Revamping the SS Scale

[Hurricane Jed]

Hurricaneman's scale was incredibly confusing. Mainly because a tropical cyclone is like a living creature, it grows and evolves, changes shape and increases in strength so we need the TD, TS and Hurricane classifications.
I liked some of the ideas brunota2003 and SouthDadeFish had and came up with this:

Possibly this might work

HES- Hurricane Effect Scale

Surge Vulnerabilities:
Blue-Very Low
Green-Low
Yellow-Moderate
Orange-High
Red-Very High
Purple-Catastrophic
This is so people know which vulnerability zone they are in. They can look and be like okay we are in the Yellow Zone.

Surge Threat Levels:
Level 1: 0-5ft
Level 2: 6-10ft
Level 3: 11-15ft
Level 4: 16-20ft
Level 5: 21-25ft
Level 6: 26+ft

This is so meteorologist can assign a predicted Level of storm surge to each zone. Example: Hurricane Alberto is approaching the coast, those in the Blue Zone can expect a Level 1 storm surge, those in the Green Zone can expect a Level 2 storm surge and so on and so forth.

Wind Speeds
Tropical Depression 30 or 35 mph
Tropical Storm 39-73 mph
H1: 74-95mph
H2: 95, 100, 105 or 110 mph
H3: 115, 120, 125 or 130mph
H4: 135, 140, 145 or 150 mph
H5: 155, 160, 165 or 170 mph
H6: 175, 180, 185, 190, 195 or 200 mph

If we use the term Category people will think of this as the same as the SS scale. So instead of Category use a capital "H". H1=Cat 1 etc etc and this way older storms could be re-categorized easily using this system. Plus its shorter and rolls off the tongue easier.

Not saying this would work, but tried to come up with something easy for the general public to understand.

[SouthDadeFish]

Crazy, the central pressure or "barometer effect" has only a slight affect on raising the storm surge as compared to the dominant factor, which is wind stress. I cant give you a definite answer about if a very very small cat 4 and incredibly massive cat 1 could have the same peak surge height in the same location, but I guess it is theoretically possible. So much of surge height depends on location and bathymetry. For example if Ike had made landfall on the east coast of FL near Palm Beach the surge would have only been 8 feet instead of 20.

[psyclone]

i seem to recall that pressure has a negligible impact on surge and that it would take a sub 900mb storm to raise sea level 3 feet but perhaps a pro give us a definitive answer.

[SouthDadeFish]

i seem to recall that pressure has a negligible impact on surge and that it would take a sub 900mb storm to raise sea level 3 feet but perhaps a pro give us a definitive answer.

As I said, the lower pressure has a much smaller affect on storm surge when compared to bathymetry and the wind stress on the ocean. As a rule of thumb, a drop of 1mb is about a 1cm increase in storm surge height, so a 100mb drop would be about a 1meter rise in surge height, which is about 3 feet. For example Katrina at landfall had a central pressure not even 100mb less than sea-level pressure, but had about an 8-9 meter surge.

[psyclone]

i seem to recall that pressure has a negligible impact on surge and that it would take a sub 900mb storm to raise sea level 3 feet but perhaps a pro give us a definitive answer.

As I said, the lower pressure has a much smaller affect on storm surge when compared to bathymetry and the wind stress on the ocean. As a rule of thumb, a drop of 1mb is about a 1cm increase in storm surge height, so a 100mb drop would be about a 1meter rise in surge height, which is about 3 feet. For example Katrina at landfall had a central pressure not even 100mb less than sea-level pressure, but had about an 8-9 meter surge.

thanks for the confirmation. location certainly matters. as bad as the surge potential is in the tampa bay area, it is far worse just to the north. Steve lyons mentioned on TWC (during his days as the hurricane expert) that apalachee bay is the most storm surge prone location in the entire atlantic basin and that a major storm could yield a 40 foot surge there. i can't imagine such an event. fortunately, it is sparsely populated. nonetheless, that's just crazy. in 2005 hurricane dennis pushed a massive surge that swamped st marks while the hurricane was hitting about 200 miles away. prior to that tidal gages at clearwater recorded a 5 foot spike. in an enclosed body of water like the gulf, water sloshes like a bath tub. the public at large does not comprehend the extent to which location influences storm surge potential.

