fireflies will have to carry them into adulthood. And it’s the adult fireflies that flicker (mostly as a way to attract mates)!

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As much as damp weather provides an ideal environment for fireflies, dry conditions provide the worst. Droughts and heatwaves stress firefly eggs and larvae, causing them to die off before they’ve had a chance to emerge. The dates when lightning bugs appear will also be delayed due to the heat stress.

Expect the Brightest Fireflies on the Warmest Nights

Weather not only plays a role in how soon you’ll see lightning bug flashes, but how many flashes too. On warm and humid evenings, lightning bugs can light up a field as if it were a Christmas tree! But on cooler nights when air temperatures take a dip into the 50s, don’t be surprised if you wait a minute or longer to see a single flash. Why is this? Fireflies, like most insects, are cold-blooded (meaning they depend on heat from their surrounding environment to help them function), so their activity peaks when temperatures rise, and slows when temperatures drop.

Or maybe you are planning to trek to the Great Smoky Mountains to view this year’s synchronous firefly display (it’s the largest population of synchronous fireflies in the Western Hemisphere, and begins May 30th ) Take a look at the video of this incredible event:

Have you seen fireflies yet in your backyard? Leave us a comment and “enlighten” us!

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1 Rita { 02.05.19 at 9:08 am }

@ Michael from Australia. There are fireflies on the far North Coast of NSW. I have seen them this evening in my yard at Wollongbar and at a friend’s property near Wardell. As a young child I recall large amounts near Nambucca Heads.

2 Deston { 10.30.18 at 9:17 pm }

It’s October 30th and my yard is full in Central Missouri!

3 Susan Higgins { 10.12.18 at 8:40 am }

Hi Michael, we don’t have any information on that, our apologies. Most of the information we cover is for North America. We’ve located this article online that might be helpful to you:

4 Michael { 10.09.18 at 9:53 pm }

Hi I’m a Aussie can anyone shed light on fireflies in Australia and when we should see them ? Cheers everyone

5 Francis Nuzzi { 10.08.18 at 12:07 pm }

I am in northern delaware. I have been tracking for years just how late I can see fireflies. I still saw a few last night – October 7, 2018. The temperature was 72 F. This is the latest I have seen them. Before this year the latest I saw them was October 2. I will keep tracking.

6 Crystal { 10.04.18 at 2:55 pm }

STILL seeing fireflies in October in South Central PA…I have never seen them so late in the year!!! Crazy weather

7 Kelly Griffin { 10.02.18 at 8:38 pm }

Fireflies all over my backyard here in Dallas…it’s wonderful…💫

8 Anne N. Dean { 09.30.18 at 9:33 pm }

9/30/18 We came home from eating out at 9:15 pm. We started seeing sparkle in the gravel driveway and then in the flowerbeds and then the yard. It was like Christmas. We have never ever seen so many lightning bugs this late in the season. They all stayed on the ground and were all around the house.
Madison County VA

9 Gary Cunnane { 09.19.18 at 7:19 am }

I live near the coast of NJ in an area that has many red cedar trees. We had dozens of lightning bugs in the yard on 9-17 this year. I have never seen that in my 60 plus years of lightning bug observation. They also emerged earlier this year in mid-June

10 abeza { 09.15.18 at 8:07 pm }

This evening, at Merrick New York on Sept 15, 2018 at 7:40PM, I have seen a couple of fireflies flashing. I was surprise seeing this happen in the middle of Sept.

11 Susan Higgins { 09.14.18 at 8:38 am }

Hi Lrose, that’s interesting! We haven’t heard about them this late in the season. But with Mother Nature, anything is possible, as we all know! Thanks for your comment.

12 L rose { 09.13.18 at 7:51 pm }

I’ve seen lightning bugs/ fireflies the past two weeks here in staten island ny
Today is September 13th 2018

13 Judith { 09.08.18 at 2:39 pm }

We saw fireflies in our front yard in Bryn Mawr PA the past two nights! On September 6 and 7, 2018. I don’t ever remember seeing fireflies that late in the season. And based on their flashing patterns, there were several different species active as well.

14 Alison Benton { 08.16.18 at 8:52 pm }

Here in Hampton Va we were blessed to have 2 separate Firefly seasons. They were abundant in mid June and then it was over. To my surprise tonight they’re back. Bigger and brighter than I’ve ever seen. This will be my first time ever seeing them this late in the Summer. What a treat.

