Dr. Jeff Masters' WunderBlog

Katrina's 2nd anniversary, and the tropical update
Posted by: Dr. Jeff Masters, 2:31 PM GMT on August 29, 2007 +3
A tropical wave midway between Africa and the Lesser Antilles (94L) has changed little since yesterday. QuikSCAT data from 4:47am EDT this morning shows a poorly organized system with a weak, elongated circulation. Top winds were 25 knots (29 mph). Visible satellite loops show a limited amount of disorganized thunderstorm activity. Wind shear is a favorable 5-10 knots over 94L, and should not be a problem for it until Friday or Saturday. By then, 94L will be moving through the Lesser Antilles Islands, and may encounter high wind shear if it is far enough north to feel the winds of an upper-level low pressure system that will be just north of Puerto Rico.

The presence of a large, dusty area of dry air surrounding its north side is the main thing holding back 94L. This dry air is being sucked into the circulation and is interfering with the storm's organization. When the dry air encounters a thunderstorm inside 94L, this denser dry air gets incorporated into the thunderstorm's downdraft, accelerating the downdraft, and creating arc-shaped surface cumulus clouds that mark the downdraft's position as it spreads out along the ocean surface (Figure 1). The presence of these arc-shaped surface clouds is usually a good sign that a storm is struggling with dry air and will not intensify significantly for at least the next 12 hours.

Water vapor satellite loops of the region show that 94L has not significantly moistened its environment. As the storm continues further west, it should be able to gradually do so, allowing it more of a chance to get organized. The system should track through the Lesser Antilles Islands on Friday, which is the earliest day I expect it could become a tropical depression. None of the reliable computer models make a believable forecast showing 94L developing into a tropical depression before it reaches the Lesser Antilles. The GFDL develops 94L into a tropical storm once it makes it into the central Caribbean south of the Domincan Republic, and this is a believable forecast, if 94L hangs together and makes it into the central Caribbean. The Hurricane Hunters are on call to investigate 94L on Friday.


Figure 1. Visible satellite image of 94L, show arc-shaped outflow boundaries from thunderstorm downdrafts.

South Carolina low
An area of low pressure has developed a few hundred miles off the South Carolina coast, along an old frontal boundary. This disturbance has been designated "95L" by NHC this morning. QuikSCAT showed a sharp wind shift but no closed circulation around 95L this morning at 6:34am EDT, and measured winds as high as 50 mph. Wind shear is about 15 knots over the disturbance, which is drifting south into a region where wind shear is expected to remain low enough to allow some development this week. I do think 95L will become a tropical depression, and most of the computer models also agree on this. The models disagree substantially on 95L's track, though. Steering currents will be weak in its vicinity, and 95L may spend a number of days wandering erratically. The Hurricane Hunters will investigate 95L Thursday afternoon.

Coast of Africa
The UKMET model is indicating the possible development of a tropical depression by Friday off the coast of Africa. There is a large surge of moisture with at least one strong tropical wave embedded in it coming off the coast of Africa this week, and it would be no surprise to see this wave develop into a tropical depression.

Katrina, two years later
Two years ago today, on August 29, 2005, Hurricane Katrina smashed into the Gulf coast with Category 3 winds and an incredible storm surge up to 27.8 feet high. Wunderblogger Mike Theiss was at ground zero in Gulfport, Mississippi during Katrina, and has posted a blog this morning on his experience, complete with some very compelling photos. His video of the storm surge washing into the hotel he was at is the most amazing storm video I've ever seen.

Margie Kieper's Katrina's Storm Surge feature on our tropical page provides an extraordinarily detailed 16-part examination of each portion of the coast devastated by Katrina. Margie is scheduled to be a guest on the Talking Tropics Internet radio show Thursday night to talk about Katrina's storm surge. Check the listings to see if there are any last minute changes.


