Previsão e Seguimento Furacões (Atlântico 2007)

[Vince]

Re: Época Furacões 2007 (Atl. Norte)

Ponto de situação no Atlântico

A tal depressão prevista pelo GFS na 2ª feira no mar das Caraíbas não se concretizou. Neste momento nada de relevante a assinalar. As temperaturas das águas estão muito altas em vários locais, mas o shear, a humidade, etc, é muito desfavorável. E também há muita e areia e pó do Sahara a ser transportada quase até às Caraibas.

Entretanto ao sistema que estava a NE das Bahamas o NRL chama-lhe oficialmente o INVEST 91L e mantem-no sob observação.

Entretanto há uma situação em 28N49W que poderia ser eventualmente interessante para nós, Açores ou Madeira, mas não deve dar em nada... além do mais move-se para já no sentido NW.

De qualquer forma se o NHC tem um floater satélite sobre este local, é porque lhe encontraram algum interesse, por pequeno que seja.

http://www.ssd.noaa.gov/PS/TROP/trop-atl.html (escolham o 4º floater)

DEEP LAYERED LOW COVERS THE
CENTRAL ATLC N OF 18N BETWEEN 39W-56W WITH THE UPPER LOW NEAR
29N50W AND THE 1018 MB SURFACE LOW NEAR 29N51W. A SURFACE TROUGH
EXTENDS FROM 31N49W ALONG 27N47W TO 23N50W. THESE FEATURES ARE
EMBEDDED WITHIN DRY AIR AND ARE ONLY ABLE TO GENERATE A NARROW
BAND OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90 NM E
OF THE SURFACE TROUGH BETWEEN 24N-28N.

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

Probabilidades ...

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

As últimas previsões do NHC apontam para um época acima do normal:

O relatório: http://www.noaanews.noaa.gov/stories2007/s2864.htm

 

[Vince]

Re: Época Furacões 2007 (Atl. Norte)

No Atlântico não há grandes novidades, windshear continua desfavorável, mas as coisas começam gradualmente a parecer mais interessantes nas Caraíbas e Golfo do México. Dos muitos modelos, há pelo menos um que indica algum desenvolvimento nos próximos dias.

Discussão

THE GULF OF MEXICO...
PRONOUNCED UPPER TROUGHING COVERS THE MAJORITY OF THE GULF
EXTENDING SWD FROM THE ROCKIES TOWARD THE YUCATAN PENINSULA. THE
COMBINATION OF UPPER DIFFLUENCE TO THE E OF THE TROUGH AXIS AND
LOW TO MID LEVEL CONVERGENCE NEAR A LOW LEVEL TROUGH BOUNDARY
ALONG 87W S OF 23N IS FUELING SCATTERED TO NUMEROUS SHOWERS AND
TSTMS S OF 25N BETWEEN 83W-88W. IR IMAGES AND LIGHTNING DATA
SUGGEST THAT THE ASSOCIATED MORE ACTIVE WEATHER IS IN THE NW
CARIB. RELATIVELY QUIET CONDITIONS...PATCHY MID-HIGH LEVEL
CLOUDS...EXIST ELSEWHERE. AT THE SFC...A 1023 MB HIGH PRES IS
CENTERED OVER NE GEORGIA. THE TIGHTENED PRES GRADIENT BETWEEN
THE HIGH AND TROUGH NEAR THE YUCATAN CHANNEL IS PICKING UP ELY
WINDS TO 20-25 KT IN THE FL STRAITS AND 15-20 KT ELSEWHERE IN
THE E GULF. THESE WINDS LIGHTEN AND VEER TO THE S/SE IN THE W
GULF ON THE W PERIPHERY OF THE RIDGE. LOOKING AHEAD A DAY OR
TWO...THE MAIN FEATURE OF INTEREST IS THE LOW-LEVEL TROUGH
MENTIONED. SEVERAL COMPUTER MODELS SHOW THIS FEATURE MOVING NE
INCREASING WINDS AND PULLING TROPICAL MOISTURE ACROSS THE E GULF.

