The Great Southeaster – November 25, 1950

Storm surge in Southport / Courtesy: Pequot Library Association

Connecticut meteorologists love talking about nor’easters but do you know about the state’s biggest southeaster? The “Great Appalachian Storm” of November 25, 1950 was one of Connecticut’s most violent wind storms on record. In some towns the wind speeds in 1950 were only exceeded by the great hurricane of 1938!

The storm was only of modest strength in terms of central pressure – 980ish mb. But what made the winds vicious was the 1050ish mb high near Maine. The freakishly strong pressure gradient produced violent southeasterly and easterly winds across New England. Here are some of the wind gusts recorded in Connecticut on November 25, 1950.

  • Bridgeport – 88 m.p.h.
  • New Haven – 77 m.p.h.
  • Hartford – 100 m.p.h.

The 70 m.p.h. 1-minute sustained wind in Hartford remains the strongest wind recorded for the official Hartford records since observations began in 1904. The second highest value is 64 m.p.h. recorded during the October 3, 1979 tornado. In Bridgeport the sustained wind of 62 m.p.h. is one of the highest on record (since 1948) with the highest occurring during Gloria in 1985 at 74 m.p.h. sustained and two other higher wind speeds during the winters of 1964 and 1969. Note on record: 2-minute sustained winds replaced 1-minute sustained winds in 1995.

Courtesy: PSU/Richard Grumm

For a non-tropical storm there’s no question in my mind that the 1950 southeaster was the most violent windstorm we’ve seen. The standardized anomalies from Richard Grumm at the NWS in State College shows a wide area of +4 standard deviation 850mb winds. That’s quite a low level jet! The winds reached 160 m.p.h. on Mount Washington in the core of that LLJ.

Looking at the reports from that day here in Connecticut temperatures in the warm sector came close to 60º with highs in the upper 50s in Hartford, Bridgeport, and New Haven. The unseasonably warm weather, when coupled with a a ripping low level jet, lead to enough turbulent mixing to mix down destructive winds – in some cases to 100 m.p.h.!

Here are some of the comments from the official weather bureau reports.

  • Hartford – “Of paramount interest in this month’s weather is the occurrence of “The Great Wind Storm of November 25, 1950″. Considering its great extent, extreme weather of various types, and its unusual meteorological character, this storm will be long remembered. At Hartford, E’ly winds averaged the amazing speed of 38 m.p.h. for the entire day of the 25th, and attained gust speeds of at least 100 m.p.h. on at least 3 occasions between 4:30 and 7:30 p.m..”
  • Bridgeport -” Storm of Nov. 25th worst since 1938. Station inundated with 4 to 5 feet of water.”
  • New Haven – “Severe southeast storm on 25th. Extensive wind and water damage to shore fronts. Many trees, wires, antennae down, roofs damaged. Max for 5 minutes: 50 SE at 1:55 PM (17 Hrs.), probably exceeded 8:00-9:00 PM. Fastest single mile: 57 SE at 1:56 PM (17 Hrs.), possible exceeded  8:00-9:00 PM. Gusts: 55 MPH at 1:35 PM; 66 MPH at 4:20 PM; 66 MPH at 7:40 PM; 77 MPH 5 second gust at 4:45 PM… 5 min. max record; fastest mile exceded in Sept. 1903.”

12 UTC Surface Analysis / Courtesy: MWR/NOAA

The strong winds produced widespread tree and power line damage across the state. The winds tore a roof off a dormitory at UConn and ripped shingles off roofs across the state. Several shoreline homes lost their roofs according to a Hartford Courant article from shortly after the storm.

The storm surge flooding was extensive on the coast. In New London the tide reached an impressive 7.58ft MLLW. The only storms higher in the last 100 years are the 1938 hurricane, hurricane Carol, and hurricane Sandy. In Stamford at the Hurricane Barrier the tide reached 9.5ft NGVD which was similar to Irene’s tide level.

