Hurricane Isaac – severe floodingAugust 28th, 2012 at 12:22 pm by Bill Steffen under Bill's Blog, Weather
10:30 PM - Audubon Park reports 18.70″ of rain as of 7PM local time. However, the airport reported only 7.41″ and the lakefront in N.O. reported 8.4″ of rain. With the strong winds, it’s hard to get an accurate read, and the 18.7″ may be high. …levees and pumps holding up well so far – areas south of N.O. have taken a real beating. 10 PM observations show 40-50 mph gusts from Baton Rouge to the south and along the Mississippi Coast. The Waveland MS Yacht Club reported a gust to 65 mph around midday. Look at rainfall forecast from GFS model – 6-9″ south of Chicago?! Rain to the Michigan border. We’ll see. The Coast Guard confirms that around 1 a.m. a barge broke loose in Chalmette, hit and sunk a 47-foot crew boat. Isaac is pretty much stalled just northwest of Houma, Louisiana along the coast. The eye of the storm is still well intact and around 35 miles wide. The main threat continues to be heavy rain and significant flooding. A levee has been topped near Belle Chasse and there are evacuations and rescues in progress there. One father-son team has already rescued 23 people. The town of Braithwaite has been inundated with 10-12 feet of water, chasing those that stayed behind to their attics and rooftops. Rescues continue in Plaquemines Parish (over 75 already), where people are huddled on levees waiting for boats to get them out. What’s frustrating to emergency workers was that this area was under a mandatory evacuation – yet so many refused to leave. The Woodlawn Fire Station is under five feet of water. “Widespread and significant flooding” is reported in downtown New Orleans. Official says: “”So much more damage than Katrina here in Plaquemines Parish”. Here’s rainfall totals up to 7 AM CDT. Many streets are impassible due to downed trees and flooding. The New Orleans Airport has had 9 hours with wind gusts of 60-70 mph and they are still getting gusts of 55-60 mph. The Federal Government spent 14 Billion Dollars repairing and replacing levees after Hurricane Katrina in 2005. A weather station at the ferry dock at Belle Chasse measured a wind gust of 113 mph! A Gust to 110 mph was reported at Bayou Gauche. Over 653,000 customers are without power. Here’s New Orleans webcams. A Tornado Watch continues for SE Louisiana, S. Mississippi and extreme SW Alabama. Peak winds: Southwest Pass reports the sustained (steady) wind at 69 mph with gusts to 85 mph, 77 mph at Galliano, 75 mph at Boothville…earlier: 85 mph at Grand Isle. Grande Isle mayor says “All Hell is breaking loose” ( his words). St. Bernard Parish reports many trees blocking roadways, making driving nearly impossible. Video here. Note the hurricane on the U.S. Wind Map. Global satellite image. Tweet from actress Ruth Buzzi: “James Carville laughed about it hitting Tampa & the RNC so now Hurricane Isaac‘s strolling down Bourbon Street. Never mess w/ Mother Nature.” Video from Reed Timmer of 11-foot storm surge at Waveland MS. Isaac has shut down 93% of U.S. oil production in the Gulf of Mexico and 67% of natural gas production. Mississippi storm surge. I-10 is blocked by floodwaters near LaPlace. Tweet from Senator Vitter (R-LA): “Drive to 17th St. Canal: saw lots of downed trees, debris. Persistent wind & rain continues. Almost no electricity in homes visible” Tweet from Rep. Ted James of Baton Rouge: “Isaac has the potential to have a greater impact on BR than Gustav. We have never experienced sustained winds for this long a period of time.” Isaac from the Intl. Space Station.
New Orleans observation at 12 Midnight Weds. EDT: N.O. LAKEFRONT HVY SNOW N/A N/A N/A NE53G69 29.34F VSB 1/4 HUH? SNOW???? The visiblity is 1/4 mile in rain (and blowing rain). The sensor thought it was snow! A buoy east of the mouth of the Mississippi River (KMIS) reported a gust to 92.1 knots – that’s 106 mph. Two Humane Society Shelters evacuated all of their animals before the storm hit. There have been animal rescues, but far fewer than with Katrina. Dogs in particular are very resilient and usually find a way to survive hurricanes. More links: New Orleans Radar, Mobile AL radar, Jackson MS radar, Gulf Regional Radar, current weather observations from Louisiana (67 mph at Boothville – near the mouth of the Mississippi River – before the weather station failed). Both stations had sustained (steady) winds of over 45 mph). Here’s storm reports from SE Louisiana. Here’s where you can get weather data from dozens of buoys in the Gulf of Mexico. New Orleans has already had 8.45″ of rain this month, so there will be significant runoff. The remnant moisture from Isaac will move north and then northeast up into Indiana over the weekend. Combined with a weak front coming down, this will give Southern Lower Michigan a chance of showers/t-showers Saturday (too early to tell for sure). Keep coming back to this thread to use the links below. We now have Tropical Storm Kirk. Typhoon Bolaven has left 16 dead in Korea.
