EUA- Gigantesca "Nor'easter" prevista para amanhã

Vince

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EUA- Gigantesca "Nor'easter" 15-04-2007

Prevê-se para amanhã, Domingo, uma grande "Nor'easter".

GFS:




Mais informação:


Hurricane-like Nor'easter may form Sunday
A major spring Nor'easter with the capability of causing damage equivalent to a Category 1 hurricane may develop Sunday off the U.S. East Coast. A storm system currently crossing the Pacific coast near British Columbia is expected to dive southeastward across the U.S., possibly triggering a significant severe weather outbreak over Texas, Louisiana, and Arkansas on Friday. The storm will emerge into the Atlantic on Sunday near the Virginia Coast and rapidly intensify. By Monday morning, the GFS model is forecasting a 975 mb low pressure system just off the New Jersey coast, with 50-60 mph easterly winds over Long Island Sound and the waters just south of Long Island. The 00Z UKMET model forecasts an even more intense system, similar in strength to a Category 1 hurricane. Other reliable models are less gung-ho. The European model has the storm bottoming out at a pressure of 985 mb, and the NOGAPS model, 982 mb. However, of great concern is the fact that most of the models forecast a very slow moving system that will weaken only gradually, battering the coast for at least three days. This will allow a long period of time for the tropical-storm force winds over the water to pile up high storm surges in Long Island Sound and along the entire Northeast coast from New Jersey to Maine. Combine this with the arrival of one of the highest tides of the year Monday night--the Spring Tide, which occurs at the time of the new moon in April--and we have the potential for a very serious flooding event. If the worst case scenarios of the models come true, the Tax Day Storm of 2007 could cause extensive moderate to severe coastal flooding, costing hundreds of millions of dollars. The areas at highest risk appear to be New Jersey, New York (especially New York City), Connecticut, Rhode Island, and Massachusetts. Heavy snow is not expected along the coast, but heavy rains may cause flooding problems. As usual, there is considerable uncertainty about the exact track and intensity of the storm, and we'll have a better idea Friday what might be in store for New England. However, I believe there is a greater than 50% chance that this Nor'easter will be strong enough to cause significant storm surge flooding along the New England coast. Damages of at least $100 million are likely.

taxdayjr0.png

Figure. Forecast from the GFS model for 2am EDT Monday April 16, showing a major Nor'easter off the coast of New England.

http://www.wunderground.com/blog/JeffMasters/show.html




Para quem não sabe o que é uma Nor'easter, talvez tenham visto o filme (e livro) "The Perfect Storm" que era sobre uma Nor'easter de 1991, a Halloween Nor'easter, que ficou para a história como a "Tempestade Perfeita"


Algumas explicações sobre a Nor'easter:

What is a Nor'easter?

Nor'easters can occur in the eastern United States any time between October and April, when moisture and cold air are plentiful. They are known for dumping heavy amounts of rain and snow, producing hurricane-force winds, and creating high surfs that cause severe beach erosion and coastal flooding. A Nor'easter is named for the winds that blow in from the northeast and drive the storm up the east coast along the Gulf Stream, a band of warm water that lies off the Atlantic coast.

There are two main components to a Nor'easter:

* Gulf Stream low-pressure system - (counter-clockwise winds) These systems generate off the coast of Florida. The air above the Gulf Stream warms and spawns a low-pressure system. This low circulates off the southeastern U.S. coast, gathering warm air and moisture from the Atlantic. Strong northeasterly winds at the leading edge of the storm pull it up the east coast.

* Arctic high-pressure system - (clockwise winds) As the strong northeasterly winds pull the storm up the east coast, it meets with cold, Arctic air blowing down from Canada. When the two systems collide, the moisture and cold air produce a mix of precipitation.

Winter conditions make Nor'easters a normal occurrence, but only a handful actually gather the force and power to cause problems inland. The resulting precipitation depends on how close you are to the converging point of the two storms.

A powerful Nor'easter can bring travel to a standstill, closing city streets and making it nearly impossible to get anywhere for days. The thing to remember with Nor'easters is that the storm systems occur frequently, but only a few of them are powerful enough to make it into the news. There are two types of Nor'easters:

* Offshore forming - These are the storms you hear about in the news. It is a news-worthy storm that moves east of east-coast cities, dumping lots of heavy snow. In an offshore-forming storm, the hardest hit metropolitan areas are likely to be Washington D.C, Philadelphia, New York City and Boston. Eventually, the system moves far enough north that the Canadian jet stream pushes it off the coast.