The photo above was taken from Part 8: Lakeshore to Waveland, MS of Katrina's storm surge. An excerpt from the text:
I found an astonishing photo, of the peak of the surge in Waveland, which didn't appear to be faked, but I'm pretty much of a skeptic. The photo had this caption, "Photo taken in Waveland, MS, just North of the Railroad Tracks during Katrina around 9 AM by Judith Bradford." Note that it is being taken from the second floor window of a home, and that the water is close to the roof line of the first floor. There is a man perched on what is left of a home across the street, wearing a tiny life jacket and clutching a neon green pool noodle. There are electric lines running down from a pole to a home from left to right. In the distance on the right is a home with water up to the roof line. It is likely after 9am, as the bulk of the surge came between 9 and 10 am (that is when most of the fatalities occurred along the Mississippi coast), and probably the eye is already overhead, as the water is relatively calm and there appears to be little wind or rain, even though the pine trees are bent from the recent force of the eyewall winds.

The information provided by the Bradfords regarding the surge was very specific. The power went out at around 6:30am at their Waveland home on the morning of the 29th. They were staying in the home for a couple of reasons; first, because the home had not received any water at all from Camille, and, secondly, because both work in the medical field and needed to be available after the storm. At almost exactly 8:30am, water started coming over the railroad track embankment, from the coast, and into their yard.

Their home is 18 inches off the ground, and the first floor has 8-foot ceilings. There is an 18-inch truss between the 1st and 2nd floors, and this is what saved their 2nd floor from being flooded. In a matter of only five to ten minutes the water came up six feet, and quickly filled the first floor after that. Judith said that is why they saved so little from the first floor; they had no time to get anything. She first tried to shut the living room front door, but the force of the water burst the door open. She grabbed a camera and the Bradfords and their children ran upstairs. They marked the high water mark (HWM) on the inner stairwell showing how high the water came ? a little more than six more inches into the truss, which is a total of 10 feet of surge.

They saved two other people besides the man who was floating by on the roof in the photo. He was a chef named Glen, holding a four month old dachshund named Pinky, in the surge. He had lost his other dog and three cockatiels when his mother's home collapsed. The roof wedged against their van, underwater, and stopped, so they were able to save him. Bill Bradford told me when he swam out to rescue that man, that the water was so warm it seemed almost hot. He said the current was nothing like white water, but was a gentle continuous flow.

Because their home is right by the railroad tracks, it is not as high in elevation as I had thought. It is around 17 feet elevation. That is close to the HWM observed in Pass Christian, 27 feet.

With such a good quality HWM, I wondered why their house was not surveyed. Judith Bradford told me that no one from the federal government seemed to realize their house was there. The road leading up to Jeff Davis (they own 6 ½ acres and raise miniature horses, which were drowned in their stables when the surge came) was filled with debris. The teams doing Search and Recovery for bodies didn't even check the house because they didn't know it was there; it was a good thing the family survived!

The water started to go down sometime after 11am, and by noon was about chest high, and by 2pm about waist-deep. The water finally left the house completely by about 4 or 5 pm that evening. She believes the railroad track embankment kept the water from receding faster. "


I'll have an update Thursday morning, unless there's a major change in 94L or 95L. My thoughts and prayers are with all those affected by Hurricane Katrina today. Let us not forget what happened two years ago.

Jeff Masters

  Permalink | A A A
Reader Comments
Display: 0, 50, 100, 200 Sort: Newest First - Order Posted
Viewing: 251 - 301

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25Blog Index

251. NaturalDisaster 6:25 PM GMT on August 29, 2007    
Wow looks like 95L will develop acording to Dr. Masters he stated "I think 95L will develop"...Also its possible it will be a land falling storm...its drifting south towards the warming waters and less shear....UH OH
252. stormygace 6:26 PM GMT on August 29, 2007    
katadman - rode the pygmy pony & watched for the yellow snow in earlier days ...
VaSurfer - we've got some sand bars here that will give good breaks & a coquina outcropping that is often mighty fine
miken62 - hypocrisy really ticks me off - if I thought for one minute that troll was a sincere John Birch Society member who takes care of himself & his w/o looking for his "entitlements" I wouldn't have grabbed the bait. Ticks me off that as a nation we so poorly look out for our own but are h*ll bent on running around the world to provide "aid & relief".

Sooo...which invest gets a name first (staying on topic lol)?
Member Since: September 7, 2005 Posts: 23 Comments: 1084
253. katadman 6:27 PM GMT on August 29, 2007    
Posted By: NormalGuy at 6:23 PM GMT on August 29, 2007.

