Category 4 Giovanna battering Madagascar

By: Dr. Jeff Masters , 2:45 PM GMT on February 13, 2012

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Earth's most dangerous storm of 2012 is Tropical Cyclone Giovanna, which is bearing down on Madagascar as a powerful Category 4 storm with 145 mph winds. Giovanna is predicted to hit a heavily populated portion of the east coast of the island near 22 GMT tonight as a Category 3 storm, then move inland, passing near the capital of Antananarivo as a Category 1 storm on Tuesday morning. The outer spiral bands of the storm have already moved over the island, bringing heavy rains and gusty winds.


Figure 1. Visible image from NASA's Terra satellite of Tropical Cyclone Giovanna approaching Madagascar, taken at 6:35 UTC Monday February 13, 2012. At the time, Giovanna was a Category 4 storm with 145 mph winds. Image credit: NASA.


Figure 2. Webcam view of the skies over the Andila Beach Hotel in northwest Madagascar, taken at 6:15pm local time on Monday February 13, 2012. Image credit: Andilana Beach Hotel.

The forecast: not good
Recent microwave satellite imagery (Figure 3) shows that Giovanna has concentric eyewalls, and it likely that the inner eyewall will collapse today as the storm undergoes an eyewall replacement cycle. This process should gradually weaken the storm, and I expect Giovanna will weaken slightly to a still very dangerous Category 3 storm with 125 - 130 mph winds at landfall. However, the eyewall replacement cycle will spread out the storm's hurricane-force winds over a larger area, increasing the storm surge. A 70-mile long swath of the coast that is heavily populated will receive sustained hurricane-force winds tonight. Rainfall amounts in excess of eight inches in a 24-hour period are expected along the center of Giovanna's path. These rains will cause extensive flooding and major damage to the country, and the storm is likely to be one of the top three most expensive disasters in Malagasy history. The damage potential is higher than for previous storms of similar intensity, due to the considerable deforestation Madagascar has experienced over the past 30 years. Madagascar lost 8.3% of its forest cover between 1990 and 2010 and is now just 22% forested, according to mongabay.com. Flood waters run off quicker from deforested land, reach higher heights, and cause greater damage.


Figure 3. Microwave satellite image of Tropical Cyclone Giovanna taken at 12:30 UTC (7:30 am EST) Monday, February 13, 2012. The echo-free eye is surrounded by two concentric eyewalls, the sign of a storm undergoing an eyewall replacement cycle. Image credit: Navy Research Lab, Monterrey.

Madagascar's tropical cyclone history
The strongest and deadliest tropical cyclone ever recorded in Madagascar was Tropical Cyclone Gafilo, which hit the northern end of the island on March 7, 2004, as a Category 5 storm with 160 mph winds. Galfilo dumped up to 20 inches of rain on the island, and its winds and flooding rains killed 363 people and did $250 million in damage, making it the deadliest and second most expensive storm in Madagascar's history. Gafilo's central pressure of 895 mb made it the second strongest tropical cyclone ever recorded in the Southern Hemisphere, behind the 890 mb central pressure of Tropical Cyclone Zoe of December 2002, which affected Fiji and the Solomon Islands. With a central pressure of 937 mb, Giovanna is a much less intense storm than Gafilo was.

Jeff Masters

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"Ride The Storm" Commercial Extended Cut - 2012 Weather Underground Mitsubishi All-Wheel Control Lineup

Member Since: July 3, 2005 Posts: 414 Comments: 125569
So what about this 99S? Where is it supposed to go and how strong is it supposed to get?
Member Since: July 6, 2010 Posts: 108 Comments: 30251
Good night everyone!
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The Flood Advisory for NorthCentral PR was extended until Midnight AST.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
952 PM AST MON FEB 13 2012

PRC047-101-105-143-140400-
/O.EXT.TJSJ.FA.Y.0003.000000T0000Z-120214T0400Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
COROZAL PR-MOROVIS PR-NARANJITO PR-VEGA ALTA PR-
952 PM AST MON FEB 13 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS EXTENDED THE