15 Carrie { 07.01.18 at 9:28 pm }

The last 2 nights have seen them in Westport Massachusetts.. haven’t seen them in a couple of years . I’ve been enjoying watching them

16 Ken Stone { 06.17.18 at 10:28 am }

Just moved to Huntsville, Al from California; family was thrilled to see our backyard filled with fireflies. Trying to find info on when the ‘season’ ends.

17 Kate { 06.14.18 at 6:24 pm }

Not seeing any yet in Florissant Mo. Been looking for them since June 1. Crazy weather here lately could be the cause. Hope to see them soon

18 jujones { 06.12.18 at 10:15 pm }

I live in Hanover, PA, and usually see them before now (6/12/18), but so far, none. We’ve had lots of rain, but not that much heat. Hope they’re just late and not dying out – they are so, so beautiful…

19 Kim { 06.04.18 at 1:26 am }

I’ve lived in California all my life. My mom had always wanted to take me back to see fireflies. Well, next week I will be in Indiana. I’m hoping like crazy I get to see fireflies!

20 Samuel Jones { 06.03.18 at 9:42 pm }

The flreflies are are really putting on a show here in Stone Mountain, GA tonight. It is about 9:30 PM, they are really beautiful. We have had a lot of rain and it is hot and muggy. I guess explains all of the activity.

21 PghPatti { 06.03.18 at 9:39 pm }

First fireflies this yearJune3, 2018, in Upper St. Clair, PA

22 Jim { 05.30.18 at 11:18 pm }

Fireflies in N WI end of May warm and humid

23 Ronald Friesz { 05.30.18 at 10:33 am }

Keytesville Missouri
May 30

24 Shannon Marissa { 05.27.18 at 9:14 pm }

Just moved from California to Alabama City and for the past week or so I have seen them. Only above the lawn mind you. As with one other person, I thought I was seeing things at first but I grabbed my phone to video the sight to assure myself I wasn’t.
My only question left unanswered is the fact that everything I have read so far indicates a different color ‘light’. I am only seeing bright white flashes where most seem to be yellow?

25 Roxanne DuBris { 05.27.18 at 7:22 am }

First sighting last night – May 27, 2018 – in rural Delaware, Ohio, earlier than I remember from other years. We had a colder-than-usual winter with scant snow cover, followed by a very rainy spring. Recent temperatures above normal for late May.

26 Dave { 05.26.18 at 11:03 pm }

First flashes of the year – Timonium, MD.

27 Kim Whitmire { 05.20.18 at 10:03 am }

We moved to three mountains of Western North Carolin from Austin, Texas, in February. In Austin, fireflies would come out in the early evening on warm spring nights. Here, I walk my dog around 11pm and have never seen them. I was wondering if we even have them here…until 2:30am today when I woke up. Something made me look out the window and I was greeted with a magical scene of hundreds of fairly large flashing lights all over our property down the mountain. I was stunned & immediatewoke up my husband to come see. I wasn’t sure if I was dreaming! It was truly a stunning scene.

28 Scott { 05.17.18 at 8:37 pm }

Fireflies in Cleveland, Ohio!

29 Scott { 05.17.18 at 8:37 pm }

Lightning bugs in Cleveland, Ohio!

30 Laura Tummins { 05.15.18 at 11:12 pm }

We have had lightning bugs for the last couple of nights here in McEwen, TN. This is earlier than last year. May 15, 2018.

31 Cathleen { 05.15.18 at 10:34 pm }

Fireflies were out tonight in Arlington, Texas!

32 Susan Higgins { 05.14.18 at 11:48 am }

Excellent! Thanks for sharing, Marie!

33 Marie { 05.14.18 at 8:16 am }

Our family are new Texans from California and have never seen fireflies before. Last night while enjoying Mother’s Day evening outside we saw about a dozen fireflies give us our first light show. We were all transformed into 10 year children as we watched them dance through the yard. About 2 weeks ago we thought we saw a flash out at the back of our property but it didn’t continue so we thought our eyes were playing tricks on us but tonight we realized our suspicions were true. We live an hour north of Austin in the outskirts of eastern Temple, Texas on 2 acres with a miles of cornfields behind us. This was yet one more more thing that has made Texas the most wonderful place in he U.S. to live!

34 Alissa { 04.30.18 at 10:48 pm }

Let one land on your hand for a little while, then let it fly away. No harm in that. I grew up in firefly country and it’s what I miss most being away. Hope my kids can see them some day.

