About Jeff Masters
Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather
By: Dr. Jeff Masters , 4:44 PM GMT on August 30, 2012
Slow-moving Tropical Storm Isaac continues to hammer coastal Louisiana, Mississippi, Alabama, and Florida's Panhandle with tornadoes, torrential rains, high winds, and a damaging storm surge. Over the past 24 hours, destructive tornadoes have touched down in Biloxi and Pascagoula, Mississippi, and one person was killed by a tree falling on a car in Pearl River County, Mississippi. A major flood event is occurring in Slidell, Louisiana, where Isaac's storm surge filled Bayou Bonfouca and the W-14 Canal, inundating portions of the city with 1 - 5 feet of water. While Isaac is now a weakening minimal-strength tropical storm, it is still a potent rainmaker, and will cause damaging floods all along its path for the next three days. Major river flooding is occurring or is about to occur on a number of rivers in the landfall area. In north central Tangipahoa Parish in southeast Louisiana and southwestern Pike County in southern Mississippi, a mandatory evacuation has been ordered for all low-lying areas and along the Tangipahoa River, due to the potential failure of the Lake Tangipahoa dam. Audubon Park in New Orleans, recorded 11.19" of rain as of 7 pm Wednesday night. An earlier amount of 19" was found to be erroneous, and this is not a 24-hour precipitation record for the city. According to wunderground's weather historian, Christopher C. Burt, New Orleans' greatest 24-hour rainfall on record is 14.01" on July 24 - 25, 1933. The Louisiana official state 24-hour record is 22.00" on Aug. 29, 1962 at Hakberry, although U.S. Army Corps of Engineers `Storm Studies' mentions a 23.80" falling in a 24-hour period at Millers Island during a TS on Aug 7-8, 1940. Storm total was 37.50" over a 60-hour period there during that event.
A few other rainfall totals from Isaac, through 11 am EDT on Thursday:
15.02" Marion, MS
10.09" Hattiesburg, MS
10.15" Gulfport, MS
9.80" Slidell, LA
9.74" Biloxi, MS
8.52" Mobile, AL
5.57" Baton Rouge, LA
Figure 1. Isaac's winds and storm surge overcomes the seawall and floods South Beach Boulevard in Waveland, Miss., Wednesday, Aug. 29, 2012, the seventh anniversary of Hurricane Katrina hitting the Gulf Coast. (AP Photo/Rogelio V. Solis). Waveland experienced a storm surge in excess of 5' for 36 hours.
Isaac's storm surge winds down
Storm surge levels along the coast of Mississippi and surrounding areas are gradually receding, and the surge has finally fallen below 5' at Waveland, which experienced a storm surge in excess of 5' for 36 hours. Isaac's storm surge levels were characteristic of a Category 2 hurricane, and lasted for an exceptionally long period of time. Waveland, Mississippi experienced a peak surge of 8' and peak storm tide of 9' (surge plus the natural high tide), which beat the levels that occurred during Category 2 Hurricane Gustav of 2008 (7' of storm tide.) The peak 11.06' storm surge at Shell Beach, which is in Lake Borgne, 30 miles southeast of New Orleans, exceeded the 9.5' surge recorded there during Gustav. According to an article in nola.com, Isaac pushed a storm surge of 13.6' into Lake Borgne, on the east side of New Orleans. This is not far from the 15.5' storm surge Hurricane Katrina brought to the location. It is quite possible that Isaac's storm surge might have breached levees of the east side of New Orleans, flooding areas inhabited by tens of thousands of people, had the Army Corps of Engineers not completed their $14.5 billion upgrade to the New Orleans flood defenses this year. I estimate that storm surge damage from Isaac will exceed $2 billion. Isaac has likely caused $2.5 billion in insured damage not related to flooding, insurance firm Eqecat estimated yesterday. Here were some of the peak storm surge values that were recorded at NOAA tide gauges during Isaac:
11.1' Shell Beach, LA
8.0' Waveland, MS
3.5' Pensacola, FL
4.6' Pascagoula, MS
3.8' Mobile, AL
Figure 2. A TRMM satellite 3-D view of rainfall on Aug. 28 showed a few very powerful thunderstorms near Isaac's eye were reaching heights of almost 17 km (10.6 miles.) Intense bands of rain around Isaac were occasionally dropping rain at a rate of over 2.75 inches per hour. Image credit: SSAI/NASA, Hal Pierce.
