Cooperative Institute for Meteorological Satellite Studies / University of Wisconsin-Madison
Tropical Cyclones
AI Rapid Intensification Index   (Reference)

 

current Twentyone intensity image current Twentyone RI diff image

 


Twenty-One at 09/01/26 00 UTC. Intensity = 30 kts, MPI = 126 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
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RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 1.1% 0.1% 3.9% RIPA Consensus N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AI-RI in RIPA Consensus N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Linear Discriminant Analysis N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Logistic Regression N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
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Twenty-One at 08/31/26 18 UTC. Intensity = 30 kts, MPI = 132 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
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RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 4.4% RIPA Consensus N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
AI-RI in RIPA Consensus N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Linear Discriminant Analysis N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Logistic Regression N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
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Twenty-One at 08/31/26 12 UTC. Intensity = 30 kts, MPI = 127 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.0% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% RIPA Consensus 0.0% 0.5% 0.2% 0.0% 0.0% 0.2% 0.1% 3.0% 0.4% 27.0%
AI-RI in RIPA Consensus 0.0% 0.3% 0.1% 0.0% 0.0% 0.1% 0.0% 2.0% 0.2% 18.0% Linear Discriminant Analysis 0.0% 0.2% 0.2% 0.0% 0.0% 0.1% 0.1% 5.7% 0.7% 50.0%
Logistic Regression 0.1% 0.8% 0.1% 0.1% 0.1% 0.2% 0.0% 0.3% 0.1% 4.0%
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Twenty-One at 08/31/26 06 UTC. Intensity = 40 kts, MPI = 130 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.1% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% RIPA Consensus 0.8% 3.3% 1.2% 0.6% 0.5% 1.1% 0.2% 2.6% 0.3% 17.1%
AI-RI in RIPA Consensus 0.5% 2.2% 0.8% 0.4% 0.3% 0.7% 0.1% 1.7% 0.2% 11.4% Linear Discriminant Analysis 1.1% 2.0% 1.3% 0.4% 0.2% 0.6% 0.2% 4.8% 0.5% 30.7%
Logistic Regression 0.5% 4.6% 1.1% 0.8% 0.8% 1.7% 0.2% 0.3% 0.2% 3.5%
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Etau at 08/31/26 00 UTC. Intensity = 30 kts, MPI = 141 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.3% 0.7% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% RIPA Consensus 0.2% 1.6% 0.4% 0.3% 0.2% 1.2% 0.3% 2.3% 0.4% 16.6%
AI-RI in RIPA Consensus 0.2% 1.3% 0.3% 0.1% 0.1% 0.8% 0.1% 1.5% 0.2% 11.0% Linear Discriminant Analysis 0.1% 0.6% 0.2% 0.1% 0.0% 0.4% 0.2% 4.3% 0.5% 29.5%
Logistic Regression 0.3% 2.7% 0.6% 0.4% 0.4% 2.1% 0.3% 0.4% 0.2% 3.6%
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Etau at 08/30/26 18 UTC. Intensity = 30 kts, MPI = 140 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.3% 1.7% 0.4% 0.1% 0.0% 0.1% 0.1% 0.1% 0.0% 3.4% RIPA Consensus 0.4% 2.5% 0.7% 0.4% 0.3% 1.0% 0.2% 3.5% 0.6% 16.8%
AI-RI in RIPA Consensus 0.3% 2.2% 0.6% 0.3% 0.1% 0.7% 0.1% 2.3% 0.4% 12.3% Linear Discriminant Analysis 0.3% 0.9% 0.4% 0.2% 0.0% 0.3% 0.1% 6.4% 1.1% 28.6%