THE CARIBBEAN SEA...
SCATTERED SHOWERS AND TSTMS PERSIST ACROSS THE W CARIB NAMELY W
OF 81W...WITH THE GREATEST AREA OF CONVECTION APPROACHING THE
WRN TIP OF CUBA FROM THE SW. THIS MOISTURE IS ASSOCIATED WITH A
LOW-LEVEL TROUGH WHICH RUNS FROM NICARAGUA TO THE YUCATAN
CHANNEL CONTINUING INTO THE SE GULF. VIS IMAGES DISPLAY A BROAD
ENVELOPE OF CYCLONIC TURNING IN THE LOW LEVELS...ALTHOUGH QSCAT
AND SFC OBS LIKELY INDICATE THAT THE MORE SUBSTANTIAL AMPLITUDE
IS OFF THE SFC. ASSOCIATED ISOLATED TSTMS EXTEND FURTHER E
BETWEEN 74W AND 81W MAINLY S OF JAMAICA. FARTHER E...THE TAIL
END OF AN ATLC SFC TROUGH EXTENDS JUST N OF HISPANIOLA. UPPER
DIFFLUENCE TO THE E OF THIS BOUNDARY IS SUPPORTING SCATTERED
SHOWERS AND ISOLATED TSTMS S OF PUERTO RICO AND ACROSS THE
VIRGIN ISLANDS AS DEPICTED ON DOPPLER RADAR FROM SAN JUAN. A
WEDGE OF DRY STABLE AIR ALOFT EXTENDS ACROSS THE WINDWARD
ISLANDS TO NEAR 15N71W PROVIDING FAIR WEATHER FOR THE SE PORTION
OF THE CARIB SEA. LOOKING AHEAD...COMPUTER MODELS SUGGEST THAT A
FAIR AMOUNT OF MOISTURE WILL REMAIN IN THE W CARIB OVER THE NEXT
FEW DAYS AS THE TROUGH SLOWLY PUSHES NE.

 

[Vince]

Re: Época Furacões 2007 (Atl. Norte)

A ficar mais interessante o mar das Caraíbas. Grande bolha de convectividade nas últimas horas.

A Bárbara no Pacífico Este e a imensa convectividade com trovoadas brutais desde o mar das Caraíbas e América Central, até à zona do Pacífico Este onde está a Barbara.

Falta o mais importante, mas parece que já há qualquer coisa em 19n87w ...

The Caribbean Sea...
All the numerous strong showers and thunderstorms in the eastern
Pacific Ocean...from 10n to 15n between Central America and
94w...are not related to Tropical Storm Barbara. This rain in
the eastern Pacific Ocean is related to a middle to upper level
cyclonic circulation center over interior sections of Central
America. A 1006 mb surface low pressure center developed at
31/0900 UTC near 19n87w near the Banco chinchorro...just east
of the Yucatan Peninsula. A trough GOES from the low center
to El Salvador near 13n88w. Numerous strong showers and
thunderstorms are from 16n to 21n between 80w and 86w."

IR/Escala Rainbow

Vapor de água

 

[Vince]

Invest 92l

Já é oficialmente o INVEST 92L, ou seja, o 3º Invest antes do início da época ofical (amanhã)

Para já não apresenta qualquer circulação e o windshear não sendo baixo, também não é agressivo de todo, cerca de 10-20 nós, pelo que existem razoáveis hipoteses de evoluir para depressão tropical.

----------

Entretanto Bill Gray e Phil Klotzbach publicaram o habitual update da previsão para a época, mas em relação ao anterior update de Abril, parece não haver alterações.

ABSTRACT
Information obtained through May 2007 continues to indicate that the 2007 Atlantic hurricane season will be much more active than the average 1950-2000 season. We estimate that 2007 will have about 9 hurricanes (average is 5.9), 17 named storms (average is 9.6), 85 named storm days (average is 49.1), 40 hurricane days (average is 24.5), 5 intense (Category 3-4-5) hurricanes (average is 2.3) and 11 intense hurricane days (average is 5.0). The probability of U.S. major hurricane landfall is estimated to be about 140 percent of the long-period average. We expect Atlantic basin Net Tropical Cyclone (NTC) activity in 2007 to be about 185 percent of the long-term average.