Isaac's storm surge on the Mississippi River
A storm surge estimated at 12' moved up the Mississippi in Plaquemines Parish near Port Sulphur, LA, near 8:30 pm EDT Tuesday, causing overtopping of the levees and flooding of homes in the mandatory evacuation areas behind the levees. These levees were not part of the $14.5 billion levee upgrade New Orleans got after Hurricane Katrina, and were not rated to Category 3 hurricane strength, like the levees protecting New Orleans are. Since salt water is more dense than fresh water, the surge travelled along the bottom of the river, with the fresh water flow of the river lying on top. The surge continued upriver, and before reaching New Orleans, encountered an underwater barrier in Plaquemines Parish. This barrier was constructed by the Army Corps of Engineers beginning on August 15, in order to keep salt water from moving upstream and contaminating drinking water for Plaquemines Parish and New Orleans. Salt water had made it 90 miles upriver to the outskirts of New Orleans, due to the low flow rate of the river (which had dropped 7' below average in height due to the drought of 2012.) According to a spokesperson for the National Weather Service River Forecast Office, this barrier was probably able to completely block the flow of salt water upriver due to Isaac's storm surge, and no salt water made it as far as New Orleans. However, the massive intrusion of ocean water into the river channel caused the mighty Mississippi's fresh water flow to back up for hundreds of miles. Water levels were elevated by 10' in New Orleans (103 miles upstream from the mouth of the Mississippi), 8' in Baton Rouge (228 miles upstream), and 1.4' at Knox Landing, an amazing 314 miles upstream.
Hurricane Kirk in the Central Atlantic
Hurricane Kirk intensified into a 75 mph Category 1 hurricane this morning, becoming the busy 2012 Atlantic hurricane season's fifth hurricane. With the season's mid-point of September 10 still almost 2 weeks away, we've already had 12 named storms and 5 hurricanes, which is close to what an entire season experiences in an average year (11 named storms and 6 hurricanes.) Kirk should stay well out to sea and not trouble any land areas.
Figure 3. Morning satellite image of Hurricane Kirk.
Tropical Storm Leslie forms in the Central Atlantic
Tropical Storm Leslie has formed in the Central Atlantic. Leslie's formation on August 30 puts 2012 in 2nd place for earliest formation date of the season's 12th storm. Only 1995 had an earlier formation date of the season's 12th storm. With records dating back to 1851, this year is only the second time 8 total storms have formed in August. The other year was 2004, when the first storm of the season formed on August 1 (Alex), and the 8th storm (Hermine)
formed on August 29th. Leslie is organizing quickly, and appears destined to become a hurricane before the week is out. Fortunately, Hurricane Kirk is weakening the ridge of high pressure to the north of Leslie, and Leslie is expected to turn to the northwest and miss the Lesser Antilles Islands. In the long term, it remains unclear if Leslie will follow Kirk and fully recurve out to sea. The latest 2 runs of the GFS model have predicted that Leslie will recurve out to sea and not threaten any land areas, but the latest 2 runs of the ECMWF model have predicted that the trough of low pressure pulling Kirk to the northeast will not be strong enough to recurve Leslie out to sea. Instead, the ECMWF predicts that a ridge of high pressure will build in early next week, forcing Leslie more to the northwest, making the storm a potential threat to Bermuda, then to the Northeast U.S. and Canada in 8 - 11 days.
Jeff Masters
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.
Cat 6 lead authors: WU cofounder Dr. Jeff Masters (right), who flew w/NOAA Hurricane Hunters 1986-1990, & WU meteorologist Bob Henson, @bhensonweather
1588. leftlink
Regarding the question about your avatar, Google image search reveals that it is from here:
http://futbol.wikia.com/wiki/Archivo:Fuego_Helado .gif
1587. wxmod
Link
BEIJING - China said Thursday it will take more active steps to enhance weather modification, in a bid to better serve agricultural production and disaster relief work.
The country aims to build a relatively complete weather modification system by 2020 and make significant improvements in providing basic guarantees and security management, according to a plan published on the Chinese government's website, www.gov.cn.
By 2020, China plans to increase precipitation by 60 billion tonnes annually via cloud seeding, as well as extend the coverage of artificial hail suppression to more than 540,000 square kilometers from the current 470,000 square kilometers, it said.
The government also requires local authorities to ensure weather modification services on agricultural production, exploitation of cloud-water resources, emergency response and the safeguarding of major events.
China has resorted to weather modification to prevent the usually unpredictable weather from disrupting major events, such as the 2008 Summer Olympics.
1586. LargoFl
1585. WunderAlertBot (Admin)
1584. LargoFl
1583. 7544
yeap its all wait and see right now so its not 100 sure if this one curves as the gap seems to be closing from looking at the charts above this will get interesting imo thanks
1582. tropicfreak
Read the comment again. It is from the NHC 11 am discussion which use caps.
