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Nor'easter of 2007 slowly winds down

By: Dr. Jeff Masters, 9:25 PM GMT on April 16, 2007

The Nor'easter of 2007 peaked in intensity at 8am EDT today with a central pressure of 967 mb, and has begun a slow decay. At 4pm EDT, the low had weakened to about 979 mb, and was centered over central Long Island. The Nor'easter is forecast to loop across southwest Connecticut and than move south across western Long Island/New York City early this evening as is gradually continues to fill. The worst of the rains and storm surge flooding have already occurred in most areas, but moderate storm surge flooding, freshwater flooding, and high winds will continue to cause problems throughout the Northeast through Tuesday night. A secondary low pressure system is expected to develop Tuesday south of Maine, leading to an increase in winds and storm surge flooding during the high tide cycles on Tuesday along the Massachusetts, New Hampshire, and Maine coasts. Up to 2-3 feet of storm surge flooding is expected along the Massachusetts coast during high tide Tuesday night.

The highest winds at the coast from the storm were 67 mph gusting to 80mph at 2pm EDT on the Maine coast at Matinicus Rock. The highest winds on top of New Hampshire's Mount Washington were 112 mph, gusting to 138, measured at 11am today.

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 had totalled 8.31 inches at Central Park by 9am today. Rivervale, NJ has had the most rain I could find thus far--9.3 inches.

Figure 1. Total precipitation estimated by radar for the Nor'easter of 2007.

River flooding
All-time record flood levels were recorded or are expected on the Ramapo, Rockaway, and Passaic Rivers in New Jersey. Many rivers were 4-5 feet above flood stage in New Jersey today.

Coastal flooding
A 4-5 foot surge along the western shores of Long Island Sound was the highest from the storm. Wave heights up to 29 feet were measured in Massachusetts Bay.

Up to 17 inches of new snow fell in the White Mountains of New Hampshire.

I'll post an update on the Nor'easter on Tuesday. My condolences to all those affected by the tragedy today at Virginia Tech, and by today's storm.

Jeff Masters

Winter Weather

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

nice update
my condeleances too at Virginia Tech

read what happened really horrible
Lowest pressure on land I found was 28.58" at Belmar NJ, on the coast south of Sea Bright. Lowest pressure at a first order station was 28.60 (968.3 mb) at Kennedy International Airport, Queens) The lowest pressure in the water was 28.54" at buoy 44025. These readings and rainfall would make a respectable hurricane! Just the wind was lacking.
So the official lowest pressure is still way above the 956.9 reading in NJ...right? Is that station just wrong? Is it at a higher altitude?
There were no accurate readings at that level. Even the great superstorm of 1993 only dropped to 961 mb.
Winds from the HPC:

BLUE HILL MA 72 MPH 4/16 0514 AM
HINGHAM MA 60 MPH 4/16 0702 AM
WILDWOOD NJ 51 MPH 4/16 0755 AM
on a somewhat unrelated note, check out the latest ENSO UPDATE at this pdf file. It looks like La Nina actually weakened a little, and in addition, there is warmer than average water north of the La Nina area (and south)... including the Eastern Pacific hurricane formation area.
there is warmer than average water north of the La Nina area (and south)... including the Eastern Pacific hurricane formation area.

Yep - read about the Western Hemisphere Warm Pool and what often happens the year after an El Nino during the winter - and specifically, what it does to the Atlantic, which is already well above normal.
This last cold front cooled of SST'S in the GOM a tad but there likely to recover with no problem in the coming weeks.
luckily the water temp off the GA coast is the coldest it has been this late in the spring since 1993.
In fact, I think that the heat is already spreading into the Atlantic - 30*C SSTs are beginning to appear in the SW Caribbean.
water temp off the GA coast is the coldest it has been this late in the spring since 1993


The SST anomaly map shows SSTs that are above normal off the entire U.S. east coast - especially New England (4-5*C above normal). I think that was one of the reasons why the nor'easter got so strong; cold air + warm water = bad news.
Here's another look at SST'S across the basin...

water temps below 65 in the last half of April have not occurred here since 1993.
quick question
how warm does the sea have to be to support a tropical system?
Cool waves after St. Patrick's Day and the first weekend in April have cooled our shelf waters. I don't know if it will last, but here is our local buoy. Link
Tropical cyclones develop over oceans where the surface temperature exceeds 27 degrees Celcius.
There are exceptions, such as the systems that form in the eastern subtropical Atlantic in November/December, but in general the cutoff is 80 degrees for tropical development, and at least 82 for major hurricane development.
how warm does the sea have to be to support a tropical system?