Hey watch it, I wear white socks with sandals, oops nevermind that is just my feet with no tan...Come on guys this strummer guy just walked in and caught his wife in bed with someone else or something like that just having a bad day and he probably is too small to yell at anyone face to face, ignore him and he will leave.


ROFLMAO: HILARIOUS!!!
Member Since: September 7, 2006 Posts: 0 Comments: 1081
254. srada 6:28 PM GMT on August 29, 2007    
SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
DEVELOPING AND STRENGTHENING LOW PRESSURE WELL OFF THE SOUTH
CAROLINA COAST WILL KEEP A NORTHEAST TO EASTERLY FLOW AT THE
SURFACE ACROSS THE AREA THIS PERIOD. THIS AREA OF LOW PRESSURE IS
EXPECTED TO DRIFT S BEFORE GETTING PICKED UP BY EAST COAST TROUGH
AND TRACKING TO THE NE BEGINNING LATE IN PERIOD. SUBSIDENCE ON
BACKSIDE OF THIS AREA OF LOW PRESSURE SHOULD TEND TO LIMIT CLOUD
COVER AND RISK OF SHOWERS AND THUNDERSTORMS ACROSS THE FORECAST
AREA. HOWEVER...WEAK SHORTWAVES EMBEDDED IN NW FLOW ARE EXPECTED
TO MOVE ACROSS THE AREA...BUT MODEL TIMING AND INTENSITY IS
SUSPECT AT THIS TIME. THEREFORE... ALTHOUGH NO POPS WERE INCLUDED
TONIGHT...CAN NOT RULE OUT AT LEAST A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS BEGINNING THU AFTERNOON AND THEN THROUGH THE
REMAINDER OF THE PERIOD AS MID LEVELS STRUGGLE TO MOISTEN UP. AT
THIS TIME...HIGHEST POPS ALONG AND W OF I-95 APPEARS MOST
REASONABLE THU AND THU NIGHT WITH NO ONE AREA PREFERRED OVER
ANOTHER ON FRI. SHOWERS AND THUNDERSTORMS AHEAD OF A PRE-FRONTAL
TROUGH SHOULD REMAIN N AND W OF THE AREA TIL JUST BEYOND THE
FORECAST PERIOD.
Member Since: August 17, 2006 Posts: 1 Comments: 772
255. zingocat 6:30 PM GMT on August 29, 2007    
hello, I am lurking again here in NC. Remember I don't like the F word storms.
Member Since: July 15, 2007 Posts: 0 Comments: 170
256. SavannahStorm 6:30 PM GMT on August 29, 2007    
When did Weather Underground become Homeowner's Insurance Underground?
Member Since: September 22, 2005 Posts: 18 Comments: 2135
257. runningfromthestorms 6:30 PM GMT on August 29, 2007    
Jstrummer - what about people who live in major cities near rivers that flood or on the earthquake prone West Coast or near Mt St Helens or in Tornado alley? Should we say anyone near a natural recurring threat is an idiot and should be barred from aid/insurance????? where would we live? we bear our fair share of the cost down here. I pay 12K a year in insurance and figure it is fair with my 30K deductible. I also pay my taxes every year. I am one the tax payers you are talking about shouldering the burden and if I ever need assistance after a hurricane it will be the only assistance I ever get from the gov't or anyone else in my family ever gets from the gov't. I pay property tax, income tax, gas tax, ss tax, sales tax etc as do all the other people down here (or most of them anyway)......so if I or anyone else who lives down here ever makes a claim for help what is it to you? We help pay for assistance to other areas of the country in their times of need with our taxes and insurance dollars. We contribute more than we get. There's two sides to this story.
Member Since: July 31, 2006 Posts: 0 Comments: 99
258. floridagrrl 6:30 PM GMT on August 29, 2007    
Posted By: NormalGuy at 6:23 PM GMT on August 29, 2007.

Hey watch it, I wear white socks with sandals, oops nevermind that is just my feet with no tan...


Still laughing...On that note, I must take a break and do mom stuff. And maybe I'll call a realtor and move to Montana...