[MGC]

As we were getting our stuff together, or making a crisis evacuation from Katrina, the only hurricane I have ever left for....the only thing that stuck in my mind were the thought of Cat-5 winds. I think I read the first third of the Sunday morning advisory of Katrina when I jumped up from my computer and got going. Didn't even consider the surge this despite living close to the beach, 2 blocks or so. I am up on a bluff though and the water came within 100 feet of my uninsured home. I didn't really think of the surge until we were driving down HWY 90 and my husband told me to take a good long look because none of this will be here tomorrow. Sadly he was so right. I was so focused on wind that I missed the greatest killer, the water......MGC

[Hurricaneman]

Amother scale thats really good is Joe Bastardi's scale where its a combination of wind and surge

[meteorologyman]

The data we get from weather the better however I think one piece of information is missing for the viewers that are worried with a hurricane hitting there area. That is comparison! If people don't have anything to compare then they won't know how light or serious the threat is.
Here is a made up Hurricane

Hurricane Dane Cat 2 Hurricane winds 110 mph Direction NW Hurricane Watch for S Hubert North Carolina
Wave Surge is 20 ft
Elevation is 3 ft
Coastal Flood surge : 17 ft maximum (average impact 10 ft) (20ft -3 ft = 17 ft) Damage: Heavy This is the comparison now these people know there house will be under water. 17 ft Maximum is the state when the eye wall hits
Waves are expected to decrease 1 ft every 1/2 mile inland. Any body in 7 mile radius of beach needs to evacuate
Wind Damage: Medium
Rain flooding: medium-moderate

Another example
Hurricane Dane Cat 2 Hurricane winds 110 mph Direction NW Hurricane Watch for Corpus Christi Naval Air Station Texas
Wave Surge: 23 ft
Elevation: 20ft
Coastal flood surge: 3 ft maximum (23ft - 20 ft = 3ft) average 6 inches damage: light
Wind Damage:medium low line areas: heavy for major city tall building\towers
rain flooding: Moderate-Heavy (area has been dry for two years ground won't soak up the expected 12 inches of rain even though they are in 48 in drought (hypothetically speaking on severe drought issue).

[RobWESTPACWX]

I like the storm surge scale, problem is forecasting as some of you have already said. Personally and I know I'm going to regret saying this, is I like Japan's system, Typhoon or Super Typhoon. Someone here's Super they know to get out of the way. It demonstrates more of a urgent nature I suppose. Yet it is always more convenient to have a scale but getting to exact yet I think can also be mis-leading. For example the surge varies from spot to spot based on the coastline. And we all know of at least one case where the surge was higher than predicted.

I guess what I'm saying and this is just my opinion. To exact of a forecast can lead to false sense of security possibly. Thats all though, I would love to hear what someone of you think.

[Hurricane Andrew]

I wanna make my own.

The Hurricane Impact Scale

3 Categories. Wind, Surge, and Flooding

HIS Wind.
TD-<39 MPH
TS-39-73mph
Cat 1-74-95mph
Cat 2-96-110mph
Cat 3-111-130mph
Cat 4-131-155mph
Cat 5-155+mph

HIS Surge (Issued per county)
Alert 1 <4 feet
Alert 2 4-8 feet
Alert 3 8-14 feet
Alert 4 14-20 feet
Alert 5 20-25 feet
Alert 6 25 feet plus

HIS Flooding
Alert 1 Minor Flooding, mainly street and poor drainage
Alert 2 Some Flooding
Alert 3 Significant Flooding
Alert 4 Major flooding
Alert 5 Catastrophic Flooding

So a advisory header might look like this

Hurricane Daniel strengthens to a HIS 3. Impacts set at Surge: Alert 3 and Flooding: Alert 2

[Hurricane Andrew]

PS: Personally, I like the way the Saffir Simpson Wind Scale is now. They could just make a seperate "Surge Alert" thing for landfalls.