* Onshore forming - These storms are less exciting than the offshore-forming storms. They move west of east-coast cities, with gusting winds and mostly rain.

http://science.howstuffworks.com/question595.htm
 


Vince

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EUA- Gigantesca "Nor'easter" 16/4/2007

radhu8.jpg

http://www.nws.noaa.gov/

avnlla3.jpg


sitab9.jpg

http://www.nws.noaa.gov/

High tide in New York brings flooding
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=652&tstamp=200704

Wind, waters rising across the Northeast
http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=651&tstamp=200704

East Coast feels effects of powerful nor’easter
http://www.msnbc.msn.com/id/18090851/


...

The powerful storm that has been the culprit behind severe weather and a snowstorm the past couple of days is now strengthening into a major nor'easter. Already heavy rain is leading to flooding problems over the coastal Northeast, before onshore winds markedly increase over New England causing above normal tides. Powerful winds in the wake of the storm may also topple trees and cause sporadic power disruptions over much of the mid-Atlantic Monday.


storm41507.jpg

Our Severe Weather Center's page displays all the watches and warnings related to this potent storm that will continue to batter the East Coast through Monday as it strengthens into a powerful and slow-moving nor'easter.

Farther north, the East Regional News story details that the band of soaking rain, shown on the Northeast Regional Radar, will continue to spread northward along the Interstate 95 corridor across Maine through tonight. The precipitation may start as a bit of snow across coastal Maine, but will change over to rain later tonight as warmer air moves into the region. The storm has already swamped areas from the Delmarva Peninsula to southeastern New York with 2-4 inches of rain. Some areas around and including the New York City area have received over 5 inches of rain through Sunday evening. Since this much rain has already fallen and more rain is on the way through Monday, flooding remains a major concern along small streams, in low-lying areas, and perhaps even along some major rivers.

Flooding is not only a concern along the immediate coastline due to the drenching rain, but also because the storm's strong winds will pile water up against the shore. In addition, the winds, gusting past 50 mph, will rough up the ocean and cause potentially beach-altering erosion.

With a plethora of moisture wrapping around the storm's center and meeting up with colder air, snow will make a late-season appearance across the interior. According to our Winter Weather Center, up to a foot of snow will blanket the majority of western, central and northern New York to far western Maine through Monday. The higher terrain will top the snowfall totals list with one to two feet.

Not only will the snow make travel extremely difficult, but its weight could down tree limbs and power lines, leading to power outages, and cause roofs to fail. With temperatures staying close to the freezing mark, the snow will be a heavy, packing snow, not light and fluffy. As the storm departs and temperatures begin to moderate, the melting of this snow will bring a threat of flooding during the middle of the workweek.

The threat for downed trees and power lines, and other minor structural damage, will also exist over the rest of the Northeast and the mid-Atlantic, as well as the Southeast, as strong west to northwest winds howl around the back side of the storm through Monday. Drivers of high-profile vehicles should be advised that the winds could easily overturn or steer these vehicles off roadways.

WindsMon041507.jpg


The intense weather all across the East the remainder of this weekend and early this coming week could impact other travelers. Air travelers should check the FAA's Flight Delay map and their specific airline before heading to airports. On the ground, motorists heading where the storm's heavy rain and severe thunderstorms will occur should be prepared for slow travel. The heavy, wet and wind-swept snow across the interior Northeast will make for even worse driving conditions.
http://headlines.accuweather.com/news-top-headline.asp?partner=accuweather&traveler=0
 

Vince

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EUA- Gigantesca "Nor'easter" 16/4/2007

968 mb!

We have quite a deep low pressure system just off the New Jersey coast tonight. A weather station I set up along the Jersey Shore with a fairly accurate barometer recorded a pressure of 967.7mb I believe that is the lowest pressure that particular station has ever recorded in its two years or so at the location.

In addition to having a central pressure lower than 968mb (some hurricanes don't ever get that low) the storm may still be intensifying. Heavy waves of precipitation are still pushing northward into Cape Cod which probably is an indicator of continued deepening, and the pressure at the New Jersey shore continues to drop despite veering(clockwise turning) winds which would normally indicate the center of the storm passing a location and better weather on the way.

I'll leave you with some real time images to track the storm with
90fwbg.gif
Fonte: Eastern And Midwestern U.S. Winter Weather Blog
 

Fernando_

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Obrigado por a informaçao, Vince!
Algumas quantidades de chuva de ontem :rolleyes: :
Philadelphia: 108 mm.
Atlantic City: 56 mm.
Nova Iorque-Kennedy: 65 mm.
Baltimore: 63 mm.
Boston: 38 mm.
Providence (Rhode Island): 77 mm.
 

