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Giovanna hits Madagascar; major damage likely

By: Dr. Jeff Masters , 1:07 PM GMT on February 14, 2012

Tropical Cyclone Giovanna powered ashore along the east coast of Madagascar as a destructive Category 3 storm with 125 - 130 mph winds at 22 UTC last night. Winds at the coastal city of Tamatave, 70 miles north-northeast of where the center came ashore, peaked at 52 mph, gusting to 71 mph. Giovanna is moving west across the island at 17 mph, and passed just south of the capital of Antananarivo as a Category 1 storm at 8 am local time Tuesday morning. The eyewall missed Antananarivo , and the peak winds in the city were 38 mph, gusting to 55 mph. Microwave satellite imagery from the Navy Research Lab in Monterrey showed that Giovanna had rainfall rates of up to one inch per hour at landfall, and it is likely that the storm dumped 5 - 10 inches of rain along much of its path. The heaviest rains fell on deforested mountain slopes that drain into some of the most densely populated regions on the island, so major flood damage is likely. Heavy wind and storm surge damage undoubtedly occurred where the core of the storm hit the island, as well.


Figure 1. Visible image from NASA's Terra satellite of Tropical Cyclone Giovanna over Madagascar, taken at 7:15 UTC Tuesday February 14, 2012. Seven hours previous to this time, Giovanna was a Category 2 storm with 110 mph winds, but had probably weakened to a Category 1 storm by the time this picture was taken. Image credit: NASA.

The forecast
Passage over the rugged terrain of Madagascar has significantly weaken Giovanna, and the cyclone will move into the Mozambique Channel between Madagascar and Mozambique as a tropical storm later today. Latest computer model forecasts from the GFS and ECMWF models suggest Giovanna may reintensify over water, and swing around and pass very close to the south tip of Madagascar early next week. Meanwhile, Madagascar must also keep an eye on Tropical Cyclone Thirteen, which is gathering strength over the waters to the east of the island, and is on a course that will bring it close to Madagascar this weekend.


Figure 2. Microwave satellite image of Tropical Cyclone Giovanna taken at 02:44 UTC Tuesday, February 14, 2012. The cyclone was still a well-organized Category 2 storm at this time, five hours after landfall. Image credit: Navy Research Lab, Monterrey.

Jeff Masters

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Quoting WxGeekVA:


Are you serious? A CATEGORY 4 hurricane was coming towards the country and they sent out guys ringing bells and yelling? I thought this was 2012...not 1612!


This is what I posted earlier on the last blog, with the link to copy and paste:-

An extract from a BBC report on the Madagascar cyclone, its a short piece but gives a bit of an idea of the reasons we have not got much information out of there:-

"Town criers, who walk around the streets ringing a bell and shouting out information in the local Malagasy language, are normally used by the government in a time of crisis.

But Mr Healy said they were not heard on Monday and it has left many people taken aback by the storm's severity."

Here's the link if anybody wants to copy and paste it?

http://www.bbc.co.uk/news/world-africa-17025328

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"Town criers...were not heard on Monday..."
~320thousand internet users out of ~21million people; with most users located in small urban enclaves.
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Quoting aspectre:
Madagascar hit by cyclone Giovanna
"The government of Madagascar issued the first warnings on Monday afternoon - but residents say the intensity of the cyclone was not explained.
Town criers, who walk around the streets ringing a bell and shouting out information in the local Malagasy language, are normally used by the government in a time of crisis. But Mr Healy said they were not heard on Monday, and it has left many people taken aback by the storm's severity.


Are you serious? A CATEGORY 4 hurricane was coming towards the country and they sent out guys ringing bells and yelling? I thought this was 2012...not 1612!
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Quoting MTWX:

I totally agree. I was just using this single tornado as an example (struck close to home). That's all it takes is one...


That's true, but at my house in at least 5 years, all we've been able to eke out is 2 or 3 45 mph wind gusts and a minute of smaller-than-pea sized hail. It really sucks.
Member Since: February 11, 2012 Posts: 0 Comments: 9871
Giovanna is beginning to build up its core again.



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Madagascar hit by cyclone Giovanna
"The government of Madagascar issued the first warnings on Monday afternoon - but residents say the intensity of the cyclone was not explained.
Town criers, who walk around the streets ringing a bell and shouting out information in the local Malagasy language, are normally used by the government in a time of crisis. But Mr Healy said they were not heard on Monday, and it has left many people taken aback by the storm's severity."
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One day I will get a car, when I can pay for insurance
Member Since: February 11, 2012 Posts: 0 Comments: 9871
Quoting MTWX:

I was just using this single tornado as an example (struck close to home). That's all it takes is one...


