Hurricane Idalia

[biodhokie]

5 minutes ago, WxWatcher007 said:

Yeah, I was out of the loop  

[WxWatcher007]

Well the ensemble guidance is split and the hurricane track models to loop it. It probably is a shell of itself if it happens before a trough kicks it.

[NorthHillsWx]

34 minutes ago, WxWatcher007 said:

Well the ensemble guidance is split and the hurricane track models to loop it. It probably is a shell of itself if it happens before a trough kicks it.

Likely a convection less low level swirl if it gets left behind. If it’s generating deep convection it’s going to exit stage right 

[Eskimo Joe]

 

 

[HiltonHeadWx]

15 hours ago, RU848789 said:

Question for you.  In theory, wind gusts greater than 65 mph are usually needed to uproot mature trees and there was a report of 30 trees down on HHI, so I assume then, that at least at times and maybe in isolated locations, winds probably gusted over 65 mph, even if those speeds weren't recorded at the few stations on the island.  So, was wondering what the max recorded gusts were on HHI (the public info statement from the NWS office doesn't show any gusts on HHI over 40 mph, unless I'm not aware of place names).  Any input on that?  

Edit: looking at the PNS for the area, there were gusts of 69 mph on Tybee Island about 7 miles SW of HHI, 66 mph in Beaufort about 10 miles NE of HHI and 64 mph in Calibogue Sound about 1-2 miles SW of HHI.  I just find it hard to believe that some places on HHI wouldn't have had 60+ mph gusts given reports of gusts that high surrounding the island, despite the reports of only ~35 mph gusts - looks more like the vagaries of wind variability and maybe instrument issues on HHI stations.  

https://forecast.weather.gov/product.php?site=NWS&issuedby=CHS&product=PNS&format=CI&version=1&glossary=1

https://www.wtoc.com/2023/08/31/not...island-residents-grateful-low-impacts-idalia/

https://www.weather.gov/media/pqr/wind/wind.pdf

It can frustrating getting good readings on Hilton Head Island, especially for wind. The airport does report data hourly, with the exception of precipitation, which for some odd reason it doesn’t measure. While it’s a small airport, it is heavily used by general aviation and American, Delta, and United have multiple commuter jet flights to major eastern and midwestern cities. The lack of a full reporting station there is a bit puzzling. That aside, yesterday the airport was offline, for some unknown reason, from 11AM until 9PM, thus completely missing the time period when winds were peaking on the island.  There are many amateur stations on the island, including mine, but few, if any, are able to get good wind readings due the heavily treed nature of Hilton Head.  I have a Davis station, but my anemometer is basically worthless due to my home being surrounded by tall pines, oaks, palms, etc. 

My semi-educated guess is the peak wind gusts did exceed 60mph, especially in areas of the island with southern exposure toward the ocean. At my home, I’d guess we didn’t exceed 50mph, but I’m toward the northern tip of HHI, with much more exposure to winds coming from the north or west off of Port Royal Sound and Skull Creek. After the storm, I only had a few large limbs in the yard, plus a good number of small branches and a lot of pine needles.  No tree damage and none visible anywhere around the neighborhood. We also never loss power, it didn’t even flicker, which is not too surprising considering the vast majority of power & communication lines on HHI are underground.  All in all, much of the island escaped pretty much unscathed by Idalia.

 

 

[GaWx]

2 hours ago, HiltonHeadWx said:

It can frustrating getting good readings on Hilton Head Island, especially for wind. The airport does report data hourly, with the exception of precipitation, which for some odd reason it doesn’t measure. While it’s a small airport, it is heavily used by general aviation and American, Delta, and United have multiple commuter jet flights to major eastern and midwestern cities. The lack of a full reporting station there is a bit puzzling. That aside, yesterday the airport was offline, for some unknown reason, from 11AM until 9PM, thus completely missing the time period when winds were peaking on the island.  There are many amateur stations on the island, including mine, but few, if any, are able to get good wind readings due the heavily treed nature of Hilton Head.  I have a Davis station, but my anemometer is basically worthless due to my home being surrounded by tall pines, oaks, palms, etc. 