80*F/26*C is generally said to be the minimum temperature; however, extratropical systems can transistion to tropical over water as cool as 70*F or so (this happens quite often with late-season storms).
thanks guys
86F (30C) seems to be the minimum to develop cat 5 hurricanes.
well it probably wont be much longer until the atlantic and gulf are ripe
did we have el nino last season?
The temperature difference between the upper atmsophere and water is more important than the actual water temperature; if the upper atmosphere is colder, the water can also be colder for a given maximum potential intensity. The late season storms that develop over relatively cool waters can do so because the cold-core nature of an extratropical storm helps increase the lapse rate to a level that supports convection (in fact, most extratropical storms will develop a weak warm-core at maturity, called a warm-seclusion).

Warm seclusion
A warm seclusion is the mature phase of the extratropical cyclone lifecycle. This was conceptualized after the ERICA field experiment of the late 1980s, which produced observations of intense marine cyclones that indicated an anomalously warm low-level thermal structure, secluded (or surrounded) by a bent-back warm front and a coincident chevron-shaped band of intense surface winds.[24] The Norwegian Cyclone Model, as developed by the Bergen School of Meteorology, largely observed cyclones at the tail end of their lifecycle and used the term occlusion to identify the decaying stages.[25]

Warm seclusions may have cloud-free, eye-like features at their center (reminiscent of tropical cyclones), significant pressure falls, hurricane force winds, and moderate to strong convection. The most intense warm seclusions often attain pressures less than 950 millibars (28.05 inHg) with a definitive lower to mid-level warm core structure.[24] A warm seclusion, the result of a baroclinic lifecycle, occurs at latitudes well poleward of the tropics.

As latent heat flux releases are important for their development and intensification, most warm seclusion events occur over the oceans; they may impact coastal nations with hurricane force winds and torrential rain.[23][26] Climatologically, the Northern Hemisphere sees warm seclusions during the cold season months, while the Southern Hemisphere may see a strong cyclone event such as this during all times of the year.

In all tropical basins, except the Northern Indian Ocean, the extratropical transition of a tropical cyclone may result in reintensification into a warm seclusion. For example, Hurricane Maria of 2005 reintensified into a strong baroclinic system and achieved warm seclusion status at maturity (or lowest pressure).

It is important not to confuse this with a tropical cyclone, which is also warm-core but occurs over relatively warm water (example).
There was a moderate El Nino up until a couple months ago, peaking at 1.1*C above normal; conditions right now are officially neutral, with a trend towards La Nina conditions (some warming has occurred over the past couple days but I think that is MJO related - the CPC's previous MJO update called for drier than normal conditions over Indonesia and wetter than normal conditions over South America - which is what El Nino does; the MJO has some of the same influences as ENSO except on a much shorter time scale). Here is the most recent MJO update.
Yeah, an El Nio was present last year throughout the year. That wasn't what supressed hurricane activity as much as it was, though; the Saharan Air Layer also helped with that, as well as troughs coming off the East Coast, recurving storms.
Here is a listing of past El Nino/La Nina episodes - the values are for three consecutive months and it has to be at least 0.5*C above/below normal for at least 5 periods in order to be official (notice that the La Nina that developed in late 2005 was not official because it reached the threshold for only 3 periods). Speaking of which, check Kris's blog - years with a bias towards La Nina tend to be the worst years (that is, neutral trending towards La Nina during hurricane season, not La Nina from the start - like 2005).
STL, I was noticing the warming of the waters too over the last couple days, but I didn't want to say anything, just incase I was wrong, and since my vision isn't great, it's a possibility. Also, thank you for the MJO links, I'll definitely take a look at them today.
My husband I attended US Figure Skating Intercollegiate National Team Championships to see our daughter compete for the final time. We left Hanover Sunday at around 9:30 AM in a light rain. The rain became heavier as we headed south on Route 91. Roads were wet, but not hazardous. The last 15 miles of 91 in Vermont was heavy slush and the rain turned to snow. It was a nailbiter into Massachucetts where the roads suddenlty cleared up and were just very wet. We continued south on 91 into and out of snow squals until Springfield. As we arrived at Springfield, the rain was heavy and the roads very wet. There was acutally a line between snow and no snow. North of Soringfield there was snow on the ground. South of Springfield no snow.

We encountered rain all the way into Hartford where we picked up 84. Temperatures were 10 degrees F warmer from Hartford south than the near freezing temperatures up north.

We avoided the flooded areas by staying on 84 and 684 to the Tappen Zee. Rain and fog were dense and nearly obscured the Tappen Zee Bridge. We finally landed home in New Jersey around 2:30 PM.