And 95l is a tease, tripping down the coast like this; too much. That just shouldn't happen, fascinating stuff. Good day.
259. NaturalDisaster 6:32 PM GMT on August 29, 2007    
Since there is nothing what-so-ever steering 95L Models are crazy right now taking it in complete loops, I remember Jeanne in 2004 or 2005. Everyone let there guards down in florida because it was turning away....and since there was really no steering currents...much like 95L...95L could do a jeanne like track.
260. druseljic 6:34 PM GMT on August 29, 2007    
Getting some much needed rain in the panhandle. Watching 94L, it may have some obstacles but imo its worth watching.
Member Since: August 13, 2007 Posts: 0 Comments: 649
261. rwdobson 6:34 PM GMT on August 29, 2007    
"95L could do a jeanne like track."

uhh, go back in look in the archives. jeanne formed in the lesser antilles, not off the carolina coast. so it's not really like 95L at all.
Member Since: June 12, 2002 Posts: 0 Comments: 1574
263. SavannahStorm 6:35 PM GMT on August 29, 2007    
The track that Ophelia took did some funny things, too, a couple of years back.
Member Since: September 22, 2005 Posts: 18 Comments: 2135
264. nash28 6:36 PM GMT on August 29, 2007    
LOL Savannah!!!
Member Since: July 11, 2005 Posts: 190 Comments: 16972
265. presslord 6:36 PM GMT on August 29, 2007    
this kinda reminds me of Gaston a couple years ago
Member Since: August 13, 2007 Posts: 0 Comments: 10377
266. will40 6:38 PM GMT on August 29, 2007    
Posted By: SavannahStorm at 6:35 PM GMT on August 29, 2007.

The track that Ophelia took did some funny things, too, a couple of years back.


This thing has Ophelia written all over it
Member Since: September 19, 2005 Posts: 2 Comments: 3439
267. watchinwxnwpb 6:38 PM GMT on August 29, 2007    
Good Afternoon everyone! I just wanted to apologize for my rant w/Jstummer! Usually I am very even tempered...I guess that just was the last straw. The Florida bashers were out in full force a couple of weeks ago & I finally let one get to me! So, I apologize again to the good folks on here! runningfromthestorms your post was very eloquently executed! Anyway, looks like things are cooking right now! Lot's of stuff to watch! As we all know to well, things can change quickly, so we'll all have to keep watching!
Member Since: September 15, 2006 Posts: 0 Comments: 421
268. Bonedog 6:38 PM GMT on August 29, 2007    
95L will be churning and burning shortly. Pay attention after it does a disapation stage as it decouples from the front and turns warm core. This storm is going to stall right over the gulf stream for a few days before being moved by anything. Just hope the BA/AZ High doesnt decide to move west and push this bugger twords land before a front can kick it away.

This will surprise folks. I hope they do fly the HH into it tomorrow. Seems folks only pay attention to named systems.
Member Since: July 14, 2005 Posts: 14 Comments: 7418
269. puffdraggon 6:41 PM GMT on August 29, 2007    
I lived in an official "no flood" zone (flood zone C) 1.5 to 2 miles from the beach in Bay Saint Louis, MS. High and dry according to the flood maps and all infomation I could get. Not even close to flooding during Camille. Well, I got over two feet of water in my house! Moral: no matter how smart you may think you are, mother nature still has plenty of tricks up her sleeve. So when good ol' Strummer gets his rear end frostbit way up north I won't bother to send a sympathy card, that's for sure....
270. NormalGuy 6:41 PM GMT on August 29, 2007    
Well, this is unusual, i got on here and thought for sure this blog would be hard to keep up with. A couple of invests out there this place should be busier than wal-mart on the first. Oh well thats good, i can read and stay caught up this way. By the way, a man walked into the voo-doo doctors office and asked if he could remove a curse, the doctor said sure if you know what line was used to place the curse on you, the man said thats easy the line was "i now pronounce you husband and wife"...A little humor never hurt anyone...
271. StormJunkie 6:42 PM GMT on August 29, 2007    
Afternoon all ☺

Hey press, yea getting insurance down here can be a real pain. Especially that close to the shore.