Logistic Regression 0.5% 4.2% 1.1% 0.7% 0.6% 1.7% 0.2% 0.5% 0.2% 5.0%
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Etau at 08/30/26 12 UTC. Intensity = 30 kts, MPI = 139 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.5% 5.5% 1.8% 0.0% 0.1% 0.1% 0.0% 3.6% 0.0% 4.6% RIPA Consensus 1.0% 5.5% 1.9% 1.0% 0.9% 4.6% 1.5% 12.2% 4.4% 18.3%
AI-RI in RIPA Consensus 0.8% 5.5% 1.8% 0.6% 0.6% 3.1% 1.0% 9.3% 2.9% 13.7% Linear Discriminant Analysis 0.8% 2.9% 1.5% 0.3% 0.1% 2.9% 1.7% 22.8% 8.1% 35.3%
Logistic Regression 1.2% 8.2% 2.4% 1.7% 1.6% 6.3% 1.3% 1.7% 0.7% 1.2%
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Etau at 08/30/26 06 UTC. Intensity = 30 kts, MPI = 139 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.4% 4.5% 0.4% 0.1% 0.0% 0.1% 0.0% 0.0% 0.0% 0.9% RIPA Consensus 0.2% 2.5% 0.7% 0.4% 0.3% 1.5% 0.3% 11.6% 3.8% 33.2%
AI-RI in RIPA Consensus 0.2% 3.1% 0.6% 0.2% 0.2% 1.0% 0.1% 7.7% 2.5% 22.4% Linear Discriminant Analysis 0.0% 0.7% 0.3% 0.0% 0.0% 0.7% 0.3% 21.8% 7.3% 62.6%
Logistic Regression 0.4% 4.3% 1.1% 0.7% 0.7% 2.3% 0.3% 1.4% 0.3% 3.8%
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Etau at 08/30/26 00 UTC. Intensity = 25 kts, MPI = 140 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.4% 4.8% 0.8% 0.1% 0.0% 0.2% 0.1% 0.1% 0.0% 0.0% RIPA Consensus 0.2% 2.8% 0.8% 0.4% 0.4% 2.9% 0.8% 15.0% 5.9% 35.2%
AI-RI in RIPA Consensus 0.3% 3.5% 0.7% 0.3% 0.2% 2.0% 0.5% 10.0% 3.9% 23.4% Linear Discriminant Analysis 0.0% 0.7% 0.2% 0.0% 0.0% 1.4% 0.8% 27.7% 11.0% 62.6%
Logistic Regression 0.5% 5.0% 1.3% 0.8% 0.7% 4.5% 0.8% 2.3% 0.7% 7.8%
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Etau at 08/29/26 18 UTC. Intensity = 35 kts, MPI = 147 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.2% 2.1% 0.2% 0.1% 0.0% 0.2% 0.1% 0.1% 0.0% 2.1% RIPA Consensus 0.6% 3.3% 1.1% 0.7% 0.5% 3.8% 1.2% 19.4% 8.9% 39.1%
AI-RI in RIPA Consensus 0.4% 2.9% 0.8% 0.5% 0.3% 2.6% 0.8% 12.9% 5.9% 26.7% Linear Discriminant Analysis 0.3% 1.3% 0.6% 0.3% 0.0% 2.7% 1.5% 34.5% 16.3% 62.6%
Logistic Regression 0.8% 5.3% 1.6% 1.1% 1.0% 4.9% 1.0% 4.3% 1.5% 15.6%
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Etau at 08/29/26 12 UTC. Intensity = 40 kts, MPI = 148 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.2% 0.2% 0.0% 0.1% 0.0% 0.5% 0.1% 0.1% 0.0% 5.2% RIPA Consensus 2.5% 19.1% 9.3% 6.3% 4.7% 18.0% 7.5% 30.2% 14.8% 38.7%
AI-RI in RIPA Consensus 1.7% 12.8% 6.2% 4.2% 3.1% 12.1% 5.0% 20.2% 9.8% 27.5% Linear Discriminant Analysis 2.2% 13.4% 7.6% 3.2% 0.9% 14.6% 8.5% 48.4% 25.1% 62.6%
Logistic Regression 2.8% 24.9% 11.1% 9.3% 8.4% 21.3% 6.5% 12.1% 4.5% 14.8%
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Etau at 08/29/26 06 UTC. Intensity = 40 kts, MPI = 148 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.7% 1.6% 0.6% 0.9% 0.0% 0.6% 0.2% 0.2% 0.0% 2.7% RIPA Consensus 1.5% 14.5% 6.6% 4.2% 3.2% 18.5% 8.1% 33.3% 16.4% 42.3%
AI-RI in RIPA Consensus 1.2% 10.2% 4.6% 3.0% 2.1% 12.5% 5.4% 22.2% 10.9% 29.0% Linear Discriminant Analysis 1.5% 10.1% 5.6% 2.1% 0.8% 15.0% 9.3% 49.5% 25.6% 62.6%
Logistic Regression 1.5% 19.0% 7.6% 6.2% 5.5% 21.9% 6.9% 17.1% 7.3% 21.9%
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Etau at 08/29/26 00 UTC. Intensity = 35 kts, MPI = 145 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.1% 0.5% 0.3% 0.0% 0.0% 0.2% 0.0% 0.2% 0.0% 0.3% RIPA Consensus 0.1% 2.7% 0.8% 0.4% 0.3% 3.8% 1.0% 23.8% 12.1% 36.4%
