Radar loop of Hurricane Audrey in 1957

[MGC]

The Lake Charles La NWS office has posted an interesting article of the 50th anniversary of Hurricane Audrey. Included is an hourly radar mosiac of nearby radars as Audery makes landfall. Note: it appears that Audrey was entraining dry air as it approached the coast. See for yourself here:

http://www.srh.weather.gov/lch/tropical/Audrey@50.php

[Stratosphere747]

Here is a quick comparison of Audrey and Rita. I strongly doubt Audrey was a 4, but the lack of evacuation propagated the loss of life.

http://www.srh.noaa.gov/lch/rita/rita_audrey.php

[Berwick Bay]

Thanks MGC for your report on one of the very greatest hurricanes in American History. What an unusual meterological event this was. A major hurricane in June in the Gulf of Mexico. Extreme tidal surges for several hundred miles to the east of the center (the entire La. Coast). Combination of poorly worded warnings and a populace not expecting this type of event in June. I was a small child and have no memory of the event. But yet, I do. I received recollections from my father who worked on the docks at Berwick La. at the time. The water line in his net shop on the lower Atchafalaya River (about 18 miles up river from the Bay) showed evidence of a massive storm surge here about 150 miles east of the point of landfall near the La.- Tex. border. And so Audrey also belongs to me. At least 500 people were killed, many of them children.

[tailgater]

Nice stuff MGC, Audrey was to SW La. as Betsy was to SE La. then came Katrina and Rita. Oh yeah, radar has advance just a bit huh.

[Jagno]

Both of my parents were here in Audrey and both were still here for Rita. They both agree that the physical devastation resulting from Rita is far greater than that of Audrey, however, lives saved were phenominal. The two lives that were referenced above both were not strictly storm related. The older man had a heart attack and their has been ongoing rumor of substance abuse in the younger man. Either way, I don't wish this on anyone, anywhere at any time.

[wxman57]

It's hard to say how strong Audrey's max winds were at landfall. It's possible Audrey COULD have been a Cat 4, but iwth Cat 4 winds confined to only a small area, perhaps a few square miles, with much lower winds around the rest of the eyewall. That's the problem with only considering the max sustained winds to classify a hurricane (like SS). Rita clearly had a much larger area of hurricane-force winds or greater, and THAT was the reason for the much larger storm surge and greater expanse of high winds onshore.

[BreinLa]

I was 5 years old and that was my first hurricane. I do remember evacuating to a local High School, I lived in Vermilion Parish and remember the winds and being in that school with no power and walking down the hall holding my daddys hand. So strange that I remember this being so young, but I have always remembered.

[MiamiensisWx]

This is an intriguing study. The comparisons between Audrey and Rita demand an interesting study of the complexity and variables of eyewall structures. Both storms featured a large windfield, but the maximum sustained winds were confined to a very small portion of the core. If sfc observations can be trusted, both tropical cyclones did have similar gusts (and/or sustained values), but Rita possibly featured a slightly narrower swath of high winds.

It is very difficult to determine the exact maximum winds of any system, and the current debates on recent storms' intensities begs the question of whether we can rely on estimates for older storms (high or low). If we take a basis of our present knowledge, Audrey may have briefly peaked at the lower end of Category 4 intensity in the Gulf of Mexico, prior to weakening before landfall as a weaker system. At the same time, radar imagery was inaccurate at the time of Audrey, so we do not have dynamic analysis of its structure. Most data does suggest that Audrey likely weakened before landfall, but the degree of weakening is unknown (like the storm's peak intensity).

The problem is evident. There are many variables, and many factors affect the wind damage and dynamics of tropical systems. Audrey struck the region when Cameron was less populated than 2005; even in 2007, the area does not feature extensive development. This illustrates the lack of observations for Audrey. This demonstrates that Audrey could be classified as a weaker or stronger system at landfall. In addition, downbursts (and gusts) created most of the wind damage in many historical and recent storms; thus, it exemplifies the weaknesses of the Saffir-Simpson Scale. Audrey's angle of approach may have enhanced the large surge, and the geography of the region allowed the surge to extend inland.

[CrazyC83]

Was Audrey a small hurricane? If it was comparable in size to Rita, I'd say it was really only a Category 2 with ~105 mph winds.

If Katrina hadn't happened (which created a panic situation with the tragedy fresh on their minds), I think Rita's death toll would have probably been up where Audrey's is, or at least close to it.

[Derek Ortt]

http://www.aoml.noaa.gov/hrd/Landsea/12Tides.pdf

This was posted a while ago on here. This study by Brian Jarvinen found that the maximum winds in Audrey were of CAT 1 intensity (let me restate, these are the findings of Brian Jarvinen, former member of NHCs storm surge unit and took a regular shift as a hurricane forecaster as well)

However, the broad wind field caused the high surge (and this does not surprise me since small cat 1 Lili brought a 12 foot surge to the same area)

Audrey as the bench mark... no way, Jose. A bad storm to be sure though.