[euro6208]

I like the storm surge scale, problem is forecasting as some of you have already said. Personally and I know I'm going to regret saying this, is I like Japan's system, Typhoon or Super Typhoon. Someone here's Super they know to get out of the way. It demonstrates more of a urgent nature I suppose. Yet it is always more convenient to have a scale but getting to exact yet I think can also be mis-leading. For example the surge varies from spot to spot based on the coastline. And we all know of at least one case where the surge was higher than predicted.

I guess what I'm saying and this is just my opinion. To exact of a forecast can lead to false sense of security possibly. Thats all though, I would love to hear what someone of you think.

Japan doesn't use Super Typhoon, only Jtwc does...

Super Typhoon is 1 minute winds of 130 knots which Jtwc uses like NHC. Japan uses 10 minute...

[Hurricane Jed]

Flooding is too hard to predict. While most tropical cyclones are capable of providing flooding rains to various degrees, its impossible to tell how much rainfall one will drop. Rainfall is dependent on how fast the storm is moving and how much moisture the storm contains. I mean you could say hey Tropical Storm Earl is going to drop 7 inches in some places but what if it merges with another system unexpectedly drops 30 inches or stalls over particular area because of weak steering currents.

[SouthDadeFish]

Honestly with the computer models we have now, they can make pretty accurate forecasts of how much rainfall a storm will bring. Usually storms don't merge "unexpectedly" with another system. The hard part is forecasting where the rainfall will occur, but yeah I see what you're saying.

[Hurricane Jed]

Yeah I've seen the models, but we often receive a lot less rain than they project or it doesn't rain hard up above us to cause significant flooding. I can't remember how much rain TS Hermine was projected to drop but we got over 16 inches in G'town and I know I didn't expect that much rain. I know if it rains hard in G'town the San Gabriel Rivers will flood some. But if it rains hard up above us in Burnet and in G'town like it did during Hermine, then the flooding will be pretty bad. I think the key for flooding is for people to know how their particular area will flood and if it is dependent on certain other factors like raining at a higher elevation above their town or residence.

[lester]

NOAA NWS National Hurricane Center
The Saffir-Simpson Hurricane Wind Scale is undergoing a minor modification for 2012 in order to resolve awkwardness with the conversions among the various units used for wind speed in advisory products. The change broadens the Category 4 wind speed range by one mile per hour (mph) at each end of the range, yielding a new range of 130-156 mph. This change does not alter the category assignments of any storms in the historical record, nor will it change the category assignments for future storms. For more information, please see: http://www.nhc.noaa.gov/aboutsshws.php

[bg1]

The category assignments for historical storms will not change, however, 115 kts- the minimum for a Category 4- will be rounded correctly to 130 mph now instead of 135 mph. Therefore, they had to restructure the scale to make 130 mph part of the Category 4 winds. The same goes for the upper scale and kilometers per hour.

[Blown Away]

Something cool about the way Cat 6 sounds, I like that idea!!!

[P.K.]

I like the storm surge scale, problem is forecasting as some of you have already said. Personally and I know I'm going to regret saying this, is I like Japan's system, Typhoon or Super Typhoon. Someone here's Super they know to get out of the way. It demonstrates more of a urgent nature I suppose.

The JMA are similar to most of the other RSMCs with 2 categories of TSs and 3 categories from 64kts. I do like their scale. The advantage is people take more notice rather than only paying attention to the higher end of the scale as you are already up to category 3 out of 5 by the time you get 64kt winds.

So this gives you something like

34-47kts Moderate TS
48-63kts Severe TS
64-85kts Cat 1
86-106kts Cat 2
107kts + Cat 3

The above is in ten min winds before anyone asks.

[P.K.]

Japan doesn't use Super Typhoon, only Jtwc does...

Super Typhoon is 1 minute winds of 130 knots which Jtwc uses like NHC. Japan uses 10 minute...

Not true. The CMA and HKO also use it. All three have different definitions though. What matters is that the RSMC doesn't use it as you correctly point out.