This late May forecast is based on a newly devised extended range statistical forecast procedure which utilizes 40 years of past global reanalysis data and is then tested on an additional 15 years of global reanalysis data. Analog predictors are also utilized. We have maintained our forecast from our early April prediction due largely to the continued trend towards cooler equatorial Pacific sea surface temperatures. Currently, neutral ENSO conditions are observed. We expect either cool neutral or weak-to-moderate La Niña conditions to be present during the upcoming hurricane season. Tropical and North Atlantic sea surface temperatures remain well above their long-period averages.

http://typhoon.atmos.colostate.edu/forecasts/2007/june2007/

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

Modelos sobre este sistema depressionário:

embora outros modelos apontem para uma fraca circulação aliado a outras condições, pelo menos por agora desfavoráveis a algum desenvolvimento tropical

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

O NHC já apresenta a possibilidade no Golfo do México (15h UTC):

 

[Vince]

Invest 92l

O sistema 92L não evoluiu para depressão tropical, mas está no entanto a provocar bastante precipitação que será muito bem recebida na Flórida, a braços com uma seca brutal.

Se evoluisse seria mesmo muito parecido com a 1ª tempestade tropical do ano passado, Alberto, que se formou a 10 de Junho.

Tropical Storm Alberto (2006)

http://en.wikipedia.org/wiki/Tropical_Storm_Alberto_(2006)

 

[Vince]

Invest 92l

No Loop parece esforçar-se para criar uma circulação de superfície.

http://wwwghcc.msfc.nasa.gov/GOES/goeseastconus.html

Neste momento está lá um voo RECON, se encontrar uma circulação fechada e continuar a evoluir assim acho que talvez teremos o Barry ainda hoje.

 

[Vince]

Invest 92 L

Acabou o voo RECON.
Confirma-se uma circulação fechada, confirma-se um warm-core e encontraram uns surpreendentes ventos de 52 mph.

Vortex Data Message
Storm Name: INVEST (BBL)
Mission Number: 01
Flight ID: AF307
Observation Number: 11
Time: 18:58:40Z
Latitude: 23.9°N
Longitude: 85.8°W
#NAME?
Minimum height at NA mb NA m
Est. Surface Winds Observed: 52 mph
Distance and bearing from center to max surface wind: 13 mi SW (222°)
Maximum flight level wind: NNW (329°) @ 60 mph
Distance and bearing from center to max flight level wind: 13 mi SW (221°)
Sea level pressure: EXTRAP 1000 mb
Max flight level temperature outside the eye: 72°F at 1001 feet
Max flight level temperature inside the eye: 75°F at 1001 feet
#VALUE!
Eye character: NA
Eye shape: NA
Eye diameter: NA
#VALUE!
Navigation / Met Accuracy: 0.02 / 3 nm
MAX FL WIND 52 KT SW QUAD 18:55:10 Z
SLP EXTRAP FROM 1500 FT.

Vamos lá ver o que fará o NHC com estes dados.

 

[Vince]

Barry

NHC

104
WTNT32 KNHC 012035
TCPAT2
BULLETIN
TROPICAL STORM BARRY ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022007
500 PM EDT FRI JUN 01 2007

...TROPICAL STORM BARRY FORMS IN THE GULF OF MEXICO...

AT 5 PM EDT...2100 UTC... A TROPICAL STORM WARNING HAS BEEN ISSUED
FOR THE WEST COAST OF FLORIDA FROM BONITA BEACH NORTHWARD TO KEATON
BEACH...AND A TROPICAL STORM WATCH HAS BEEN ISSUED FROM NORTH OF
KEATON BEACH TO ST. MARKS. A TROPICAL STORM WARNING MEANS THAT
TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA
WITHIN THE NEXT 24 HOURS AND A TROPICAL STORM WATCH MEANS THAT
TROPICAL STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH
AREA...GENERALLY WITHIN 36 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 500 PM EDT...2100Z...THE CENTER OF TROPICAL STORM BARRY WAS
LOCATED NEAR LATITUDE 24.2 NORTH...LONGITUDE 85.5 WEST OR ABOUT 320
MILES...520 KM...SOUTHWEST OF TAMPA FLORIDA AND ABOUT 235 MILES...
375 KM...WEST OF KEY WEST FLORIDA.