Laguardia Airport on 11/25/1950       Courtesy: NYC OEM

Much like Sandy, the storm surge flooded large portions of New York City including the lower east side and Laguardia Airport. Sandy’s surge, however, was much more powerful in the parts of the City, like Staten Island and the Rockaways, with Atlantic exposure.

On the Connecticut shoreline houses, cottages, railroad tracks, and beaches were swept away. Newspaper accounts indicate that the sand was several feet deep on coastal roads and was removed by snow plows. Many people had to be rescued from their homes after refusing to heed evacuation orders.

The storm resulted from an exceptionally deep dip in the jet stream and monstrous closed low that formed over the Appalachians in a trough the went negatively tilted. The easiest way to visualize this is to look at the 500mb height anomalies associated with the low. Much like Sandy, there was a large “block” downstream. In the 11/25/1950 case there was a 350+ meter positive height anomaly over eastern Quebec. The upper level low itself over the central Appalachians was an exceptionally impressive 450+ meter negative height anomaly.

This type of unusually deep system lead to unusually cold weather and extreme snowfall in the Appalachians and the Ohio River valley. The storm is one of the worst blizzards in parts of the country. Steubenville, Ohio recorded 44 inches of snow while the synoptic desert of Pittsburgh dug out from 30.5 inches of snow!

In the southeast U.S. the backside of the storm delivered a bitterly cold air mass. The mercury dropped to -3º in Atlanta, GA. Many observing sites saw their coldest November temperatures on record. 850mb temperatures reached an INCREDIBLE -20ºC over northern Georgia at 12z 11/25/1950.

Courtesy: PSU/Richard Grumm

Not very often do you see a -6 sigma 850mb temperature! The exceptional baroclinicity and phasing resulted in what amounted to one of the most impressive east coast storms of the 20th century.

PSD 20th Century Reanalysis

While we frequently refer to the March 1993 storm as the “storm of the century” the November 1950 storm gives ’93 a run for its money. For east coast storms we really had 2 storms of the 20th century.

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Sandy Sets Records and Reshapes Coast

It’s been a long few days covering Sandy but my long days are nothing compared to the people throughout the northeast who have lost homes, businesses, or even loved ones.

Sandy brought a storm surge that was devastating to the Connecticut shoreline. In many respects, however, we dodged a bullet.

Water levels reached benchmarks that haven’t been seen since the 1938 hurricane in some towns. Thankfully, the peak storm surge was reached several hours before high tide.

The storm moved ashore in New Jersey and winds began to diminish prior to high tide’s arrival. In the case of the central and western Sound the peak wind and surge occurred just an hour after low tide and 5 hours prior to high tide.

Here is a look at the Stamford Hurricane Barrier observed water level, predicted astronomical tide, and residual/surge which is the difference between observed water level and what the astronomical tide would be without a storm surge.

Stamford Hurricane Barrier (Courtesy: Army Corps of Engineers). Green – astronomical tide, Blue – observed water level, Pink – surge/residual.

The maximum storm surge at the Stamford Hurricane Barrier was an incredible 11.24 feet! That surge peaked around 7:00 p.m. when the astronomical tide level was quite low. The maximum water level of 11.03 feet was reached at 10 p.m. when the surge had dipped to 8.73 feet. By high tide (around midnight) the surge had dipped to 4.4 feet.

At the Battery in New York City  the peak surge coincided with high tide. The same occurred along a large swath of the Jersey Shore.

The storm surge, however, was still catastrophic on parts of the Connecticut shoreline even though the worst case scenario was narrowly avoided. Many towns, including Milford and Fairfield, experienced coastal flooding worse than Irene and the worst since the great hurricane of 1938. In New London the tide reached a level not seen since hurricane Carol in 1954.

Had the peak winds (which occurred around 6:00 p.m.) and the peak surge (which occurred around 7:00 p.m.) occurred several hours later the destruction in Connecticut would have been unimaginable.