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
COROZAL...MOROVIS...NARANJITO AND VEGA ALTA

* UNTIL MIDNIGHT AST

WEATHER DOPPLER RADAR CONTINUES TO INDICATE MODERATE SHOWER ACTIVITY
ACROSS PARTS OF THE WARNED AREA. THIS RAINFALL IN ADDITION TO THE
RAINFALL THAT HAS ALREADY OCCURRED...WILL CONTINUE TO RESULT IN
RAPID RISES ON SMALL STREAMS AND CREEKS THROUGH AT LEAST MIDNIGHT
AST.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1837 6630 1831 6625 1825 6636 1828 6638
1827 6640 1833 6645 1835 6639 1835 6638
1836 6637 1837 6632

$$

OMS
Member Since: April 29, 2009 Posts: 75 Comments: 13288
0130Z




JAVA Movie
Member Since: July 3, 2005 Posts: 414 Comments: 125569
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330. Skyepony (Mod)
TRMM caught 99S.
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Here is invest 99S,the next concern for Madagascar? First visible shows is organizing at a good rate.

Member Since: April 29, 2009 Posts: 75 Comments: 13288
327. Skyepony (Mod)
Weakening now down to 95kts.
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326. Skyepony (Mod)
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325. HadesGodWyvern (Mod)
Fiji Meteorological Services
Tropical Disturbance Advisory #21
TROPICAL CYCLONE JASMINE (12F)
12:00 PM FST February 14 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 0:00 AM UTC, Tropical Cyclone Jasmine, Category One (993 hPa) located at 21.1S 176.4W has 10 minute sustained winds of 35 knots. The cyclone is reported as moving north northwest at 5 knots. Position poor based on hourly GMS imagery and peripheral surface reports.

Gale Force Winds
==================
80 NM from the center in northeast quadrant
60 NM from the center in southeast quadrant
40 NM from the center in southwest quadrant
80 NM from the center in northwest quadrant

Overall organization has not changed much in past 24 hours. Convection has slightly increased in past 6 hours. CIMMS analysis indicate the system lies under an upper ridge axis and in low sheared environment. The system is being steered by southeasterly deep layer mean flow.Sea surface temperature around 28C.

Dvorak analysis based on 0.4 wrap on log10 spiral, yielding DT=2.5, PT=2.5 and MET=3.0, final Dvorak based on MET.

Dvorak Intensity: T2.5/3.0/S0.0/24 HRS

Most global models initially agree on the northwest track before recurving it southwestwards within 24 hours.

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

12 HRS: 20.8S 176.7W - 35 knots (CAT 1)
24 HRS: 21.0S 177.3W - 35 knots (CAT 1)
48 HRS: 22.5S 178.1W - 35 knots (CAT 1)

The next tropical disturbance advisory from Fiji Meteorological Services on TC JASMINE will be issued at 8:30 AM UTC..
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Quoting HadesGodWyvern:
A bit of uncertainty in the future track
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323. HadesGodWyvern (Mod)
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Link
Member Since: August 4, 2011 Posts: 46 Comments: 4481
Quoting SPLbeater:


maybe a strong tropical cyclone. may not have time to get to cyclone strength again.


It has days out over the warm enough waters of the Mozambique channel.
Member Since: November 19, 2010 Posts: 1 Comments: 1285
320. HadesGodWyvern (Mod)
Quoting MAweatherboy1:
How much are we thinking Giovanna restrengthens when it gets over the Mozambique Channel?


RSMC has it up to 80 knots (1 min) potential as in the Mozambique Channel

2.B LONGER-RANGE OUTLOOK :
96H: 2012/02/18 00 UTC: 26.1 S / 36.7 E, MAX WIND=070 KT, TROPICAL CYCLONE
120H: 2012/02/19 00 UTC: 26.4 S / 37.9 E, MAX WIND=065 KT, TROPICAL CYCLONE
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Quoting MAweatherboy1:
How much are we thinking Giovanna restrengthens when it gets over the Mozambique Channel?
The further north it stays the warmer the SST's
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Quoting MAweatherboy1:
How much are we thinking Giovanna restrengthens when it gets over the Mozambique Channel?


maybe a strong tropical cyclone. may not have time to get to cyclone strength again.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
How much are we thinking Giovanna restrengthens when it gets over the Mozambique Channel?
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The PNA is forecast to go negative soon...warmer pattern for the E CONUS if this verifies.

