Como comentábamos ayer en Seguimiento General, nueva liebre en el atlántico.



1. A NON-TROPICAL LOW PRESSURE SYSTEM LOCATED ABOUT 400 MILES
SOUTHWEST OF BERMUDA CONTINUES TO PRODUCE GALE-FORCE WINDS OVER
A LARGE PORTION OF THE WEST-CENTRAL ATLANTIC. THUNDERSTORM ACTIVITY
HAS DEVELOPED CLOSER TO THE SURFACE CENTER DURING THE PAST SEVERAL
HOURS...AND IF THIS TREND CONTINUES...THE LOW COULD GRADUALLY
ACQUIRE SUBTROPICAL CHARACTERISTICS OVER THE NEXT COUPLE OF DAYS.
THIS SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING A
SUBTROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT DRIFTS SLOWLY
WESTWARD TODAY AND NORTHWESTWARD ON TUESDAY. ADDITIONAL INFORMATION
ON THIS GALE AREA CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE
NOAA NATIONAL WEATHER SERVICE UNDER AWIPS HEADER NFDHSFAT1...AND
UNDER WMO HEADER FZNT01 KWBC.

Diagrama de fase del sistema



Y tal vez el aire seco....pero sobre todo la cizalladura sean los 2 factores más inhibidores para el próspero desarrollo del sistema a corto plazo.



Me encantan estos bichejos

SEAN, is that you?

1. A NON-TROPICAL LOW PRESSURE SYSTEM LOCATED ABOUT 400 MILES
SOUTHWEST OF BERMUDA IS PRODUCING GALE FORCE WINDS OVER AN AREA
EXTENDING SEVERAL HUNDRED MILES TO THE NORTH OF THE CENTER.  THE
ASSOCIATED SHOWERS AND THUNDERSTORMS HAVE BECOME A LITTLE BETTER
ORGANIZED OVERNIGHT...AND THE LOW COULD ACQUIRE SUBTROPICAL
CHARACTERISTICS OVER THE NEXT DAY OR TWO.  THIS SYSTEM HAS A MEDIUM
CHANCE...40 PERCENT...OF BECOMING A SUBTROPICAL CYCLONE DURING THE
NEXT 48 HOURS AS IT MOVES SLOWLY WESTWARD TODAY AND NORTHWESTWARD
ON TUESDAY.  ADDITIONAL INFORMATION ON THIS GALE AREA CAN BE FOUND
IN HIGH SEAS FORECASTS ISSUED BY THE NOAA NATIONAL WEATHER SERVICE
UNDER AWIPS HEADER NFDHSFAT1...AND UNDER WMO HEADER FZNT01 KWBC.





Buen estreno he tenido

Sean cada vez mas cerca. Segùn NHC, 60%

1. A NON-TROPICAL LOW PRESSURE SYSTEM LOCATED ABOUT 425 MILES
SOUTHWEST OF BERMUDA CONTINUES TO PRODUCE GALE FORCE WINDS OVER AN
AREA EXTENDING SEVERAL HUNDRED MILES TO THE NORTH OF THE CENTER.
THE ASSOCIATED SHOWERS AND THUNDERSTORMS CONTINUE TO SHOW SIGNS OF
ORGANIZATION...AND THE LOW COULD ACQUIRE SUBTROPICAL
CHARACTERISTICS TONIGHT OR ON TUESDAY.  THIS SYSTEM HAS A HIGH
CHANCE...60 PERCENT...OF BECOMING A SUBTROPICAL CYCLONE DURING THE
NEXT 48 HOURS AS IT MOVES SLOWLY WESTWARD TODAY AND NORTHWESTWARD
ON TUESDAY.  ADDITIONAL INFORMATION ON THIS GALE AREA CAN BE FOUND
IN HIGH SEAS FORECASTS ISSUED BY THE NOAA NATIONAL WEATHER SERVICE
UNDER AWIPS HEADER NFDHSFAT1...AND UNDER WMO HEADER FZNT01 KWBC.

Posee buen aspecto, como mantenga la convección 8-10 horas màs, probablemente tendremos Tormenta Subtropical.