Holy mackerel Bob Hart is going off with the MM5's. Interesting initialization data, I will be very curious to see how they perform.

Quick Links-Forecast models, imagery, marine data, wind data, preparedness info and much more.

Only on break here, got to get back to work. See y'all in a couple of hours.
Member Since: August 17, 2005 Posts: 26 Comments: 15218
272. StormJunkie 6:43 PM GMT on August 29, 2007    
I would also love to see a spaghetti plot of all of the MM5's together. Anyone know where to find something like that? If so, please shoot it over in WU mail.

Thanks and see y'all soon!
Member Since: August 17, 2005 Posts: 26 Comments: 15218
273. groundswell 6:43 PM GMT on August 29, 2007    
Bonedog-95L you know this will provide days of waves for Jersey to Florida: And if it strenthens, well, could be some size too.
Member Since: August 28, 2006 Posts: 0 Comments: 381
274. watchinwxnwpb 6:43 PM GMT on August 29, 2007    
NormalGuy...rofl. Indeed, humor is a good thing!
Member Since: September 15, 2006 Posts: 0 Comments: 421
275. TerraNova 6:45 PM GMT on August 29, 2007    
MODIS just passed over the Yucatan system:

terramodis
Member Since: July 30, 2007 Posts: 76 Comments: 4058
276. nash28 6:45 PM GMT on August 29, 2007    
The reason the blogs are not crazy is because the "reliable models" do not really develop either system into anything major.

I think that took the wind out of the proverbial sails of some folks...
Member Since: July 11, 2005 Posts: 190 Comments: 16972
277. watchinwxnwpb 6:46 PM GMT on August 29, 2007    
Hey Nash! Good to see you! What's your take on 95L?
Member Since: September 15, 2006 Posts: 0 Comments: 421
278. druseljic 6:48 PM GMT on August 29, 2007    
Nash a question if you will. Which are the reliable models. There seem to be so many. Thanks!
Member Since: August 13, 2007 Posts: 0 Comments: 649
279. hurricane23 6:49 PM GMT on August 29, 2007    
This thing will be drifting in all sorts of ways in the coming days according to the models.

fff
Member Since: May 14, 2006 Posts: 8 Comments: 13278
280. druseljic 6:51 PM GMT on August 29, 2007    
Well I definitely agree with the models for 95L this time, I don't know where its going either, lol!
Member Since: August 13, 2007 Posts: 0 Comments: 649
281. Bonedog 6:51 PM GMT on August 29, 2007    
groundswell your right. Should be a nice wave generator. Nothing up here yet and nothing on the long range bouys yet. Hopefully in time for Lbor Day. I still need to get my stick back from the shaper though :( Hopefully it will be ready.
Member Since: July 14, 2005 Posts: 14 Comments: 7418
282. VaSurfer 6:51 PM GMT on August 29, 2007    
Hatteras Island NC already seeing a new SE background swell from 95L. This strom will definately be a swell maker. Already 14 feet @ 7 seconds, thats crazy!
283. nash28 6:51 PM GMT on August 29, 2007    
95L is a tricky one to call. It depends on the trough and the positioning of this system.

Member Since: July 11, 2005 Posts: 190 Comments: 16972
284. Bonedog 6:52 PM GMT on August 29, 2007    
14 feet!!! Gees I need to drive to Hatteras. I have 2 foot wind slop here.
Member Since: July 14, 2005 Posts: 14 Comments: 7418
285. weathers4me 6:53 PM GMT on August 29, 2007    
Most spaghetti models show 95l coming partially on shore in FL. Am I seeing that right?
Member Since: May 24, 2007 Posts: 0 Comments: 112
286. extreme236 6:53 PM GMT on August 29, 2007    
Ok, just got home. I see we now have 95L, which could become a TD before 94L. TWC believes 94L could become a TD in 24-48hrs (unusual for them to say that so early). also, the nhc says that disturbance over the yucatan could develop over the BoC
Member Since: August 2, 2007 Posts: 19 Comments: 19234
287. nash28 6:53 PM GMT on August 29, 2007    
The GFS, UKMET, NOGAPS and GFDL.