The region got very lucky with Andrew in that it made landfall at about a 20 degree angle, much like how Elena did when it struck Mississippi. That eliminated most of the tidal surge (why cannot all canes strike with that angle), and let the winds die down significantly over the swamps. Had Andrew came straight in, the Louisiana Coast would have been totally obliterated

[Derek Ortt]

also interesting to not that Gavleston did NOT take a direct hit from the 1900 hurricane according to that report. Seems like it was in a similar position as was Pensacola in Ivan (still close enough to cause severe destruction)

[Berwick Bay]

I don't know Mr. Orrt. Derek said this

This was posted a while ago on here. This study by Brian Jarvinen found that the maximum winds in Audrey were of CAT 1 intensity (let me restate, these are the findings of Brian Jarvinen, former member of NHCs storm surge unit and took a regular shift as a hurricane forecaster as well)

However, the broad wind field caused the high surge (and this does not surprise me since small cat 1 Lili brought a 12 foot surge to the same area)

I am only a lowly peon here, no met degree for sure, but I wonder if a better explanation would not be the usual North Gulf Coast 'weakens before landfall' syndrome. I don't have the numbers in front of me, but seems like pressure and wind readings taken by Aircraft Recon (while storm was 24 hours from landfall) supported a storm of much greater than Cat 1 Intensity. Also there were those unofficial readings taken by oil rigs of gusts of 180 mph (strictly unofficial). Yes a large windfield and a massive surge, but judging from what we have seen with recent huge surges and Gulf Storms, I would think that a powerful storm offshore weakening 'somewhat' before landfall might be a better explanation. And here I go again, arguing about Categories! And this about a storm which brought a 14 ft surge (before the days of coastal erosion) and a VERY SIGNIFICANT SURGE for hundreds of miles to the east (surge was felt much further east than Rita, and MUCH MUCH FURTHER EAST than Lili.

[Derek Ortt]

I was thinking the same, maybe Audrey did drop to 943 but weakened to 955 at landfall. That would be consistent with the unpublished study mentioned in the Katrina report that documented EVERY cane striking the NGC with a pressure below 973mb weakening before landfall (Erin in 1995 was intensifying and struck with a pressure of 973mb). However, I have not looked at the data to be sure, so I cannot firmly comment on the matter.

One has to remember that the NGC is at 30N. Shear starts to play a significant role once one moves into the mid latitudes (where the NGC is located at). Major hurricanes are far more vlunerable to shear than weaker ones based upon some research I have done in the past. That, along with the lower heat content and possible dry air intrusions from the land may be what slaps down these NGC canes

[terstorm1012]

Derek, did you or someone with UMiami write a paper about that last year?

I have the CD from one of the AMS Conferences but the paper isn't on there. Is it available anywhere on the web or in any academic journals? I could go to the library to look it up or look back through AMS's archives...thanks in advance.

[Berwick Bay]

The day of reckoning might occur with the N Gulf Storm that "does not weaken before landfall". Its not a given that we can always expect this.

[Derek Ortt]

I did not write that

The link I gave is on the HRD website. It was written by Brian Jarvinen, who is a storm surge expert, worked for NHCs storm surge unit and took a regular shift as a specialist (even though his title was not hurricane specialist) until he retired in 2004. It is too long to be in an AMS journal or have been written for an AMS conference

I have never worked with SLOSH, though maybe in the future I will. I cannot predict the future without sound data, lol

[CrazyC83]

I was thinking the same, maybe Audrey did drop to 943 but weakened to 955 at landfall. That would be consistent with the unpublished study mentioned in the Katrina report that documented EVERY cane striking the NGC with a pressure below 973mb weakening before landfall (Erin in 1995 was intensifying and struck with a pressure of 973mb). However, I have not looked at the data to be sure, so I cannot firmly comment on the matter.

One has to remember that the NGC is at 30N. Shear starts to play a significant role once one moves into the mid latitudes (where the NGC is located at). Major hurricanes are far more vlunerable to shear than weaker ones based upon some research I have done in the past. That, along with the lower heat content and possible dry air intrusions from the land may be what slaps down these NGC canes

955 is really low for a Category 1 hurricane, although Katrina and Rita proved that pressures and wind don't seem to always relate very well in the northern Gulf if it involves a large hurricane.

[Berwick Bay]

Yes Crazy, 955 is a ridiculously low pressure for a Cat 1. I think the evidence strongly favors a major hurricane in the Gulf of Mexico in June, which weakened somewhat before landfall. Recent storms have shown how often this happens, however, I don't believe that this weakening is automatically a given. I would think that if upper air conditions ie. an upper level high were centered and present along the northern Gulf coast, you then couldn't rule out a strengthening system.

[GoldenTriangle]

I weathered Audrey...I left for Rita...In SETex the destruction from Audrey didn't begin to compare to Rita.

The piles and piles of snakes after Audrey were unbelievable