BARRY IS MOVING TOWARD THE NORTH NEAR 12 MPH...19 KM/HR. A GRADUAL
TURN TO THE NORTH-NORTHEAST WITH AN INCREASE IN FORWARD SPEED IS
EXPECTED DURING THE NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER
GUSTS. NO SIGNIFICANT CHANGE IN STRENGTH IS ANTICIPATED BEFORE
BARRY REACHES THE COAST.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 90 MILES...150 KM
MAINLY TO THE NORTH AND EAST OF THE CENTER.

MINIMUM CENTRAL PRESSURE REPORTED BY A RECONNAISSANCE AIRCRAFT WAS
1000 MB...29.53 INCHES.

COASTAL STORM SURGE FLOODING OF UP TO 3 TO 5 FEET ABOVE NORMAL TIDE
LEVELS...ALONG WITH LARGE AND DANGEROUS BATTERING WAVES...ARE
POSSIBLE IN THE WARNING AREA NEAR AND TO THE RIGHT OF WHERE THE
CENTER OF BARRY MAKES LANDFALL.

BARRY IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS OF 3 TO 6
INCHES OVER THE FLORIDA KEYS AND PENINSULA INTO SOUTHEASTERN
GEORGIA WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 10 INCHES.

REPEATING THE 500 PM EDT POSITION...24.2 N...85.5 W. MOVEMENT
TOWARD...NORTH NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...45 MPH.
MINIMUM CENTRAL PRESSURE...1000 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 800 PM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 1100
PM EDT.

$$
FORECASTER AVILA

http://www.nhc.noaa.gov/

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

A importância do Voo de reconhecimento.. ainda hoje lhe davam uma pequena margem para desenvolvimento tropical.. afinal escondia a sua força...
Nada como começar a Época de Furacões com uma tempestade Tropical

 

[Rog]

Re: Época Furacões 2007 (Atl. Norte)

Embora cedo, comparando a actual situação das duas primeiras tempestades tropicais até ao momento com 2005 relativamente a datas:

 

[Vince]

Barry

Barry durante muitas horas ficou com aspecto estranhissimo, ficou completamente despido. Toda a convectividade devido à acção do windshear foi empurrada para cima da Florida. Na verdade há aqui alguma dose de mistério com o Barry, dadas as condições adversas em que se desenvolveu, cerca de 30/40 nós de windshear desde ontem, quando por norma os 20/25 nós costumam ser o limite.

Mas ontem a classificação como TS foi acertada, após o meu último post chegaram a encontrar ventos ainda mais fortes, quase no limite de Furacão 1, e uma pressão um pouco mais baixa.

Agora já parece querer criar novamente convectividade mais próxima do centro.

http://www.nrlmry.navy.mil/tc-bin/t...s&AID_DIR=/TC/tc07/ATL/02L.BARRY/tpw/microvap

Tem sido a tempestade perfeita para partes da Florida. Não provoca estragos e traz chuva que fazia muita falta. Mas não está posto de parte a hipotese de ocorrerem pequenos tornados ou trombas marinhas.

Radar

http://radar.weather.gov/ridge/Conus/southeast.php

000
WTNT32 KNHC 020841
TCPAT2
BULLETIN
TROPICAL STORM BARRY ADVISORY NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022007
500 AM EDT SAT JUN 02 2007

...POORLY-ORGANIZED BARRY ACCELERATING TOWARD THE NORTH-NORTHEAST...