There's heavy flooding in Bergen County. My sister in Pelham reported flooding. The Hutch went over its banks for the first time in 100 years. The Passiac River has crested and most of the tributaries have crested. The Falls in Paterson should be dramatic for the rest of the week. More rain is in the forecast.

The trip was well worth it. Our daughter took home the silver medal in Intermediate ice dance, not last in the Junior Short Program, and Boston University came in 3rd, two points behind second place U Delaware. A sweet ending for our daughter to 14 years of competitive figure skating. Hope the U of Indiana team made it home okay. They were heading west across New York state by bus.
32. MZT
People should not read too much into the "El Nino years are poor ones for Atlantic Hurricanes" adage.

The 2004 El Nino, was almost as strong as the one in 2006, but the 2004 season was considered a barnburner at the time.
I know this a storm of this magnitude would have caused major flooding anyways but when i read in my local paper that areas have flooded that never flooded before I can't help but think how much of that has to do with excess urban development which causes excess water run off which equals greater flooding.
This storm has killed 11 people so far.

Rains washed out more than 75 roads in New Hampshire, where 200 National Guard troops helped evacuate four towns and reinforce cresting rivers with sandbags.
storm central pressure up to 985 mb now. This is how a storm dies.......
by the way is it me or dos this Nor'easter seem to be moveing back to the W or moveing down S to FL?
are sst above average this year? if it is does that mean more hurricanes are likely in hurricane season?
SSTs are way above average - like 2005

In addition, anomalies have been increasing over the last few weeks.
39. Inyo
as far as I can tell, the 2006 El Nino did not cause any El Nino effects, at least around North America - the rainfall pattern of the winter (extreme drought in California and Florida, wet in the Northwest), the strong cold snap in late winter, and as someone said, little effect on hurricane activity (it may have stimulated the E-Pac some). I believe Australia has had a drought though, which is consistent with El Nino.

Interesting info on the Western Hemisphere Warm Pool. I hope it increases the monsoon this year and helps some with the dry conditions in the Southwest.
what are anomalies? how does that effect hurricane season
Hi everyone. I LOVE this blog, but until now have just read it. My husband is an adjuster, so I read it alot in the hurricane season.

Today- what felt like a hurricane hit us in coastal New Hampshire. I haven't seen anything like it! The closest was the vast hail storm/possible tornado last July. It was crazy. There were flooded out streets, high winds, lakes where fields used to be, etc.

Just wanted to let you all know that you make the weather interesting. I look forward each day to logging on and seeing who's online and what you're saying. I have learned a ton.

Just wanted to give you an update from NH- it's not typical that I have anything weather-wise to contribute. I definately lived a bit of nature's wrath today.
Anomalies are, departure from normal. Yellow and Orange indicate warmer than normal, blues and purples indicate cooler than normal as portrayed in the map STL posted. Warmer anomalies mean higher sea surface temperatures which aid in the development of Hurricanes. Higher SST's are only a fraction of what is needed to support a Hurricane, only one piece of the puzzle.
Here is a good explination of how things work in a Hurricane. It is a unique take on how things work but, lets face it, most of us are not going to school to be MET's. I found it very easy to understand without getting lost in verbage.
as for forecasting 07 hurricane season watch out something wicked this way comes the intense nor'easter is only the beginning all indications are showing a nice setup for hurricane season higher than normal sst low shear less dust increase in water vapor over past several weeks and starting at the end of the week a warming to above nor temp by monday of next week and the placement of the high off the bahamas everything falling into place as we progress towards hurricane season
t minus 1057 hrs 16 min to hurricane season
get outta town
Hey everyone,

First, I wanted to say "hello" to all my old friends on here that I haven't talked to and/or seen posting on these blogs in such a long time. Naturally, this has mainly been the result of my own relative absense during the past 7-8 months or so. Moreover, I also wanted to say "hello" to all of you whom I have yet had the pleasure to meet as well.