35 Chris Wisman { 04.30.18 at 12:00 pm }

I live in Ocala Florida and I saw 2 last night in my backyard 4/29/18. This is as far south I have seen them.

36 Leslie { 04.12.18 at 9:26 pm }

April 12, 2018. Fireflies in Knoxville TN. This is earlier than I can ever remember seeing them and we have had a very wet spring. Very strange, beautiful, but strange.

37 Mark Sweezy { 04.06.18 at 9:48 pm }

Just came across this web page and it answered my question.
It’s April 6 2018 and I’m seeing fireflies here on the small river where I live in upstate S.C.

38 Elaine Mitchell { 04.04.18 at 4:21 pm }

Fireflies last night 4/3/18 in Athens, Georgia. Tons of them high in the trees. Just beautiful!

39 Karen { 04.03.18 at 10:38 pm }

Fireflies in FairPlay ,SC. 04/03/2018. I love it. One day before my b-day.Great present !!!

40 Ashley w { 04.03.18 at 8:46 pm }

4.3.18-I live in eastern North Carolina and my back yard is full of lightening bugs tonight!!

41 Tim Boatfield { 03.31.18 at 9:12 pm }

We have fireflies in lindale, ga tonight.

42 Angie { 03.28.18 at 8:28 am }

I live 20 miles South of Birmingham, Alabama. During my evening walk last night, I saw many fireflies, in a wooded area, flashing high up in the trees. I really had to watch for a while to figure out what I was seeing. At this time of the year, seeing them was so unexpected. Very interesting that they weren’t close to the ground, as fireflies do during the summer. Curious.

43 Catherine Oenbrink { 03.25.18 at 1:53 am }

I thought I was seeing things! Woke up at 2 am and saw these extremely bright flashes in the back yard. Millen, Georgia

44 M Washington { 03.24.18 at 8:55 pm }

It is a mild evening in Georgia- 70 degrees and 8:30 and… we have fireflies! Seems early to us and they are much higher up in the trees with more of a random ‘ flash’ than usual.

45 Janice { 03.19.18 at 8:12 pm }

Just saw lightning bugs in Loris, SC tonight! Thought it seemed weird, hence I found this article.

46 Susan Higgins { 03.12.18 at 8:32 am }

Wow!Thanks for reporting in, Kathleen!

47 Kathleen Adkins { 03.12.18 at 12:18 am }

Fireflies in Porter, Texas two nights now.

48 Bryan Harrell { 03.10.18 at 8:11 pm }

Checking in from Wilmington NC 3/10/18. Fireflies tonight 8pm. By Cape Fear river. Seems a little early to me. 58 degrees.

49 Shannon { 11.27.17 at 9:51 am }

Seen an amazing firefly flash show on Nov 26 in Cold Ottawa winter in Canada! My backyeard trees were lit like a xmas tree from thousands of fireflies!! It look absolutely amazing and magical.
I didn’t think they can still be around in this time of the year. and I highly think they are attracted by neighbour’s mosquito trap light or buzz.

50 angel { 11.14.17 at 11:39 am }


51 Kimi Rowell { 10.30.17 at 6:46 pm }

I’m curious as to why I’m still seeing random fireflies here in San Antonio, Tx and its October 30, 2017. If anyone knows I’d love to find out!

52 sherry Gunn { 08.30.17 at 9:19 pm }

We have been seeing fireflies since May and all the way through to today, August 30, 2017. This has been the longest season for fireflies I’ve ever seen. Love the lightning bugs. Parker County, Texas

53 Virgie { 08.27.17 at 12:17 pm }

Denver, CO 9am bug crawling across the floor. I let it crawl on a paper to take it outside. It was a black beetle and it lit up red underneath. Not sure what it was. I’ve heard that there is no lighting bugs in Colorado. This is not the first time I have seen one of these bugs.

54 Susan Higgins { 08.10.17 at 8:51 am }

Bill Bean, interestingly, the spring rains would have kept them on schedule for summer; they may have had a second wave of hatching. It’s been dry here in Maine and we haven’t seen many at all.

55 Bill Bean { 08.10.17 at 1:09 am }

Saw Fireflies tonight (Wed., Aug. 9, 2017). Isn’t this rather late? Yes, this is Ontario, but in this area, June is the norm. We had some major rains in the late spring and early summer. Might the rain have delayed their cycle?