My semi-educated guess is the peak wind gusts did exceed 60mph, especially in areas of the island with southern exposure toward the ocean. At my home, I’d guess we didn’t exceed 50mph, but I’m toward the northern tip of HHI, with much more exposure to winds coming from the north or west off of Port Royal Sound and Skull Creek. After the storm, I only had a few large limbs in the yard, plus a good number of small branches and a lot of pine needles.  No tree damage and none visible anywhere around the neighborhood. We also never loss power, it didn’t even flicker, which is not too surprising considering the vast majority of power & communication lines on HHI are underground.  All in all, much of the island escaped pretty much unscathed by Idalia.

 

 

PUBLIC INFORMATION STATEMENT   NATIONAL WEATHER SERVICE CHARLESTON SC   1209 AM EDT THU AUG 31 2023       ..HIGHEST WIND REPORTS FROM IDALIA       LOCATION SPEED TIME/DATE PROVIDER

  SOUTH TYBEE ISLAND 69 MPH 0439 PM 08/30 WXFLOW

BEAUFORT 66 MPH 0619 PM 08/30 WXFLOW  

CALIBOGUE SOUND 64 MPH 0536 PM 08/30 WXFLOW

Based on the above from NWS CHS, I'd think 60+ on parts of HH is supported. This data was pulled from here:

https://kamala.cod.edu/offs/KCHS/2308310409.nous42.html

[Eskimo Joe]

4 hours ago, HiltonHeadWx said:

It can frustrating getting good readings on Hilton Head Island, especially for wind. The airport does report data hourly, with the exception of precipitation, which for some odd reason it doesn’t measure. While it’s a small airport, it is heavily used by general aviation and American, Delta, and United have multiple commuter jet flights to major eastern and midwestern cities. The lack of a full reporting station there is a bit puzzling. That aside, yesterday the airport was offline, for some unknown reason, from 11AM until 9PM, thus completely missing the time period when winds were peaking on the island.  There are many amateur stations on the island, including mine, but few, if any, are able to get good wind readings due the heavily treed nature of Hilton Head.  I have a Davis station, but my anemometer is basically worthless due to my home being surrounded by tall pines, oaks, palms, etc. 

My semi-educated guess is the peak wind gusts did exceed 60mph, especially in areas of the island with southern exposure toward the ocean. At my home, I’d guess we didn’t exceed 50mph, but I’m toward the northern tip of HHI, with much more exposure to winds coming from the north or west off of Port Royal Sound and Skull Creek. After the storm, I only had a few large limbs in the yard, plus a good number of small branches and a lot of pine needles.  No tree damage and none visible anywhere around the neighborhood. We also never loss power, it didn’t even flicker, which is not too surprising considering the vast majority of power & communication lines on HHI are underground.  All in all, much of the island escaped pretty much unscathed by Idalia.

If you are referring to Hilton Head, KHXD, then the difficulties are possibly due to it being an AWOS and not ASOS. AWOS are antiquated systems that can be put at lower priority airports. If I recall correctly, AWOS do not have a mandate to be augmented by humans, not do they require an alternate power source. Therefore, if there is a commercial power loss the system just goes dark. We simply do not fund our environmental observation networks in the US and the truly upsetting part is that it would not cost too much money to do so.

[gymengineer]

A lot of focus was on the storm surge record at Cedar Key, but it looks like Steinhatchee also easily broke its record set by Hermine. And Clearwater Beach had its highest water level as well, breaking the record set by the 1993 Superstorm. St. Petersburg was really close to its record water level as well, ending up a close second. 

[GaWx]

2 hours ago, gymengineer said:

A lot of focus was on the storm surge record at Cedar Key, but it looks like Steinhatchee also easily broke its record set by Hermine. And Clearwater Beach had its highest water level as well, breaking the record set by the 1993 Superstorm. St. Petersburg was really close to its record water level as well, ending up a close second. 

Great point. Does anyone know what the official Tampa Bay storm surge was?