A last minute increase in the storm’s forward speed saved the state from what would have been its greatest natural disaster since the 1955 flood.

If Sandy made landfall in New Jersey closed to midnight entire neighborhoods would have been decimated, inundated by a storm tide 4 or 5 feet higher than what we saw. This would have most likely claimed lives. Water would have reached places that most in Connecticut would have never thought possible. As bad as Sandy was our state really lucked out. The dire message we were trying to get out along with the governor was necessary given the data we were seeing and the potential for a truly unthinkable event. If you need to see how bad it could have been look just to our west in New York or New Jersey where high tide was several hours earlier.

In East Haven, 2 houses were destroyed and 4 houses will likely be condemned. In Fairfield 5 houses were swept out to sea and at least 12 will likely be condemned. Fairfield’s coastal flooding was the worse since 1938. East Haven’s coastal flooding damage fell short of what was seen last year during Irene.

The actual tide leve in East Haven from Sandy was higher than during Irene. The damage, however, wasn’t as bad. Of the 28 homes destroyed during Irene many weren’t rebuilt. The ones that were rebuilt were raised to avoid surge like this. There simply wasn’t nearly as much to destroy on Cosey Beach!

Another issue that gets overlooked sometimes is that the wave action on the coast from New Haven and points east was greater during Irene. Winds were due easterly in Sandy (parallel to the shore) while during Irene the winds were more backed and southerly. A more onshore wind brought even more significant and destructive wave action to the beaches. It’s the wave action on top of a surge that can start eating through a house. In Farifield, due to the coast’s geography, an easterly wind is able to bring higher and more destructive wave action right to the beaches as the wind is more perpendicular to the West Haven to Greenwich coast.

Hurricane Sandy likely produced winds near category 1 strength along the New Jersey coast. Farther north, the storm produced hours and hours of tropical storm force winds including occasional gusts exceeding hurricane force. The worst of the wind occurred when the boundary layer mixed a bit promoting the efficient transport of stronger winds aloft to the surface.

There’s no question the winds were stronger statewide in Sandy than during Irene. However, with the exception of the immediate shoreline, the tree damage from Sandy was less impressive than Irene.

Here is a look at maximum wind gusts in Connecticut from Sandy and Irene.

  • New Haven* – Sandy: 50 mph / Irene: 67 mph
  • Bridgeport –  Sandy: 76 mph / Irene: 63 mph
  • Groton – Sandy: 75 mph / Irene: 58 mph
  • Danbury – Sandy: 68 mph / Irene: 47 mph
  • Hartford** – Sandy: 54 mph / Irene: 46 mph
  • Willimantic – Sandy: 53 mph / Irene: 51 mph
  • Bradley – Sandy: 62 mph / Irene: 51 mph

* No reports at KHVN past 5 p.m. during Sandy
** No reports at KHFD past 7 p.m. during Sandy

There are several reasons for the parity in tree damage from Irene and Sandy in most towns. One reason is that the trees were mainly bare away from the shore! A leafed tree is much easier to knock over than a bare one. Irene also dropped 5″-10″ of rain across Connecticut prior to and during to the strongest winds. Saturated and weakened soil makes it easier to uproot a tree. Another reason is that Irene and the October snowstorm knocked down a lot of weaker trees and limbs. There was less to destroy after the 2011 storms!

Courtesy: Debra Bogstie / NBC Connecticut – Guilford Green lost at least 6 trees with more substantial damage than seen during Irene. Just a mile or two inland, however, the damage from Sandy was less than Irene.

That said, the hurricane force wind gusts from Sandy within a mile or two of the Sound resulted in substantial damage in some shoreline towns. Structural damage, including roof and siding damage, occurred in Sandy and generally didn’t during Irene.