Also, the NAO is currently in the negative range, but will be back positive by the 15th. Maybe I dont got to put up with this cold weather much longer...lol.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
314. HadesGodWyvern (Mod)
Seychelles Meteorological Services
Tropical Cyclone Advisory #20
DEPRESSION SUR TERRE, FORMER GIOVANNA (09-20112012)
4:00 AM RET February 14 2012
================================

At 0:00 AM UTC, Overland Depression, Former Giovanna (945 hPa) located at 19.0S 48.8E has 10 minute sustained winds of 90 knots with gusts of 130 knots. The cyclone is reported as moving west at 12 knots.

Hurricane Force Winds
========================
50 NM radius from the center in eastern semi-circle

Storm Force Winds
=================
85 NM radius from the center in the eastern semi-circle

Gale Force Winds
=================
120 NM radius from the center in the eastern semi-circle

Near Gale Force Winds
=====================
160 NM radius from the center in the eastern semi-circle

Dvorak Intensity: OVERLAND

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

12 HRS: 20.4S 45.3E - 25 knots (Depression sur Terre)
24 HRS: 21.4S 42.8E - 30 knots (Depression Tropicale)
48 HRS: 23.8S 39.3E - 50 knots (Forte Tempête Tropicale)
72 HRS: 24.8S 37.9E - 60 knots (Forte Tempête Tropicale)

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

Giovanna has made landfall near Andovoranto Monday at about 2200 PM UTC. Gusts has probably exceed 120 km/h in an area from Nosy-Varika in the south to Sainte-Marie island in the north, 150 km/h from Mahanoro in the south to Toamasina in the north and 200 km/h from Vaomandry in the south up to 50 km in the north of Andovoranto.

Coastal flooding have probably occurred in the south of the landfall up to 50 km south of Andovoranto in relationship with the combined effect of a storm surge estimated at 2.5 to 3.0 meters and a more than 12 meter high cyclonic swell. This area has probably undergo within the same time gusts from 200 to 250 km/h

Giovanna should be back over sea in the Mozambique Channel late Tuesday or early Wednesday within a favorable atmospheric environment with a decreasing easterly shear as the system will move closer to an upper level ridge. Latest ECMWF run suggests a rapid re-intensification that is reflected by the official RSMC forecast. On and after84 hours system is expected to recurve southwards then southeastwards towards a mid-latitudes trough transiting in its south.

The next tropical cyclone advisory on TC GIOVANNA issued by Seychelles Meteorological Services will be issued at 6:30 AM UTC..
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Quoting washingtonian115:
Do you live in the D.C area?.Or as referred to the D.M.V?


yes in springfield!! obvisouly you do, what part are you in?
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Quoting uncwhurricane85:


i know its not hurricane season!!!! el nino or la nino hurricanes happen in both!!! and very often in both.... lets turn the attention to this late weeks possible mid atlantic snow storm!!!
Do you live in the D.C area?.Or as referred to the D.M.V?
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it feels so good to have a full stomach.


I know...its not current becuz Giovanna made landfall...but still COOL.

And we got both this time too.
Member Since: August 4, 2011 Posts: 46 Comments: 4481
The Cyclones core is fully inland now..as the impact has been under way proper for the last 5 hours easily.
Member Since: July 3, 2005 Posts: 414 Comments: 125569
Quoting Skyepony:
Looking at MIMIC, Giovanna is maintaining strength at ~125kts as it's lining up for a landfall somewhere around 19S.