[WxWatcher007]

My video from the storm. Damage survey video tomorrow. 
 

[GaWx]

3 hours ago, GaWx said:

Great point. Does anyone know what the official Tampa Bay storm surge was?

Well, I looked at the site linked below and it appears that Tampa may have had a 5.2 ft storm surge at 8:12 AM on August 30th! If this were to verified as accurate, that may be the highest surge at least since the 5 ft from Gladys of 1968! That's pretty amazing considering how far offshore it was and that it landfalled way up in the Big Bend!

 Can anyone verify this data?

https://tidesandcurrents.noaa.gov/waterlevels.html?id=8726607&bdate=20230829&edate=20230831&units=standard&timezone=GMT&interval=6

 

[traindog71]

Most record surge is measured over MHHW, not just over the expected tide at a given time.


.

[KPITSnow]

Early estimates of 20 billion in damage, so for those complaining it was t that bad, that makes it a top 15 storm I believe.

[NorthHillsWx]

5 minutes ago, KPITSnow said:

Early estimates of 20 billion in damage, so for those complaining it was t that bad, that makes it a top 15 storm I believe.

Where is the damage? Usually there are picture’s everywhere. Other than a few micro communities and Perry I do not see where this value comes from. In NC where I live there was some flooding down east but nothing you wouldn’t expect from any tropical system. Maybe crop damage jacked it up? I just do not see 20 billion in damage from anything I’ve seen so far 

[GaWx]

6 hours ago, traindog71 said:

Most record surge is measured over MHHW, not just over the expected tide at a given time.


.

 I'm trying to understand the terminology better. At 12:12Z on 8/30, the linked graph for Tampa shows a 6.64 foot tide (red line) that appears to be using MLLW as a reference. It also shows a 1.433 predicted (blue line, which is the astronomical) tide then. In addition, when one clicks on "observed - predicted", it then displays a purple line that was at its max of 5.21 feet at 12:12Z. That's 6.64 ft minus 1.433 ft.

 So, that appears to be the maximum extra water level caused by the storm. Are you saying that the maximum "observed - predicted" is not the storm surge? If not, what is that called?

https://tidesandcurrents.noaa.gov/waterlevels.html?id=8726607&bdate=20230829&edate=20230831&units=standard&timezone=GMT&interval=6

[CoastalWx]

5 hours ago, NorthHillsWx said:

Where is the damage? Usually there are picture’s everywhere. Other than a few micro communities and Perry I do not see where this value comes from. In NC where I live there was some flooding down east but nothing you wouldn’t expect from any tropical system. Maybe crop damage jacked it up? I just do not see 20 billion in damage from anything I’ve seen so far 

A lot of it probably is from water. Either freshwater or salt water. It's pretty easy to rack up large losses these days with the price of real estate.

[LongBeachSurfFreak]

47 minutes ago, CoastalWx said:

A lot of it probably is from water. Either freshwater or salt water. It's pretty easy to rack up large losses there days with the price of real estate.

I agree. Surge flooding in places like the Tampa area. Not news worthy because who cares if someone got 6” of water in their house but, for that owner that could mean 10,000%+ of ripping out carpets/floors. We have seen it so many times on the south shore of Long Island. (Not mentioning the S word) 

[NorthHillsWx]

7 hours ago, CoastalWx said:

A lot of it probably is from water. Either freshwater or salt water. It's pretty easy to rack up large losses these days with the price of real estate.

I know I just have friends in Tampa and work for the utility company that covers NC, SC, and Fl. It was extremely underwhelming for us (good thing) but 20 billion is extreme and there didn’t seem to be extreme damage but in areas no one lived. My point I guess is if this is the case a cat 1 hitting Tampa would also be a 20 billion $ disaster 

[NorthHillsWx]

As expected, loss estimates from Idalia have come way down. While some early estimates placed damage at nearly 20 billion, estimates have fallen to a more paltry number of 3-5 billion

https://www.reuters.com/markets/us/private-market-insured-losses-hurricane-idalia-be-3-5-bln-moodys-rms-2023-09-04/