That being said, I am still extremely busy and most likely won't be able to even respond personally to all the very thoughtful posts in my own blog that I have appreciated so immensely. On the other hand, I did have a few minutes to read through the first page (most recent 50 comments) of this blog, and simply wanted to offer my own personal opinion on a topic I saw discussed herein. As probably most of you already realize, the 2006 Atlantic hurricane season was actually slightly below normal climatologically speaking (average of the past 57 years). With that in mind, it is absolutely correct that the SAL (African dust) did indeed impede tropical cyclone formation, although it is getting too much credit in and of itself, compared to other inhibiting factors that were in place last season. To be most specific, the origination of all the troughiness in coordination with increased vertical wind shear are consistent with the El Nino phase of the ENSO cycle. Consequently, I would most respectfully argue that it was indeed the El Nino phase of the ENSO cycle that had the most significant effect (as it developed late in the season) on tropical cyclone formation, which essentially came to an abrupt halt later in the season. One only has to look at the CPC historical data on the monthly ENSO page to appreciate the aforementioned correlations. In short, the 2006 Atlantic hurricane season was mitigated by both the presence of higher than normal concentrations of African dust from the SAL, and the typical tropical cyclone inhibiting effects of the El Nino phase of the ENSO cycle. Most importantly, I want to wish each and everyone of you a great rest of the night.:)

Most sincerely,
So True Inyo

However I beleave the La Nina if anything takes the moisture father east into New Mexico druning La Nina years. Any moisture that trys to make it north hits that nice cold water and does nothing.
The 8.41" of rain @ Central Park and 28.63" (968.8 mb) would be very respectable for a Cat 2 hurricane......
Anyway, there are now no land observations or buoy observations showing a pressure below 989 mb. This storm is weakening faster than I thought!
Thanks Tony.
As for the E. Pac. hurricane seson: La Nina generally doesn't bode well for tropical development in the tropical E. Pac. However, La Ninas can sometimes induce a pool of warmer than normal SSTs north of the main negative SST anomaly area (which is near the equator). This can aid in the development or sustenance of tropical systems off the coast of W. Mexico. Steering currents aloft are really more dependent on short and mid-term indicators than the ENSO cycle in the Epac, and these upper level winds are crucial in the transport of tropical moisture into the southwest during the summer months. This sort of warm pool north of the main La Nina region actually is present currently...take a look at the latest SST anomaly maps from the BOM. In other words...don't count out the E. Pac. hurricane season just yet...

More at http://www.weatherwest.com
100 Biggest Weather Moments on the Weather Channel
Any thoughts on Andrew being #62??
That storm changed building codes, warnings, Jim Cantore etc what do you guys think? What should be number 1? Katrina??
Oh Shouldn't Weather Underground make the list?
Worldwide,no.Andrew wouldn't crack my top ten,maybe not even twenty.
Those hit by storm get tax extension
WASHINGTON People directly affected by the storm that hit the Northeast on Sunday and Monday are entitled to a two-day extension for filing their tax returns, the Internal Revenue Service said Monday.

Impacted taxpayers will have until midnight Thursday, April 19, to file their taxes. For others, the deadline this year is April 17 because April 15, normally tax day, fell on a Sunday and Monday was Emancipation Day, a legal holiday in Washington D.C.

"Because this unusually forceful storm hit within 24 hours of the filing deadline, we are giving affected taxpayers 48 additional hours," IRS Commissioner Mark Everson said in a statement.

The deadline extension is aimed at helping those directly affected by power outages or public transportation problems such as flight cancellations that made it difficult for people to file their returns on time.

Affected taxpayers, in order to avoid incurring late fees, should mark their paper tax returns with the words "April 16 Storm," the IRS said. Those filing electronically can use their software's "disaster" feature if available.
Actually,I'd put the tri-state tornado ahead of Andrew.
The tri-state tornado is definitely one of the more memorable weather events out there. I'd list Charley, Andrew, Ivan, or Katrina as number 1.
worldwide?No,Andrew is not top ten worldwide.
Oh, no most definitely not. Whoever said it was?
Well,the TWC list is worlwide.That's what we're talking about.I thought so,anyway.
That is what we are taling about, but I forgot it was "worldwide". Still, I'd rate, IN MY BOOK anyway, Andrew, Katrina, Ivan, Charley, and maybe even Mitch or the Great Hurricane of 1780 (DEFINITELY THAT) as the top weather event of all time.
No,no,no,LOL.I can think of several events off the top of my head that outdo EACH of those.
For one,I'd put Wilma ahead of Andrew on the list.For another,what about the European heat wave that killed ten thousand a few years back?Or the 1970 Bangladesh cyclone?
And the tri-state tornado outdoes Andrew and Charley.
Mitch would definitely be near the top.As is the typhoon tht wiped out the Mongol fleet invading Japan(think about the long term consequences).
Does the weather channel's list go back that far in time? Does it just include the USA or is world wide? I actually saw one clip, invention of Gore-Tex (83 I think).

I have counted out the Epac season already. Just look at this PDF...

A dying tropical cyclone brought 2”
of rain to the mountains and deserts of
Southern California during a very
strong El Nio event of 1901-02.