Vince

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EUA- Gigantesca "Nor'easter" 16/4/2007

Continuo a fazer o seguimento em tempo real (com muita curiosidade) pois é capaz de ser, pelo menos, a tempestade duma década...

Medições duma bóia a SE de NY...
boiass8.jpg



A pressão nesta bóia (posição 40°27'00" N 73°48'00" W) já vai em 966.7 mb ... e a descer...
Penso que seja a pressão mais baixa registada até ao momento nesta tempestade.

Link da Bóia:
http://www.ndbc.noaa.gov/station_page.php?station=alsn6&unit=M&tz=STN

5-day plot - Wind Direction Wind Direction (WDIR): E ( 80 deg true )
5-day plot - Wind Speed Wind Speed (WSPD): 9.3 m/s
5-day plot - Wind Gust Wind Gust (GST): 10.3 m/s
5-day plot - Atmospheric Pressure Atmospheric Pressure (PRES): 966.7 mb
5-day plot - Pressure Tendency Pressure Tendency (PTDY): -4.6 mb ( Falling Rapidly )
5-day plot - Air Temperature Air Temperature (ATMP): 6.3 °C
5-day plot - Water Temperature Water Temperature (WTMP): 6.3 °C
5-day plot - Dew Point Dew Point (DEWP): 5.2 °C
5-day plot - Wind Chill Wind Chill (CHILL): 1.5 °C

Última imagem de radar:
radarbe3.jpg

http://www.nws.noaa.gov/radar_tab.php

Parece haver duas zonas distintas a serem fustigadas com mais intensidade:

Uma mais a norte de NY:
nortefg4.jpg

http://radar.weather.gov/radar.php?product=NCR&rid=enx&loop=yes

E uma mais a sul:
sulry1.jpg

http://radar.weather.gov/radar.php?product=NCR&rid=dox&loop=yes
 

Vince

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Uma estação no Weather Underground regista neste momento uma pressão de 959 hPa.
estds4.gif

Link:
http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KNJBUTLE3

Provavelmente deve ser um erro da estação ...
Pois de contrário estariamos na presença dum valor idêntico à baixa pressão usual num ciclone tropical de categoria 3, segunda a escala de Saffir-Simpson para furacões.

Mapa de inundações neste momento (pontos a vermelhor e a roxo)
inundca2.gif

Fonte: Advanced Hydrologic Prediction Service: Philadelphia/Mount Holly
 

Mago

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EUA: tempestade gigante matou cinco pessoas

Em Nova Iorque mau tempo levou ao cancelamento de 300 voos
Um temporal na costa leste dos EUA provocou a morte de pelo menos cinco pessoas este fim-de-semana. Na região de Nova Iorque, cerca de 300 voos foram cancelados e registaram-se inundações.

De acordo com a edição electrónica do jornal espanhol El Mundo, além das cinco pessoas que perderam a vida, pelo menos mais duas estão desaparecidas.

A enorme tempestade, considerada invulgar para esta época do ano, abarca uma zona que vai desde o estado da Florida, no sul, à Nova Inglaterra, a norte.

No Kansas, três pessoas morreram em acidentes provocados pelo mau tempo e registaram-se outras duas vítimas mortais no Texas. No estado da Virgínia Ocidental foram evacuadas cerca de vinte pessoas de casas e de veículos, devido a inundações. Nesta região, encontram-se desaparecidas duas pessoas.

A região de Nova Iorque tem sido fustigada de forma violenta. O governador Eliot Spitzer já referiu que esta é a pior tempestade dos últimos 14 anos e são esperadas inundações. Cerca de 300 voos foram cancelados, devido às condições do tempo.

Para enfrentar eventuais inundações, o governador já deu ordens para que 3200 soldados da Guarda Nacional se deslocassem para as zonas mais sensíveis, para acudirem a possíveis situações de emergência.

A neve também se tem feito sentir nas regiões mais interiores

In PortugalDiario
 

Vince

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Ontem no Central Park ficou para os registos os 192mm (7.57 inches ) de precipitação, o 2º maior registo de sempre, quase à beira de bater os 210mm de 23 Setembro de 1882.

Nor'easter of 2007 peaks in intensity, continues pounding New England

The Nor'easter of 2007 continues to pound the Northeast U.S. today with flooding rains, high winds, and severe coastal storm surges. The storm peaked in intensity at about 8am EDT with a central pressure of 967 mb--a pressure similar to what one finds in a Category 2 hurricane. However, the nor'easter is not as tightly wound as a hurricane, and the highest winds were were 61 mph gusting to 70mph at 8am EDT on the Maine coast at Matinicus Rock. Winds were 60 mph gusting to 64 mph at the Isle of Shoals C-MAN station on the coast of New Hampshire at 7am EDT this morning.