Sube hasta el 70% las posibilidades del 98L. 
Lanzada la alerta de formación tropical (ó subtropical) por la Marina.

"SEAN" a la vuelta de la esquina. Mejora la circulación, se define mejor su centro y se concentra la convección alrededor de él. Último parte del NHC:
000
ACCA62 TJSJ 080549
TWOSPN

PERSPECTIVA SOBRE LAS CONDICIONES DEL TIEMPO EN EL TROPICO
NWS CENTRO NACIONAL DE HURACANES MIAMI (FLORIDA)
TRADUCCION EMITIDA POR SERVICIO NACIONAL DE METEOROLOGIA SAN JUAN PUERTO RICO
100 AM MARTES 8 DE NOVIEMBRE DE 2011

PARA EL ATLANTICO NORTE...EL MAR CARIBE Y EL GOLFO DE MEXICO...

UN SISTEMA NO TROPICAL DE BAJA PRESION LOCALIZADO COMO A 460 MILLAS
AL SUROESTE DE BERMUDA ESTA PRODUCIENDO VIENTOS CON FUERZA DE GALERNA
SOBRE UN AREA EXTENDIENDOSE VARIOS CIENTOS DE MILLAS AL OESTE HASTA
EL NORESTE DEL CENTRO. INFORMACION RECIENTE DEL SATELITE INDICA QUE
LA CIRCULACION EN LOS NIVELES BAJOS SE HA TORNADO MEJOR DEFINIDA Y
QUE LOS VIENTOS CON FUERZA DE GALERNA SE HAN DESARROLLADO CERCA AL
CENTRO EN LA SUPERFICIE. ADEMAS...LA ACTIVIDAD DE AGUACEROS HA
AUMENTADO Y SE HA TORNADO MEJOR ORGANIZADA DURANTE LAS HORAS PASADAS
Y SI ESTA TENDENCIA CONTINUA...PUDIERAN INICIARSE LAS ADVERTENCIAS
SOBRE ESTA AREA DE BAJA PRESION MAS TARDE ESTA MANANA. ESTE SISTEMA
TIENE UNA PROBABILIDAD ALTA...80 POR CIENTO...DE CONVERTIRSE EN UN
CICLON SUBTROPICAL DURANTE LAS PROXIMAS 48 HORAS MIENTRAS SE MUEVE
LENTAMENTE HACIA EL OESTE HOY. INFORMACION ADICIONAL SOBRE ESTA AREA
CON VIENTOS DE GALERNA PUEDE ENCONTRARSE EN LOS PRONOSTICOS DE ALTA
MAR EMITIDOS POR EL SERVICIO NACIONAL DE METEOROLOGIA BAJO EL TITULO
DE AWIPS NFDHSFAT1...Y BAJO EL TITULO WMO FZNT01 KWBC.

EN EL RESTO DEL AREA...NO SE ESPERA FORMACION DE CICLON TROPICAL
DURANTE LAS PROXIMAS 48 HORAS.

$$

PRONOSTICADOR BRENNAN

Stewart ha hablado.....
SEAN ya está entre nosotros

SATELLITE INFORMATION AND SURFACE OBSERVATIONS INDICATE THE LARGE
NON-TROPICAL LOW PRESSURE SYSTEM THAT HAS BEEN MEANDERING BETWEEN
BERMUDA AND THE BAHAMAS THE PAST FEW DAYS HAS ACQUIRED ENOUGH
ORGANIZED TO BE CLASSIFIED AS SUBTROPICAL STORM SEAN.

Posee 40kts, parece que no le va a dar tiempo a organizarse y alcanzar la categoria de tropical, aunque segùn el pronostico alcanzará 45 kts.

Dirección Florida para cojer el rebufo de la Corriente del Golfo a la vez que se debilita.

FORECAST POSITIONS AND MAX WINDS

INIT  08/0900Z 27.2N  69.4W   40 KT  45 MPH
12H  08/1800Z 27.2N  69.7W   40 KT  45 MPH
24H  09/0600Z 27.4N  70.0W   45 KT  50 MPH
36H  09/1800Z 28.2N  70.5W   45 KT  50 MPH
48H  10/0600Z 29.2N  70.8W   45 KT  50 MPH
72H  11/0600Z 31.5N  68.8W   45 KT  50 MPH
96H  12/0600Z 37.5N  59.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
120H  13/0600Z...ABSORBED BY FRONTAL SYSTEM

$$
FORECASTER STEWART

Saludos.