This could be your primer for next month. March & April always seem to be the worst in the south in regards to large violent tornadoes.
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36. MTWX
Quoting StormTracker2K:


There won't anything close to that oubreak tomorrow but an isolated tornado or two (maybe strong tornado) can't be ruled out but nothing of the magnitude of the outbreak last year atleast not yet.

I totally agree. I was just using this single tornado as an example (struck close to home). That's all it takes is one...
Member Since: July 20, 2009 Posts: 23 Comments: 1394
Quoting TampaSpin:


Brother has owned a GTO for about 10 years now....SWEET roaring ride. He wins every car show he enters her in!
Definitely one of my favorite muscle cars. They dont make them like they use to I tell ya.
Member Since: September 27, 2007 Posts: 1 Comments: 26897
Quoting MTWX:

Waiting on SPCs 1730 outlook myself... We could really do without another one of these for a while..
Link


There won't anything close to that oubreak tomorrow but an isolated tornado or two (maybe strong tornado) can't be ruled out but nothing of the magnitude of the outbreak last year atleast not yet.
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Quoting hydrus:
True. But I bought her for $750.00 in 84. Which made her look pretty good..:)


Brother has owned a GTO for about 10 years now....SWEET roaring ride. He wins every car show he enters her in!
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Quoting RitaEvac:


Best Engine, but not best looking
True. But I bought her for $750.00 in 84. Which made her look pretty good..:)
Member Since: September 27, 2007 Posts: 1 Comments: 26897
31. MTWX
Quoting GeorgiaStormz:
I know, but what i really want to see is the update this afternoon at 1630 or 1730 utc.
The rest of the WFOs do not seem to believe there will be anything overly strong

Waiting on SPCs 1730 outlook myself... We could really do without another one of these for a while..
Link
Member Since: July 20, 2009 Posts: 23 Comments: 1394
">


Gotta LOVE THIS ONE!
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Quoting RitaEvac:
Haven't heard too much complaining around NOLA, but pretty bad according to drought monitor







Drought is getting bad here in C and N FL as well but relief is on the way later this week and this weekend. S FL however may only be left with just pop up storms.

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Quoting hydrus:
This is the best car I ever owned. 1967 Cutlass Supreme. 330 Jetfire engine. 2 speed Hydroglide tranny..320 hp off the showroom floor.


Best Engine, but not best looking
Member Since: July 14, 2008 Posts: 2 Comments: 10139
Quoting RitaEvac:


Best.Car.Ever.
This is the best car I ever owned. 1967 Cutlass Supreme. 330 Jetfire engine. 2 speed Hydroglide tranny..320 hp off the showroom floor.
Member Since: September 27, 2007 Posts: 1 Comments: 26897
Has to do with Lakes, reservoirs, and other factors of the soil
Member Since: July 14, 2008 Posts: 2 Comments: 10139
Quoting RitaEvac:
Haven't heard too much complaining around NOLA, but pretty bad according to drought monitor







i think its funny how when it says that i was in a severe drought, and now i am in abnormally dry range, the effects didnt change lol.
Member Since: August 4, 2011 Posts: 46 Comments: 4537
Quoting RitaEvac:
Since everything is going to hell in a hand bag, I'm going to purchase the following and not worry about debt since uncle Sam doesn't seem to care either and enjoy the last few months....







Now thats what i'm talking about....:)
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Quoting hydrus:
What an awesome looking car...


Best.Car.Ever.
Member Since: July 14, 2008 Posts: 2 Comments: 10139
Quoting RitaEvac:
Since everything is going to hell in a hand bag, I'm going to purchase the following and not worry about debt since uncle Sam doesn't seem to care either and enjoy the last few months....




What an awesome looking car...
Member Since: September 27, 2007 Posts: 1 Comments: 26897
what exactly is that?
Member Since: February 11, 2012 Posts: 0 Comments: 9871
Since everything is going to hell in a hand bag, I'm going to purchase the following and not worry about debt since uncle Sam doesn't seem to care either and enjoy the last few months....




Member Since: July 14, 2008 Posts: 2 Comments: 10139
I know, but what i really want to see is the update this afternoon at 1630 or 1730 utc.
The rest of the WFOs do not seem to believe there will be anything overly strong
Member Since: February 11, 2012 Posts: 0 Comments: 9871
18. MTWX
Quoting GeorgiaStormz:
NWS Jackson, MS is ,as usual, the first WFO to post anything about severe t-storms.