Huge rains in New York and New Jersey

Central Park in New York City recorded 7.57 inches of rain yesterday, the most ever from a Nor'easter, and their second highest daily rainfall ever measured. The record was set on September 23rd 1882, when 8.28 inches fell during a slow-moving tropical storm. Rainfall total of 5-9 inches were common over much of New Jersey and the New York City area over the past 36 hours (Figure 1), bringing the worst flooding since Tropical Storm Floyd in 1999. Rivervale, NJ has had the most rain I could find thus far--9.3 inches.

Today's running of the Boston Marathon will be a cold, wet one, as 3-5 inches of rain have already fallen over the area, and another 1-2 inches could fall today. The heaviest rains today will affect coastal New Hampshire and Maine, where 5-8 inches are expected.

Coastal flooding
Winds from the 2007 Nor'easter pushed a 2.5 foot storm surge on top of an unusually high "Spring Tide" into the New York City area during this morning's high tide (Figure 2), and a 4-5 foot surge along the western shores of Long Island Sound (Figure 3). The coastal flooding situation may be most serious along the coast north of Boston, where a storm surge of 3-4 feet is occurring during this morning's high tide, and huge waves are battering the coast. Wave heights up to 25 feet were observed just offshore this morning. Coastal flooding is expected all along the Maine and New Hampshire coasts, and downtown Portland, Maine will see water along Commercial Street during high tide today. Waves heights up to 29 feet have been observed this morning off the coast of Maine.

Fonte: Jeff Masters' WunderBlog

Aguns videos que começam a aparecer no YouTube



 
Editado por um moderador:

Vince

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Um relato a partir do Observatório Meteorológico do Monte Washington, o ponto mais alto do estado de New England (1916 m).

O pessoal a trabalhar no local está a enfrentar condições extremas, com rajadas na ordem dos 230km/h...


05:53 AM Mon Apr 16th
Drifts inside the tower...If there was ever a question as to why the Mount Washington Observatory remains a manual station to this day, the current situation on the summit should answer that. Things aren’t going that well, but all things considered, they are fine. But without constant instrument attention...

The whole crew has been forced awake to attend to the instruments in a glaze ice storm that has challenged even the heated instruments. Icing accumulations are ranging from 4 to 6 inches of glaze ice per hour from freezing rain. Wind driven sleet mixed in with the rain is only adding to the challenge, and helmets and double layered face protection is required. The most challenging activity thus far though has been simply going outside, and then re-closing the door. A near futile fight! Winds are blowing nearly straight into the tower, and you can see the results from the picture above.

The effort has been paying off though, and wind speed readings have been kept accurate. The peak gust is 143 mph so far, in winds about as gusty in nature as I’ve ever seen. Winds should increase slightly through the morning, and should slacken a bit this afternoon. We’ll need the break by then!

Jim Salge – Meteorologist

Fonte: Mount Washington Observatory
 

Vince

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Os alertas do NWS não brincam em serviço, até assustam só de ler...

------------------------------------------------------------
BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLOOD STATEMENT
NATIONAL WEATHER SERVICE UPTON NY
1151 AM EDT MON APR 16 2007

...THE NATIONAL WEATHER SERVICE IN UPTON NY CONTINUES THE
RIVER FLOOD WARNING FOR THE SADDLE RIVER AT LODI...

RECORD MAJOR FLOODING IS OCCURRING ALONG THE SADDLE RIVER. AS
OF 1130 AM THE ESTMIATED STAGE WAS 11 TO 12 FEET...OR 5 TO 6 FEET
ABOVE FLOOD STAGE.

LIFE THREATENING FLOODING IS OCCURRING AND WILL CONTINUE.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE UPTON NY
1221 PM EDT MON APR 16 2007

.SYNOPSIS...
INTENSE LOW PRESSURE OVER THE METRO AREA WILL LOOP OVER THE TRI-
STATE AREA THIS AFTERNOON...BEFORE PUSHING SOUTHEAST TONIGHT THROUGH
WEDNESDAY. HIGH PRESSURE WILL THEN BUILD SLOWLY INTO THE REGION
FROM THE NORTH THURSDAY THROUGH SATURDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
NUMEROUS FLOOD WARNINGS ACROSS THE AREA...WITH HARDEST HIT AREAS
BEING NE NEW JERSEY/NYC/AND LOWER HUDSON VALLEY WITH BETWEEN 4 AND
8 INCHES OF RAIN HAVING FALLEN THE LAST 36 HRS.
IN-FACT MAJOR TO HISTORIC FLOODING BEING EXPERIENCED IN NE NEW JERSEY.