Buen aspecto en el canal visible, convección entorno al centro.

Sigue el patrón de tormenta subtropical, con el centro repleto de aire seco


Cuestion de tiempo que complete la transición antes de marchar en dirección N

Pues el NHC dice que se encuentra cerca de ser catalogado como sistema tropical.

SEAN APPEARS TO BE MAKING A TRANSITION INTO A MORE TROPICAL SYSTEM
WITH DEEP CONVECTION FORMING IN A CURVED BAND RELATIVELY CLOSE TO
THE CENTER.  THIS IS ALSO REFLECTED IN THE SATELLITE INTENSITY
ESTIMATE FROM TAFB...WHICH USED A CURVED BAND DVORAK PATTERN
INSTEAD OF A SUBTROPICAL CLASSIFICATION.  SINCE SEAN IS STILL NEAR
AN UPPER-LEVEL LOW...I HAVE CHOSEN TO KEEP IT SUBTROPICAL ON THIS
ADVISORY...AND THE WIND SPEED WILL REMAIN 40 KT.  THE CYCLONE WILL
LIKELY BECOME TROPICAL BY THE END OF THE DAY AS MOST OF THE MODEL
GUIDANCE SHOW AN UPPER-LEVEL ANTICYCLONE BUILDING OVER SEAN.

Seguiremos observando, por que yo tampoco lo tengo tan claro.

Sean un poco más fuerte.

19LSEAN.45kts-999mb-278N-695W

NHC dice que Sean es 100% Tropical.

CONVECTION HAS FORMED NEAR THE CENTER OF SEAN THIS AFTERNOON WITH A
BANDING FEATURE PERSISTING IN THE NORTHEASTERN QUADRANT.  SINCE THE
STORM IS A LITTLE FARTHER FROM THE UPPER-LEVEL LOW...WITH A WARM
CORE APPARENT ON AMSU ANALYSES AND A SMALLER RADIUS OF MAXIMUM
WINDS AS SEEN IN ASCAT DATA...SEAN NOW HAS ENOUGH CHARACTERISTICS
TO BE CONSIDERED TROPICAL.  THE MAXIMUM WINDS ARE SET TO 45 KT

Y ojo que el pronóstico lleva a Sean a un pico de 55 kts, ojo no vayamos a tener sorpresa en forma de Huracán.

Sean no presenta muy buen aspecto, sobre todo convectivamente hablando.



Aunque el NHC sigue insistiendo en un leve fortalecimiento en las próximas 12-24 horas.

SEAN IS IN A REGION OF LIGHT/MODERATE VERTICAL WIND SHEAR NEAR THE
CENTER OF THE CUT-OFF LOW.  THE DYNAMICAL MODELS SUGGEST THE
PRESENT SHEAR SHOULD CONTINUE FOR THE NEXT 12-24 HOURS...FOLLOWED
BY A SIGNIFICANT INCREASE IN SHEAR CAUSED BY THE TROUGH APPROACHING
FROM THE WEST. THIS SHOULD ALLOW SEAN TO STRENGTHEN SOME TODAY...
FOLLOWED BY A WEAKENING TREND AFTER 24 HOURS.

FORECAST POSITIONS AND MAX WINDS

INIT  09/0900Z 27.9N  70.4W   45 KT  50 MPH
12H  09/1800Z 28.4N  70.7W   50 KT  60 MPH
24H  10/0600Z 29.4N  70.7W   50 KT  60 MPH
36H  10/1800Z 30.6N  69.7W   50 KT  60 MPH
48H  11/0600Z 33.1N  67.4W   45 KT  50 MPH
72H  12/0600Z 38.5N  59.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
96H  13/0600Z...DISSIPATED

$$
FORECASTER BEVEN

A ver de lo que es capaz el amigo SEAN.