SPC is talking even the possiblity of a strong tornado or two tomorrow too. SPC Day 2 Outlook
Member Since: July 20, 2009 Posts: 23 Comments: 1394
‎"Ride The Storm" Commercial Extended Cut - 2012 Weather Underground Mitsubishi All-Wheel Control Lineup

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NWS Jackson, MS is ,as usual, the first WFO to post anything about severe t-storms.

Member Since: February 11, 2012 Posts: 0 Comments: 9871
Quoting Neapolitan:
'Storm of the Century?' Try 'Storm of the Decade'. With climate change, today's '100-year floods' may happen every three to 20 years, according to new research.....



Nice link find NEA.. looks like the climate is fighting back!
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'Storm of the Century?' Try 'Storm of the Decade'. With climate change, today's '100-year floods' may happen every three to 20 years, according to new research.

Last August, Hurricane Irene spun through the Caribbean and parts of the eastern United States, leaving widespread wreckage in its wake. The Category 3 storm whipped up water levels, generating storm surges that swept over seawalls and flooded seaside and inland communities. Many hurricane analysts suggested, based on the wide extent of flooding, that Irene was a "100-year event": a storm that only comes around once in a century.

However, researchers from MIT and Princeton University have found that with climate change, such storms could make landfall far more frequently, causing powerful, devastating storm surges every three to 20 years. The group simulated tens of thousands of storms under different climate conditions, finding that today's "500-year floods" could, with climate change, occur once every 25 to 240 years. The researchers published their results in the current issue of
Nature Climate Change.

- - - - - - - - - -

To simulate present and future storm activity in the region, the researchers combined four climate models with a specific hurricane model. The combined models generated 45,000 synthetic storms within a 200-kilometer radius of Battery Park, at the southern tip of Manhattan.

- - - - - - - - - -

Today, a "100-year storm" means a surge flood of about two meters, on average, in New York. Roughly every 500 years, the region experiences towering, three-meter-high surge floods. Both scenarios, Lin notes, would easily top Manhattan’s seawalls, which stand 1.5 meters high.

But with added greenhouse gas emissions, the models found that a two-meter surge flood would instead occur once every three to 20 years; a three-meter flood would occur every 25 to 240 years.


Full article...
Member Since: November 8, 2009 Posts: 4 Comments: 14847
Fiji Meteorological Services
Tropical Disturbance Advisory #23
TROPICAL CYCLONE JASMINE (12F)
0:00 AM FST February 15 2012
===================================

TROPICAL CYCLONE WARNING.
A GALE WARNING REMAINS IN FORCE FOR THE TONGATAPU GROUP.
A STRONG WIND WARNING REMAINS IN FORCE FOR THE VAVA'U AND HA'APAI GROUP


At 12:00 PM UTC, Tropical Cyclone Jasmine, Category One (987 hPa) located at 21.1S 175.9W has 10 minute sustained winds of 45 knots. The cyclone is reported as moving north northwest at 6 knots. Position poor based on hourly GMS imagery and peripheral surface reports.

Gale Force Winds
==================
70 NM from the center in northeast quadrant
70 NM from the center in southeast quadrant
60 NM from the center in southwest quadrant
20 NM from the center in northwest quadrant

Overall organization remains same in past 12 hours. Convection has slightly decreased in last 6 hours. System lies just to the north of an upper ridge. Associated upper divergence and low level convergence are both moderate. Vertical shear is minimal. Sea surface temperature about 27 to 28C

Dvorak analysis based on 0.5 wrap on log10 spiral, yielding DT=2.5, PT=3.0 and MET=3.0, final Dvorak based on MET

Dvorak Intensity: T3.0/3.0/D1.0/24 HRS

Most global models agree on a west northwest movement with no further intensification.

Forecast and Intensity:
=======================

12 HRS: 20.9S 177.1W - 45 knots (CAT 1)
24 HRS: 21.4S 177.8W - 40 knots (CAT 1)
48 HRS: 23.3S 178.3W - 30 knots (Tropical Depression)

The next tropical disturbance advisory from Fiji Meteorological Services on TC JASMINE will be issued at 20:30 PM UTC..
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Haven't heard too much complaining around NOLA, but pretty bad according to drought monitor





Member Since: July 14, 2008 Posts: 2 Comments: 10139
3.38" for the first half of February at my place. More coming
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Mauritius Meteorological Services
Tropical Cyclone Advisory #1
DEPRESSION TROPICALE 10-20112012
16:00 PM RET February 14 2012
=====================================

At 12:00 PM UTC, Tropical Depression 10 (999 hPa) located at 13.9S 89.4E has 10 minute sustained winds of 30 knots with gusts of 45 knots. The depression is reported as moving west southwest at 16 knots.