I hope Madagascar fares well. A mountainous, densely populated island about to get hit by a Category 4 cyclone is never good...
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Typhoon 12S

UW-CIMSS Automated Satellite-Based
Advanced Dvorak Technique (ADT)
Version 8.1.3
Tropical Cyclone Intensity Estimation Algorithm


Current Intensity Analysis



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 14 FEB 2012 Time : 000000 UTC
Lat : 18:57:00 S Lon : 48:13:26 E


TROPICAL CYCLONE OVER LAND
NO ADT ANALYSIS AVAILABLE


************************************************* ***



Member Since: July 3, 2005 Posts: 414 Comments: 125569
Quoting washingtonian115:
The closer the band of warm water is to South America the less storms we see in the Atlantic.The further it is away from South America the more storms we get in the Atlantic.It all makes since.09 and 97 both had warm water bundled up at the S.A coast unlike 04...
very interesting, as it suggest that el ninos can indeed produce very active hurricane season and there must be some similar anomolies with la nina as well.
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Quoting aspectre:
Hokay. Anybody know the coordinates of Giovanna's landfall? it's current position?

That's your job. Use your mappy thing. :P
Member Since: July 6, 2010 Posts: 108 Comments: 30251
Member Since: July 3, 2005 Posts: 414 Comments: 125569
Quoting aspectre:
Hokay. Anybody know the coordinates of Giovanna's landfall? it's current position?


Isn't that your forte? ;)
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Hokay. Anybody know the coordinates of Giovanna's landfall? it's current position?
Member Since: August 21, 2007 Posts: 0 Comments: 4860
302. Skyepony (Mod)
Looking at MIMIC, Giovanna is maintaining strength at ~125kts as it's lining up for a landfall somewhere around 19S.
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Quoting washingtonian115:
Geez I would love it if people return the favor of plusing my comments...


i know its not hurricane season!!!! el nino or la nino hurricanes happen in both!!! and very often in both.... lets turn the attention to this late weeks possible mid atlantic snow storm!!!
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Member Since: July 3, 2005 Posts: 414 Comments: 125569
0000Z Image SH122012 - Tropical Cyclone (>64 kt) GIOVANNA

Enhanced Infrared (IR) Imagery (4 km Mercator)


Member Since: July 3, 2005 Posts: 414 Comments: 125569
Quoting nigel20:
2004 was a very strange huricane, infact 2004 was an hyperactive huricane season...which is rather strange for an el nino year.
The El-Nino of 2004 was at its end throughout the hurricane season. Which may have contributed weird season and probably the worst year of my entire life.
Member Since: September 27, 2007 Posts: 1 Comments: 19518
Quoting washingtonian115:
Geez I would love it if people return the favor of plusing my comments...

You're welcome. :P
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Quoting KoritheMan:


The largest period I could find without an El Nino was from 1958-1962. So it's not as if multiple years without an El Nino are unprecedented.
Look who came out to play.....
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Look at that very warm pool of water creeping eastward,already surpassing the 160W longitud.

Member Since: April 29, 2009 Posts: 75 Comments: 13288
Quoting Tropicsweatherpr:


Not a drop so far in Santurce,but we have a flood advisory for NorthCentral PR.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
802 PM AST MON FEB 13 2012

PRC047-101-105-143-140200-
/O.NEW.TJSJ.FA.Y.0003.120214T0002Z-120214T0200Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
COROZAL PR-MOROVIS PR-NARANJITO PR-VEGA ALTA PR-
802 PM AST MON FEB 13 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
COROZAL...MOROVIS...NARANJITO AND VEGA ALTA

* UNTIL 1000 PM AST

* AT 759 PM AST...DOPPLER RADAR INDICATED NUMEROUS SHOWERS IN THE
ADVISORY AREA. THESE AREAS OF SHOWERS HAVE THE CAPABILITY OF
PRODUCING MODERATE TO LOCALLY HEAVY RAINFALL WHICH WILL LEAD TO
RAPID RISES ON SMALL STREAMS AND CREEKS...AS WELL AS MINOR FLOODING
ALONG ROADWAYS...THROUGH AT LEAST 10:00PM AST.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1837 6630 1831 6625 1825 6636 1828 6638
1827 6640 1833 6645 1835 6639 1835 6638
1836 6637 1837 6632

$$

OMS

A steady rain all afternoon and evening here. Still drizzling. I'm worried about the Cibuco River overflowing.
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Quoting TropicalAnalystwx13:

I wonder if we'll see an El Nino anytime soon. I don't think so.