The new European model gives G.R. no rain until next Monday night, and then only .09″. The NAM is dry thru Saturday for G.R. (as far as it goes out). The GFS has about .60″ of rain Saturday and Sunday.
The fastest gust I saw Sunday was 70 mph at the Smith Shoal Lighthouse and 66 mph at Virginia Key…also gusts to 56 mph at Molassas Reef, 58 mph at Sombrero Key, 52 mph at Key West and Boca Chica and 51 mph at Port Everglades. Here’s storm reports from Miami and Key West. Here’s the latest track on the storm from the National Hurricane Center (they have adjusted the track to the west and will likely do that again. The combination of warm water/significant intensification and the proximity to New Orleans brings the possibility (not probability) of a Katrina-type situation with the strong SE winds on the right side of the storm pushing water into Chandeleur Sound, the Intracoastal Waterway and Lake Ponchartrain. Check out the path of Katrina, first crossing S.Florida and then intensifying into a Category 5 storm before weakening as it came onshore in Louisiana. A Hurricane Watch is now in effect all the way west to Morgan City LA. This also means that hundreds of offshore Gulf oil platforms will be shut down and that could affect the price of gasoline. High Wind Probability Map,the Funktop Satellite loop, Visible (to IR at night) satellite loop, SE U.S. looping regional radar.
Here’s current weather observations from S. Florida. The Keys are getting gusts of 40-60 mph and occasional heavy rain/squalls. Here’s S. Florida radar. The storm center of the storm center moved through the Keys. The storm will intensify as it gets out over the warm Gulf waters west of the Florida Peninsula. One fatality was reported in the Dominican Republic and nine deaths in Haiti. The harbor at Port au Prince in Haiti is more shielded when storms pass south of them, so there was no storm surge there. The Gulf of Mexico is quite warm, with water temperatures of around 86 degrees. That will help the hurricane to intensify into a Category 2 storm. The Republican convention will delay almost all activity on today, with a day and a half of windy, rainy weather. Tampa has had a wet summer and there may be some local ponding/flooding. Since June 1st, Tampa has had 32.9″ of rain before Isaac arrived! The governor of Florida and the mayor of New Orleans have declared States of Emergency in advance of the storm. A Tornado Watch will be issued for much Florida. Here’s a map of the last strong hurricane to hit each of the SE states. All the states in the SE have Republican governors (except NC and AR), so a few of those governors may have to tend to hurricane business more than convention business. Often the ridge gets pumped up ahead of hurricanes which would favor generally dry weather and warmer than average temperatures from Tues. on next week in S. Michigan. Here’s the Public Advisory, Forecast Advisory, Forecast Discussion, Caribbean weather map, Funktop Satellite Loop, Visible Satellite Loop, Barbados radar, Antilles islands radar, and radar from Puerto Rico, Here’s radar from Miami, Key West, Melbourne (central Florida, east coast), Tampa (central Florida, west coast), Jacksonville and Tallahassee. Here’s tropical cyclone names for this year through 2017. Here’s a summary of the tropical storm season of 2012. Cuban Weather Observations, and Cuban Radar. Here’s webcams from the Florida Keys. More Florida webcams.
Tornadoes are a possibility as Isaac comes into the SE U.S. There has been a Tornado Watch for much of Florida. SPC says: ” THE PRIMARY FOCUS FOR THE OUTLOOK PERIOD WILL BE ON TROPICAL SYSTEM ISAAC…WITH THE PERIPHERAL OUTER BANDS OF ISAAC LIKELY TO AT LEAST GRAZE MUCH OF FL ON DAY 4/MONDAY BASED ON THE LATEST NHC FORECAST TRACK/INTENSITY. AS SUCH…A TORNADO THREAT WILL BE A DISTINCT POSSIBILITY FOR PORTIONS OF FL ON DAY 4/MONDAY…ALTHOUGH CONFIDENCE DOES NOT EXIST IN 30 PERCENT EQUIVALENT SEVERE/TORNADO PROBABILITIES AT THIS TIME. THEREAFTER…EARLY INDICATIONS ARE THAT TORNADO POTENTIAL COULD CONTINUE INTO DAYS 5-6 TUESDAY/WEDNESDAY ACROSS THE CENTRAL GULF COAST/SOUTHEAST STATES…”
Also, a great read (with video) on Hurricane Andrew from the NWS in Miami, which hit just south of Miami 20 years ago.
And, if you haven’t seen the sign that is dancing in 60 mph wind gusts in Calgary Alberta…the sign breaks and barely misses the car shooting the video. Here it is.
Regarding Joyce, this is another example of the naming of storms that would not have been named before (Florence, Helene – a couple others it was questionable that they were tropical). The ACE Index (Accumulated (Tropical) Cyclone Energy) is a good way to climatologically track tropical cyclones (formula here). The ACE Index peaked in the late 1990s and has been trending downward since then.