A TROPICAL STORM WARNING REMAINS IN EFFECT FOR THE WEST COAST OF
FLORIDA FROM BONITA BEACH NORTHWARD TO KEATON BEACH. A TROPICAL
STORM WATCH REMAINS IN EFFECT FROM NORTH OF KEATON BEACH TO ST.
MARKS. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM
CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA WITHIN THE NEXT 24
HOURS. IN THIS CASE...A TROPICAL STORM WATCH MEANS THAT TROPICAL
STORM CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA WITHIN THE NEXT
24 HOURS.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 500 AM EDT...0900Z...THE CENTER OF TROPICAL STORM BARRY WAS
LOCATED NEAR LATITUDE 25.9 NORTH...LONGITUDE 84.2 WEST OR ABOUT 180
MILES...290 KM...SOUTHWEST OF TAMPA FLORIDA AND ABOUT 175 MILES...
280 KM...WEST-NORTHWEST OF KEY WEST FLORIDA.

BARRY IS MOVING TOWARD THE NORTH-NORTHEAST NEAR 15 MPH...24 KM/HR...
AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE WITH AN INCREASE IN
FORWARD SPEED DURING THE NEXT 24 HOURS. THIS MOTION SHOULD BRING
THE CENTER OF BARRY ACROSS THE WEST COAST OF THE FLORIDA PENINSULA
LATER TODAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/HR...WITH HIGHER
GUSTS. SATELLITE IMAGERY SHOWS MINIMAL THUNDERSTORM ACTIVITY NEAR
THE CENTER AT THIS TIME...AND SLOW WEAKENING IS EXPECTED DURING
THE NEXT 24 HOURS. BARRY WILL LIKELY LOSE TROPICAL CHARACTERISTICS
AFTER IT MAKES LANDFALL.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 90 MILES...150 KM
FROM THE CENTER. WINDS NEAR TROPICAL-STORM FORCE ARE OCCURRING
ALONG PORTIONS OF THE SOUTHERN AND EASTERN COASTS OF THE FLORIDA
PENINSULA AT THIS TIME...WITH NOAA BUOY 41009 EAST OF CAPE
CANAVERAL REPORTING GUSTS TO 40 MPH DURING THE PAST FEW HOURS.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB...29.44 INCHES.

COASTAL STORM SURGE FLOODING OF UP TO 3 TO 5 FEET ABOVE NORMAL TIDE
LEVELS...ALONG WITH LARGE AND DANGEROUS BATTERING WAVES...ARE
POSSIBLE IN THE WARNING AREA NEAR AND TO THE RIGHT OF WHERE THE
CENTER OF BARRY MAKES LANDFALL. WIND AND WAVES ASSOCIATED WITH
BARRY ARE PRODUCING DANGEROUS RIPS CURRENTS ALONG PORTIONS OF THE
ATLANTIC COAST OF THE SOUTHEASTERN UNITED STATES.

BARRY IS EXPECTED TO PRODUCE TOTAL RAINFALL ACCUMULATIONS OF 3 TO 6
INCHES OVER THE FLORIDA KEYS AND PENINSULA INTO SOUTHEASTERN
GEORGIA...COASTAL SOUTH CAROLINA...AND COASTAL NORTH CAROLINA.
ISOLATED MAXIMUM AMOUNTS OF 10 INCHES ARE POSSIBLE.

RAINFALL ACCUMULATIONS OF 5 TO 10 INCHES WITH ISOLATED MAXIMUM
AMOUNTS OF 15 INCHES ARE POSSIBLE ACROSS CENTRAL CUBA. THESE RAINS
COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUDSLIDES.

ISOLATED TORNADOES ARE POSSIBLE OVER THE FLORIDA PENINSULA TODAY.

REPEATING THE 500 AM EDT POSITION...25.9 N...84.2 W. MOVEMENT
TOWARD...NORTH-NORTHEAST NEAR 15 MPH. MAXIMUM SUSTAINED WINDS...50
MPH. MINIMUM CENTRAL PRESSURE...997 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 800 AM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 1100
AM EDT.

$$
FORECASTER BEVEN
http://www.nhc.noaa.gov/