The largest period I could find without an El Nino was from 1958-1962. So it's not as if multiple years without an El Nino are unprecedented.
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Geez I would love it if people return the favor of plusing my comments...
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Quoting TropicalAnalystwx13:

Post #281.

"A new paper published in Science last Friday attempts to explain why some El Ni�o years see high Atlantic hurricane activity. "Impact of Shifting Patterns of Pacific Ocean Warming on North Atlantic Tropical Cyclones", by Georgia Tech researchers Hye-Mi Kim, Peter Webster, and Judith Curry, theorizes that Atlantic hurricane activity is sensitive to exactly where in the Pacific Ocean El Ni�o warming occurs. If the warming occurs primarily in the Eastern Pacific, near the coast of South America, the resulting atmospheric circulation pattern creates very high wind shear over the tropical Atlantic, resulting in fewer hurricanes. This pattern, called the Eastern Pacific Warming (EPW) pattern, occurred most recently during the El Ni�o years of 1997, 1987, and 1982 (Figure 1). In contrast, more warming occurred in the Central Pacific during the El Ni�o years of 2004, 2002, 1994, and 1991. The scientists showed that these Central Pacific Warming (CPW) years had lower wind shear over the Atlantic, and thus featured higher hurricane activity than is typical for an El Ni�o year. One of the paper's authors, Professor Peter J. Webster, said the variant Central Pacific Warming (CPW) El Ni�o pattern was discovered in the 1980s by Japanese and Korean researchers, who dubbed it modiki El Ni�o. Modiki is the Japanese word for "similar, but different"."

The closer the band of warm water is to South America the less storms we see in the Atlantic.The further it is away from South America the more storms we get in the Atlantic.It all makes since.09 and 97 both had warm water bundled up at the S.A coast unlike 04...
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Quoting WeatherNerdPR:

It mostly rains in isolated mountain areas. First time in a while we've gotten generalized rains like this.


Not a drop so far in Santurce,but we have a flood advisory for NorthCentral PR.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
802 PM AST MON FEB 13 2012

PRC047-101-105-143-140200-
/O.NEW.TJSJ.FA.Y.0003.120214T0002Z-120214T0200Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
COROZAL PR-MOROVIS PR-NARANJITO PR-VEGA ALTA PR-
802 PM AST MON FEB 13 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
COROZAL...MOROVIS...NARANJITO AND VEGA ALTA

* UNTIL 1000 PM AST

* AT 759 PM AST...DOPPLER RADAR INDICATED NUMEROUS SHOWERS IN THE
ADVISORY AREA. THESE AREAS OF SHOWERS HAVE THE CAPABILITY OF
PRODUCING MODERATE TO LOCALLY HEAVY RAINFALL WHICH WILL LEAD TO
RAPID RISES ON SMALL STREAMS AND CREEKS...AS WELL AS MINOR FLOODING
ALONG ROADWAYS...THROUGH AT LEAST 10:00PM AST.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1837 6630 1831 6625 1825 6636 1828 6638
1827 6640 1833 6645 1835 6639 1835 6638
1836 6637 1837 6632

$$

OMS
Member Since: April 29, 2009 Posts: 75 Comments: 13288
Quoting MAweatherboy1:

Serious question: Is it ever not raining in Puerto Rico?

It mostly rains in isolated mountain areas. First time in a while we've gotten generalized rains like this.
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Quoting TropicalAnalystwx13:

Post #281.
yeah...I saw it after I posted the question
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Quoting TropicalAnalystwx13:
...and now for our daily view of the Puerto Rican radar site showing rainfall...

:P
It hasn't stopped raining since 4:30. 4.8" so far. All of this falling into a river that passes through my town. Tomorrow's morning commute isn't going to be pretty.
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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.