Meteorologically, this was the oddest storm I’ve ever covered. Strangely, it occurred 1 year to the date after the second oddest storm I’ve ever covered.  I’ve never seen a hurricane take the path this one did. Not even close. In the beginning (7 or 8 days out) it was easy to dismiss some of the computer models as they were predicting something that had never been seen before. As time went on the weather pattern became more clear and it was evident that something truly extraordinary was about to happen.

This hurricane made landfall with a pressure of 946mb making this the strongest storm to make landfall in the northeast in more than 70 years.

Sandy was an incredible storm. It will likely change the way coastal residents,  emergency managers, and government officials  in the northeast think about just how vulnerable our coastline is. The northeast has been lucky in the last several decades with a relatively quiet period of tropical activity. History has shown that hurricanes can move onshore here and they frequently do so with disastrous results.

So far it seems the state and the utilities were prepared for Sandy. The response and the preparation, in my opinion, has been impressive from the governor right on down to local officials.

Our work as a state isn’t done. We need to make sure we are prepared for the “big one” because Sandy wasn’t it. In fact it wasn’t even close to a “doomsday” storm like a repeat of 1938.  Let’s take the lessons learned from the last 3 storms and make sure we are ready for the next hurricane.

Special thanks to the Connecticut National Guard, the Fairfield Police Department and the Army Corps of Engineers for pictures and data. 

Final Report on Tropical Storm Irene Released

The Tropical Cyclone Report for Hurricane Irene was released this week by the National Hurricane Center. There’s not much in here we didn’t already know. Not surprisingly the New Jersey landfall has been downgraded from a hurricane to a 70 mph tropical storm (note: the highest winds were offshore and not on land).

What was a bit of a surprise to me was that Connecticut garnered just 1 mention in the body of the 45-page report. Besides the historic flooding in Vermont and the Catskills the worst impact from Irene in terms of wind damage and storm surge was here in Connecticut.  Here’s the closest reference to Connecticut about the surge that destroyed countless homes, businesses, and roads along our shoreline.

Glad that New York City escaped severe damage but why not mention areas that did experience severe damage?

Connecticut is covered by 3 National Weather Service offices. One in Albany, one near Boston, and one near Long Island. It’s easy to be forgotten here on the outskirts of the 3 service areas. It looks like even the NHC forgot about us too.

The National Weather Service in Taunton, Massachusetts does a nice job including us in emails and communications. I can’t even remember the last time I heard from the other offices.

Irene’s Storm Surge & Wind Damage

The preliminary numbers indicate Irene created a 3-6 foot storm surge across Long Island Sound with tragic results. The surge peaked at high tide (which was already high) and was devastating across Long Island Sound. In some areas, particularly around New Haven, the tide levels were their highest since the 1938 hurricane. Dozens of homes were either totally destroyed or condemned. In Branford and East Haven several structures that have stood since 1938 are now gone.

The towns did a good job getting the word out about evacuations and the storm surge threat was forecast quite well. I think in general the state and town emergency managers did a phenomenal job getting people out of harms way and taking care of the damage right after the storm.

It seems the only hurdle most towns have is getting Connecticut Light and Power out to help them with trees that are tangled in wires or utility poles that are snapped. In many cases public works crews and sub-contracted tree removal crews are sitting in parking lots waiting for CL&P crews. Can’t blame the municipalities for that.

Here are some pictures from the shoreline during and after the storm.

Water St. and River St. in Guilford Sunday Morning along West River

One of Dozens of Trees Down Near Where I Grew up in Guilford

At Least the Vodka Didn't Go Bad

Lockers Destroyed at Owenego Inn in Branford By Surge

Stairs From Boardwalk to Beach Gone

Railing Destroyed, Just Twisted Metal

Entire Side of Hill Eroded from Surge

Part of Linden Ave. Collapsed into Long Island Sound

Drain Pipe Exposed with Guardrail Dangling Over Ledge

More Damage on Linden Ave

Another Look at Erosion Along Road