1581. ZeusWrath
and this could be a potential weakness too
EDIT: The 11am discussion confirms what I said:
LESLIE CONTINUES TO EXPERIENCE NORTHEASTERLY SHEAR...WHICH IS
CAUSING MOST OF THE CONVECTION TO BE LOCATED IN THE SOUTHWESTERN
QUADRANT OF THE STORM.
1580. GTcooliebai
1579. scottsvb
Why do you have to use caps? people can read
1578. LargoFl
WILL MISS A TROUGH FORECAST TO DIVE OFFSHORE OF NORTH AMERICA...AND
WILL BE CAUGHT IN AN AREA OF LIGHT STEERING CURRENTS IN THE LONG
RANGE. THE MODELS CONTINUE TO SLOW DOWN AT DAYS 4 AND 5...AND THE
NHC FORECAST IS SHIFTED SLIGHTLY TO THE SOUTH AND WEST AT THOSE
TIMES.
1577. unknowncomic
1576. HurrikanEB
1575. GTcooliebai
1574. sar2401
I know, but you're ruining the pun. :)
1573. LargoFl
1572. E46Pilot
You know before the old sections were used as a road. It was part of the overseas railroad built by Henry Flagler, which was untimely destroyed by.....a hurricane.
1571. KEEPEROFTHEGATE (Mod)
12L/TC/L/CX
MARK
15.27N/49.89W
1570. tropicalmommie
I would have to disagree with you there. I have been in Key West for seven years and have learned that alot of the locals here are just like the locals in my home town of New Orleans, "they don't evacuate"
1569. xtremeweathertracker
I agree Largo....most of the CV storms this season have all gone farther west than early model runs depict! Isaac for example was supposed to recurve!! Storms that stay weaker will trend farther west with time and Leslie is staying weaker than forecast so far!!
1568. aspectre
Could just hang apartments beneath the OverseasHighway...
...and on top of the old sections
Absolutely killer views, and it ain't as if they're using the old sections anyways.
1567. GTcooliebai
1566. SrChiefFan1
First, not really. Conchs are notorious for staying. Second...regardless of whether they evacuate or not, the financial impact of massive flooding would still be there....
1565. wxchaser97
Click for loop
1563. AegirsGal
1562. GTcooliebai
Leslie Long Floater - Visible Imagery Loop
1561. LargoFl
1560. ZeusWrath
the models say anything on "future" him yet??
1559. Charmeck
1558. Chucktown
Link
1557. LargoFl
1556. goalexgo
1555. ncstorm
1554. LargoFl
1553. 7544
and could block the wnw turn ?
1552. aspectre
meh, NewOrleans needs a new Dome anyways... a big yellow one.
"We all live in a Yellow Submarine, a Yellow Submarine, a Yellow Submarine..."
1551. LargoFl
1550. stoormfury
1549. KEEPEROFTHEGATE (Mod)
1548. BDAwx
While many homes would be little worse for the wear, trees and infrastructure would be crippled. Additionally, gusts can be one-two categories higher than the sustained winds and so roof damage would be widespread. - eg. Hurricane Fabian 2003
Plus, since everything is so expensive, not many homes/buildings/infrastructure would have to be damaged for a storm to cost us millions.
1547. stormpetrol
3 hours earlier
1546. SrChiefFan1
You do realize that your statement would cover the Keys? They have had a history of being completely underwater with significant devastation. So do you think the government should start forcing relocation of the folks living in the Barrier Islands know as the Keys?
1545. ncstorm
1544. SherwoodSpirit
Ohhh! RAIN!
For Friday Night: "Overcast with rain. Low of 70F. Winds from the SE at 10 to 15 mph. Chance of rain 100% with rainfall amounts near 2.3 in. possible."
Ohhh! LOTSA rain!
Hello Isaac, goodbye Drought. You will not be missed. :)
1543. AegirsGal
1542. sar2401
Certainly not in my lifetime, which I suspect is a lot shorter than yours. Emergency planning is never proacvtive, always reactive. It takes the "Big One" before people start to pay attention and move on their own. Some towns on the Mississippi River did, in fact, relocate to higher ground after being repeatedly flooded. As long as the states and federal governments continue to offer insurance to people living in flood plains, this will be a never ending problem. With a city as large as NOLA, along with all the cultural and racial issues involved, the answer will be to continue to spend billions to improve flood protection while displacing no one. One of the "advantages" of living in a dictatorship is the government can do as it pleases, like the Chinese displacing 1.3 million people so they could build the Three Gorges Project. In a nominal democracy, people have to make, or at least go along with, the decisons. There's no easy answers here, but refusing insurance is a first step.
1541. 7544
yeah if you notice this gfs run by the time leslie is at 25 lat east of the us it has another system over fla just like the euro showed looks like its the remains from issac or split moving sse interesting
1540. LargoFl
1539. stormwatcherCI
1538. LargoFl