A tropical storm came up into the
Gulf of California and the
southwestern United States, giving the
mountains and deserts heavy rainfall.
Needles received 5.66” of rain, twice
the normal of seasonal rainfall. This
occurred during the El Nio of 1905-

The remnants of a tropical cyclone
moved northward across northern
Baja California into the deserts of
southern California with rainfall of 1
inch at Riverside. This occurred
during the strong El Nio of 1914-15.

Four days of heavy rains from a dying
tropical cyclone brought flooding to
parts of the mountains and deserts of
southern California. Rainfall of 4.38”
fell at Tehachapi in 7 hours on 9.30.
This occurred during the El Nio year
of 1932-33.

4” of rain fell across the deserts and
mountains as a dying tropical cyclone
moved across Baja California into
southwestern Arizona. This was the
second tropical cyclone to affect
California during the busy month of
September 1939. A strong El Nio
contributed to the activity.

A tropical storm moved northward
into northern Baja California and
dissipated with rainfall of up to 4” in
the mountains on 9.30 and exceeding
4” in the mountains on 10.1. This
occurred during the El Nio of 1946-

A hurricane moving north
northwestward just off the west coast
of Baja California moved
northeastward into northern Baja
California and dissipated. Moisture
from this tropical cyclone resulted in
rainfall of 2 to 5” in the mountains
and deserts. Many roads were washed
out in the Imperial Valley, but
otherwise no major damage occurred
in southern California. This occurred
during the El Nio of 1951-52.

A west-northwestward moving
tropical storm southwest of Baja
California dissipated. Moisture from
this storm resulted in rainfall of up to
2” in the mountains and deserts, with
most falling on 9.19. This occurred
during the El Nio of 1951-52.

O and the list goes on and on....

In a totally unrelated topic, I have been seeing a lot of reporters say that what happened @ VA Tech was the worst school mass murder in US history. It was not. The worst happened back in 1927. It was in a small town about 70 miles north of where Indiana, Ohio, and Michigan come together, in a town called Bath. And you can read about it here:
damn the link didn't work try here

first Pacific storm could be rapidly approaching

Quite true. Very strong correlation between strong El Nino events and tropical moisture in CA. La Nina can cause upper lows to form off the SoCal coast during the off-season (summer/fall), and funnel moisture from what few tropical systems may exist into the SW...
What a awfull day for you people!! A heavy storm, killing people - a shooting, killing far more people...
Here it is also frontnews.
My thoughts und prayers are with the people who have to experience such terrible things.
savedbygod - that is an absolut awfull experience, having your child shot at! Hope I never have to go through something like that!
78. Inyo
Thunder01, great site, I bookmarked it and will check in on it later. There aren't enough good CA weather blogs out there.

Lightning 10, my personal opinion is that climate change (human caused, natural, or both) is causing California's climate to change on a more broad scale right now, which means that the normal weather associated with ENSO may not apply. (for instance, 04-05 being mostly ENSO neutral or very weak el nino, a stronger el nino in 06-07 bringing extreme drought).

I had a lot to say about this so I made a blog entry on my own page, since it is not related to the New York storm.


10 mm of juicy rain here in the last 24 hrs.

Sorry to note the bad happenings in the US. Keep strong..........
As far as the EPAC area of question! Seems shear is rather destructive in the area.
A chance for severe weather today.....probably beginning late morning/early afternoon in north-central Texas and up to Oklahoma City.
Enough moisture has moved in and conditions look ripe enough for maybe a line of some type to set up, probably a broken line of thunderstorms around the I-35 corridor. Expect this to become more numerous in mid to late afternoon as this moves east and probably washing out in the Arklatex region early evening tonight.
Main threat should be strong winds and hail. SPC has a 5% chance of tornadoes. Low-topped supercells I expect which means quick and fast tornadoes if they do form.
Have a good day everyone.
hope all stay safe
This was a bad 3 days for the US... with the storm and the unfortunate tragedy. Hope everyone is well.
Quoting Inyo:
Thunder01, great site, I bookmarked it and will check in on it later. There aren't enough good CA weather blogs out there.

Lightning 10, my personal opinion is that climate change (human caused, natural, or both) is causing California's climate to change on a more broad scale right now, which means that the normal weather associated with ENSO may not apply. (for instance, 04-05 being mostly ENSO neutral or very weak el nino, a stronger el nino in 06-07 bringing extreme drought).

I had a lot to say about this so I made a blog entry on my own page, since it is not related to the New York storm.

hey WU look at me look at me what are you going too do about it am talking off key from the blog what are you going too do about it


nothing you can do about it