56 Jennifer Maggio { 07.04.17 at 11:53 am }

The lightening bug magic show here in our Southern New Jersey backyard is stunning this year! Last evening, July 3rd, from dusk until past dark, the whole woodsy area…and yard… and neighborhood …was sparkling nonstop with bright twinkling lights! Like 4th of July sparklers set free without sticks! We were enchanted beyond words.

57 Jack Gleaton { 06.29.17 at 11:04 pm }


For the first time this year this 73 year old white man just saw one(1) Firefly(Lightning Bug is the name used by the local people here in Southwest GEORGIA, USA about 70 miles North of the GEORGIA – FLORIDA state line) in his front yard under one of the three(3) River Birch trees about 8:45 PM. Later, about 8:55 PM in the backyard I saw two(two) more Lightning Bugs under an Old Wolf Pine tree.
It had been raining with a lot of lightning and thunder for about the past six(6) to seven(7) hours and prior to the rain it was very hot and humid. At the time of the sighting the temperature was about 72 – 73 degrees and 6(six) to 7(seven) miles per hour wind with heavy overcast sky.
I think my first time of remembering seeing a Lightning Bug was about one month after my fourth birthday on the 2nd of May.

58 Heather { 06.28.17 at 10:47 pm }

Beverly, MA…the last time I saw fireflies here was about 9 years ago. I always look for them but they seem to be disappearing from this area. Growing up in CT I would see tons every single year, but we lived in a damp region. Where I am now is surprisingly dry considering it’s a coastal town.

59 Diane Alden { 06.25.17 at 9:44 pm }

So far have only seen one firefly this year, today June 25, 2017. Tonight. Hoping for more. Hoping………………..

60 Dara Wegman-Geedey { 06.03.17 at 11:21 pm }

Saw our first 2 fireflies tonight 6/2/17 around 8:45 pm — one in our backyard, one in the front yard. Rock Island, IL

61 Darcy { 05.28.17 at 10:43 pm }

First firefly tonight outside of Rochester NY!

62 gandalf80 { 05.28.17 at 1:31 pm }

PLEASE do not encourage “catching” fireflies (or lightning bugs, as they’re called in east Tennessee)because they are endangered primarily by light pollution, but also habitat encroachment and insecticides. We can look with our eyes, not our hands.

63 Michelle { 05.26.17 at 12:34 am }

First night of fireflies here in Northern Alabama tonight, May 25th.

64 Tammy { 05.24.17 at 8:24 pm }

Yes lighting bugs may 15th beaverdam ky.

65 Valerie { 05.24.17 at 6:50 pm }

Frainy is Rainy!

66 Valerie { 05.24.17 at 6:47 pm }

It’s been an unusually wet, frainy, to the point of flooding, to make national news. Yet, confirmed the lightning bugs are out in Republic, Missouri!
Yes, I caught them as a kid, only to find them at the bottom of the jar the next morning. So when my kids were young, they caught them, brought them in, and let them go in their rooms…to watch them fly! Yet, still sadly, the next day to have found, they still die. (They learn, in just one summer.)

67 Carroll { 05.24.17 at 5:03 pm }

I live in Western North Carolina, haven’t seen any lightning bugs so far this year. I enjoy seeing them, makes me feel like a kid again!

68 Peggy { 05.24.17 at 3:44 pm }

We do not have them here in western Washington state, do not know if they do in eastern Washington state but don’t think so.

I saw them only one time in my life when I was visiting relatives in Trenton, Illinois. Thought they were pretty neat to watch. Didn’t want to catch them but loved watching them.

69 Debbie Johnson { 05.24.17 at 3:18 pm }

Saw a few a couple of nights ago in Benton Arkansas. But we have had an unusual wet cool spring, so far anyway, but you know what they say about Arkansas weather, “stick around, it’ll change!”

70 Phyl { 05.24.17 at 1:37 pm }

We need to show respect for these fireflies. NOT capture them in a jar! Not harm them! Parents must teach children respect for these creatures.

71 roy o { 05.24.17 at 12:34 pm }

Had 1 in my LR on the eve of 5/18/17 in Wind Gap Pa w/ hi/lo temps that day of 90/66

72 Sandy Johnson { 05.24.17 at 7:42 am }

I saw fireflies in my backyard on May 20, 2017. In fact, one person present was surprised to see them but now we know why! Thanks.

73 Keith giffin { 05.24.17 at 7:23 am }

Yep had fire files last night 5/23/17 in south central ohio

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