Hurricane Teddy (Category One) Could Pose A Long-Range Threat To The Region

 

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WTNT35 KNHC 170243

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BULLETIN

Hurricane Teddy Advisory Number  19

NWS National Hurricane Center Miami FL       AL202020

1100 PM AST Wed Sep 16 2020

...TEDDY FORECAST TO STRENGTHEN OVER THE NEXT COUPLE OF DAYS...

SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION

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LOCATION...17.8N 51.5W

ABOUT 670 MI...1075 KM ENE OF THE LESSER ANTILLES

MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H

PRESENT MOVEMENT...NW OR 315 DEGREES AT 13 MPH...20 KM/H

MINIMUM CENTRAL PRESSURE...976 MB...28.82 INCHES

WATCHES AND WARNINGS

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There are no coastal watches or warnings in effect.

DISCUSSION AND OUTLOOK

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At 1100 PM AST (0300 UTC), the center of Hurricane Teddy was located

near latitude 17.8 North, longitude 51.5 West.  Teddy is moving

toward the northwest near 13 mph (20 km/h), and this general motion 

is expected to continue through the weekend.

Maximum sustained winds are near 90 mph (150 km/h) with higher

gusts.  Strengthening is forecast during the next couple of days, 

and Teddy could become a major hurricane Thursday night or Friday.

Hurricane-force winds extend outward up to 35 miles (55 km) from the

center and tropical-storm-force winds extend outward up to 255 miles

(405 km).

The estimated minimum central pressure is 976 mb (28.82 inches).

HAZARDS AFFECTING LAND

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SURF:  Large swells generated by Teddy are reaching the Lesser

Antilles and the northeastern coast of South America and should

spread westward to the Greater Antilles, the Bahamas, Bermuda, and

the east coast of the United States by the weekend.  These

swells are likely to cause life-threatening surf and rip current

conditions.  Please consult products from your local weather office.

NEXT ADVISORY

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Next complete advisory at 500 AM AST.

$$

Forecaster Berg

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Hurricane Teddy Discussion Number  19

NWS National Hurricane Center Miami FL       AL202020

1100 PM AST Wed Sep 16 2020

Teddy has been a perplexing hurricane thus far.  The infrared 

satellite presentation appears rather impressive, with the center 

embedded beneath a Central Dense Overcast with cloud tops as cold 

as -85 degrees Celsius.  Despite the presentation, however, Dvorak 

estimates from TAFB and SAB are a consensus T4.5/77 kt, and 

objective estimates range between 70-75 kt.  Teddy's initial 

intensity is therefore set just above these estimates at 80 kt.

A recent ASCAT pass indicated that Teddy's center is a little 

farther to the southwest than previously estimated.  However, the 

long-term motion remains toward the northwest (315/11 kt).  The 

track forecast remains straightforward the the next 3 days, with 

the guidance in good agreement that a mid-tropospheric high over 

the central Atlantic will drive the hurricane northwestward toward 

the western Atlantic.  There is a little more spread among the 

track models on days 4 and 5, related to timing differences on 

exactly where and how fast Teddy begins to recurve ahead of an 

approaching mid-latitude trough coming from the northeastern United 

States.  The new NHC track forecast has been nudged westward during 

the first 3 days to account for the initial position adjustment, 

but otherwise it's still close to the previous prediction even with 

the increasing model spread on days 4 and 5.

An upper-level trough situated to the northwest of Teddy is causing 

about 10-15 kt of deep-layer southwesterly shear over the 

hurricane, and some model analyses suggest that there could be 

stronger shear in a layer below the level of the upper-level 

outflow.  The deep-layer shear is expected to increase a bit during 

the next day or so, but this should be offset by a favorable 

thermodynamic environment, allowing for some intensification during 

that time.  The shear might relax by days 3 and 4, but then the 

thermodynamic environment becomes a little less conducive for 

strengthening.  In particular, Teddy may move over the cold wake 

of Hurricane Paulette, and the SHIPS guidance indicates that 

relatively warm upper-level temperatures could be a negative 

factor.  All that said, the NHC intensity forecast lies near the 

top end of the guidance envelope, showing Teddy peaking in 

intensity in a couple of days and then only gradually weakening 

through the end of the forecast period.

FORECAST POSITIONS AND MAX WINDS

INIT  17/0300Z 17.8N  51.5W   80 KT  90 MPH

 12H  17/1200Z 18.9N  52.6W   85 KT 100 MPH

 24H  18/0000Z 20.3N  54.1W   95 KT 110 MPH

 36H  18/1200Z 21.8N  55.6W  100 KT 115 MPH

 48H  19/0000Z 23.5N  57.1W  100 KT 115 MPH

 60H  19/1200Z 25.3N  59.1W   95 KT 110 MPH

 72H  20/0000Z 27.0N  61.1W   95 KT 110 MPH

 96H  21/0000Z 30.0N  64.0W   90 KT 105 MPH

120H  22/0000Z 35.0N  64.0W   90 KT 105 MPH

$$

Forecaster Berg