AI-RI in RIPA Consensus 0.1% 1.9% 0.6% 0.2% 0.2% 2.6% 0.6% 15.9% 8.0% 24.3% Linear Discriminant Analysis 0.0% 1.0% 0.4% 0.1% 0.0% 3.3% 1.3% 43.7% 23.2% 62.6%
Logistic Regression 0.2% 4.3% 1.1% 0.7% 0.7% 4.3% 0.7% 4.0% 1.0% 10.2%
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Etau at 08/28/26 18 UTC. Intensity = 45 kts, MPI = 144 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.1% 0.1% 0.0% 0.0% 0.0% 0.1% 0.0% 0.1% 0.0% 0.0% RIPA Consensus 1.5% 11.0% 4.6% 2.9% 2.1% 11.8% 4.0% 27.7% 13.7% 34.4%
AI-RI in RIPA Consensus 1.0% 7.3% 3.1% 1.9% 1.3% 7.8% 2.6% 18.4% 9.1% 22.9% Linear Discriminant Analysis 1.7% 8.6% 4.5% 1.8% 0.6% 11.2% 5.0% 44.3% 24.0% 57.6%
Logistic Regression 1.3% 13.4% 4.8% 4.0% 3.5% 12.4% 3.0% 11.0% 3.4% 11.2%
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Etau at 08/28/26 12 UTC. Intensity = 45 kts, MPI = 141 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 0.1% 0.1% 0.0% 0.0% 0.0% 0.3% 0.0% 0.1% 0.0% 0.1% RIPA Consensus 0.6% 2.9% 0.9% 0.5% 0.3% 3.6% 0.9% 16.0% 6.0% 26.4%
AI-RI in RIPA Consensus 0.4% 1.9% 0.6% 0.3% 0.2% 2.4% 0.6% 10.7% 4.0% 17.5% Linear Discriminant Analysis 0.8% 2.0% 1.0% 0.3% 0.1% 3.6% 1.2% 28.4% 11.1% 47.8%
Logistic Regression 0.4% 3.7% 0.9% 0.7% 0.6% 3.5% 0.6% 3.6% 0.9% 4.9%
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Etau at 08/27/26 12 UTC. Intensity = 40 kts, MPI = 138 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
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RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 3.5% 6.3% 3.3% 6.0% 0.6% 3.5% 3.0% 0.6% 0.4% 0.6% RIPA Consensus 3.4% 17.5% 7.1% 4.6% 3.3% 8.5% 2.3% 10.4% 3.2% 26.8%
AI-RI in RIPA Consensus 3.4% 13.7% 5.8% 5.1% 2.4% 6.8% 2.5% 7.1% 2.2% 18.1% Linear Discriminant Analysis 3.6% 15.2% 6.9% 2.6% 1.1% 6.4% 2.2% 17.5% 5.2% 43.1%
Logistic Regression 3.2% 19.7% 7.4% 6.7% 5.5% 10.6% 2.5% 3.3% 1.2% 10.6%
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Twentyone at 08/27/26 06 UTC. Intensity = 40 kts, MPI = 137 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
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RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 5.3% 27.5% 11.1% 5.7% 1.5% 6.0% 6.0% 1.5% 0.4% 1.1% RIPA Consensus 5.6% 19.9% 9.2% 5.3% 4.5% 10.7% 3.4% 15.1% 5.5% 17.9%
AI-RI in RIPA Consensus 5.4% 22.4% 9.8% 5.4% 3.5% 9.1% 4.3% 10.6% 3.8% 12.2% Linear Discriminant Analysis 7.2% 18.6% 10.9% 3.8% 2.3% 9.4% 4.0% 26.8% 9.5% 30.5%
Logistic Regression 3.9% 21.3% 7.6% 6.8% 6.7% 11.9% 2.9% 3.5% 1.5% 5.2%
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Twentyone at 08/27/26 00 UTC. Intensity = 30 kts, MPI = 140 kts    

 

AI-RI Matrix of RI probabilities RIPA Matrix of RI probabilities
------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------
RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72 RI (kt / h) 20/12 25/24 30/24 35/24 40/24 45/36 55/36 55/48 70/48 65/72
AI-RI 4.7% 9.1% 3.5% 5.7% 1.8% 9.0% 5.5% 2.3% 1.0% 1.3% RIPA Consensus 3.4% 25.3% 10.7% 7.6% 5.4% 15.6% 5.4% 18.9% 8.2% 25.9%
AI-RI in RIPA Consensus 3.8% 19.9% 8.3% 7.0% 4.1% 13.4% 5.4% 13.3% 5.7% 17.7% Linear Discriminant Analysis 2.5% 19.6% 8.1% 3.0% 0.9% 8.3% 3.5% 30.4% 12.2% 40.1%
Logistic Regression 4.3% 31.1% 13.4% 12.3% 9.8% 22.9% 7.3% 7.3% 4.1% 11.7%
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