Dvorak Intensity:

Forecast and Intensity
========================

12 HRS: 14.9S 85.5E - 30 knots (Depression Tropicale)
24 HRS: 15.4S 83.0E - 30 knots (Depression Tropicale)
48 HRS: 16.0S 79.1E - 25 knots (Perturbation Tropicale)
72 HRS: 16.8S 75.2E - 25 knots (Perturbation Tropicale)

Additional Information
=======================

The next tropical cyclone advisory from Mauritius Meteorological Service will be issued at 18:30 PM UTC..
Member Since: May 24, 2006 Posts: 59 Comments: 53267
Fiji Meteorological Services
Tropical Disturbance Summary
TROPICAL DEPRESSION 13F
18:00 PM FST February 14 2012
=================================

At 6:00 AM UTC, Tropical Depression 13F (1005 hPa) located at 17.3S 161.9E is reported as slow moving. Position poor based on multisatellite infrared imagery with animation and peripheral surface observations. Sea surface temperature is around 29C.

Organization has not changed much in the past 12 hours. Convection has slightly increased in the past 6 to 12 hours. Cyclonic circulation extends up to 700 HPA. Td13f lies under 250 HPA ridge axis in a low sheared environment.

Global models have yet to pick the system.

The potential for this system to develop into a tropical cyclone in the next 24-48 hours is low.
Member Since: May 24, 2006 Posts: 59 Comments: 53267
SH132012 - Tropical Cyclone (<64 kt) THIRTEEN



Enhanced Infrared (IR) Imagery (4 km Mercator)

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Seychelles Meteorological Services
Tropical Cyclone Advisory #22
DEPRESSION SUR TERRE, FORMER GIOVANNA (09-20112012)
16:00 PM RET February 14 2012
================================

At 12:00 PM UTC, Overland Depression, Former Giovanna (xxxx hPa) located at 19.3S 46.2E has 10 minute sustained winds of 25 knots with gusts of 40 knots. The cyclone is reported as moving west southwest at 10 knots.

Dvorak Intensity: OVERLAND

Forecast and Intensity
========================

12 HRS: 20.6S 43.6E - 30 knots (Depression Tropicale)
24 HRS: 21.8S 41.8E - 40 knots (Tempête Tropicale Modérée)
48 HRS: 23.1S 39.6E - 55 knots (Forte Tempête Tropicale)
72 HRS: 23.8S 37.8E - 65 knots (CYCLONE Tropical)

Additional Information
=====================

Ex-giovanna is tracking globally west southwestward on the steering influence of the deep of low to mid-troposphere centered south of Réunion Island. It is forecast to keep on this track for the next three days but should progressively slow down in the direction a barometric col transiting in the south of the Mozambique channel. It is forecast to recurve southeastward on Saturday, and speed should remain slow, due to a weak steering influence in the mid-troposphere.

Numerical weather prediction models are in good agreement for the track during the next 48 hours. Beyond the forecast tracks are spread out. Some numerical weather prediction models forecast a east to west track, towards the Mozambique coast, others like ECMWF forecast the south-eastward bending, more or less rapidly. The present forecast track of the RSMC is close to the ECMWF model. According to the last run of ECMWF, it is less rapid than the previous forecast track.

On this track, residual vortex should be back over sea in the Mozambique channel late Tuesday in the vicinity of Morondava. With a favorable atmospheric environment, a decreasing easterly shear as the system will move closer to an upper level ridge, a good low levels feeding on the both sides of the low, and warm sea surface temperature, system should regenerate rapidly over the channel. At the end of the forecast range, system should begin to undergo westerly upper level vertical wind shear and should weaken.

The next tropical cyclone advisory on TD GIOVANNA issued by Seychelles Meteorological Services will be issued at 18:30 PM UTC..
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SH122012 - Tropical Cyclone (<64 kt) GIOVANNA

Enhanced Infrared (IR) Imagery (4 km Mercator)



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Thanks Jeff...
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Thank you for the update Dr. Masters. Here is hoping the damage was not too severe. It was surprising to observe the relatively low sustained winds at the reporting stations across Madagascar as the storm made landfall. Most locations like Antananarivo didn't even quite get sustained tropical storm conditions. The core of strongest winds must have been relatively small.
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Madagascar's emergency service now says three people have died, but reports obviously aren't anywhere near complete. In fact, assessments are just underway along the coast, where there are reports of storm surge making its way several blocks inland.

Giovanna
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Thank you Dr. Masters! Happy VD!
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Dr. Masters (r) co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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