Some will throw in the ECMWF as well.
Member Since: July 11, 2005 Posts: 190 Comments: 16972
288. TheCaneWhisperer 6:53 PM GMT on August 29, 2007    
Looks like the Bamm Shallow is thinking that 95L will get lost in the currents and the high will push it back to the NW.
289. TerraNova 6:53 PM GMT on August 29, 2007    
Also the latest TRMM pass confirms the banding features on 95L:

wrp
Member Since: July 30, 2007 Posts: 76 Comments: 4058
290. watchinwxnwpb 6:54 PM GMT on August 29, 2007    
Thanks Nash...I figured that would be your answer. lol Hopefully this will be a great one to watch, but no one gets affected!
Member Since: September 15, 2006 Posts: 0 Comments: 421
291. druseljic 6:56 PM GMT on August 29, 2007    
Nash thanks for the reply. I really appreciate the core group here who helps us newbies to learn.
Member Since: August 13, 2007 Posts: 0 Comments: 649
292. extreme236 6:56 PM GMT on August 29, 2007    
wow someone lit the match on the tropics lol. everything got way more active
Member Since: August 2, 2007 Posts: 19 Comments: 19234
293. Bonedog 6:56 PM GMT on August 29, 2007    
extreme I said 95 would develope yesterday and it did :) I am starting to get better at this forcasting thing LOL.

Seriously though, I think 95 has a better chance of being named before 94 only because tomorrow the HH will fly into it and it will be friday before 94 is within reach.
Member Since: July 14, 2005 Posts: 14 Comments: 7418
294. VaSurfer 6:56 PM GMT on August 29, 2007    
Well that's 14feet offshore near the Norfolk Canyon way out over the gulf stream, not 14 near shore. Virginia Beach is 1-2 foot chop as well
295. mississippiwx23 6:57 PM GMT on August 29, 2007    
The ECMWF and the GFS are usually considered as the best. The UKMET isnt bad either. The NOGAPS has trouble initiating systems, and GFDL/HREF are not run unless a storm is present, which makes them useless when trying to find potential storms in the long range.
Member Since: August 20, 2007 Posts: 3 Comments: 683
296. amazinwxman 6:56 PM GMT on August 29, 2007    
feature off of the Carolinas (95L) is probably our best candidate for our next tropical cyclone in the basin. It'll take a day or so to undergo warm core transition (or tropical transition), but by late tomorrow I expect we'll likely have something of interest. It will likely meander around in the Gulf Stream for the next few days and with weak steering currents, erratic motion can be expected. Interests from the central Florida coast northward need to watch -- but not worry -- about this one over the coming days.
297. SavannahStorm 6:58 PM GMT on August 29, 2007    
When's the next Quicksat pass over 95L?

And anyone have a link to the 14-ft wave observations. All I see in the OBX area is 2-4 ft swell.
Member Since: September 22, 2005 Posts: 18 Comments: 2135
298. BrandonC 6:58 PM GMT on August 29, 2007    
Interesting thought on the Florida State models that I was just looking at. All 3 of the models develop 95L into something and throw it into the florida east coast partially before throwing it off to the north, then NE. For now we should be more concerned with 95L then 94 if you live on the east coast of the U.S. .
299. VaSurfer 6:59 PM GMT on August 29, 2007    
I agree Nash, thanks for all you do, this Buds for you
300. TerraNova 6:59 PM GMT on August 29, 2007    
The WRF precipitation forecast model (not to be confused with HWRF) swirls 95L to the south and also throws in another spiral southeast of long island.

Link
Member Since: July 30, 2007 Posts: 76 Comments: 4058
301. StormHype 6:59 PM GMT on August 29, 2007    
Can't believe folks are already comparing 95L to Hurricane Jeanne of 2004. LOL

Member NaturalDisaster is one of the fear monger dooms day hypersters I warned you about yesterday. He must be a writer for TWC's show "It could happen tomorrow" (but probably won't)
Member Since: May 31, 2007 Posts: 0 Comments: 1163

Viewing: 251 - 301

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25Blog Index

New Comment
Community Standards Policy Comments will take a few seconds to appear.
Post Your Comments
Please sign in to post comments.
Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.
About JeffMasters
Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Community Activity