Hurricane Idalia

[bigtenfan]

Looking somewhat further ahead:  Some of this morning long range guidance has storm  this doing a full loop once off shore and circling around to be a threat to the SE coast of Florida. Are the steering currents that crazy for that to be a reasonable possibility?

[WxWatcher007]

Center dropsonde. Pressure probably down to about 977mb. 

 

Product: NOAA Temp Drop (Dropsonde) Message (UZNT13 KWBC)
Transmitted: 29th day of the month at 11:38Z
Agency: National Oceanic and Atmospheric Administration (NOAA)
Aircraft: Lockheed WP-3D Orion (Reg. Num. N43RF)
Storm Name: Idalia
Storm Number: 10 (flight in the North Atlantic basin)
Mission Number: 10
Observation Number: 05

Part A...
 

Date: Near the closest hour of 11Z on the 29th day of the month
Highest Mandatory Level For Which Wind Was Reported: 850mb
Coordinates: 23.7N 84.7W
Location: 154 statute miles (247 km) to the WNW (285°) from Havana, Cuba.
Marsden Square: 081 ( About )
 

Surface and Standard Isobaric Surfaces
Level	Geo. Height	Air Temp.	Dew Point	Wind Direction	Wind Speed
1000mb	-193m (-633 ft)	This level does not exist in this area of the storm above the surface level.
979mb (28.91 inHg)	Surface (Sea Level)	29.6°C (85.3°F)	27.4°C (81°F)	235° (from the SW)	20 knots (23 mph)
925mb	504m (1,654 ft)	25.6°C (78.1°F)	24.6°C (76°F)	245° (from the WSW)	23 knots (26 mph)
850mb	1,249m (4,098 ft)	24.0°C (75.2°F)	19.8°C (68°F)	240° (from the WSW)	20 knots (23 mph)
700mb	2,932m (9,619 ft)	16.4°C (61.5°F)	12.9°C (55°F)	No Wind Report Available For This Level

Information About Radiosonde:
- Launch Time: 11:27Z
- About Sonde: A descending radiosonde tracked automatically by satellite navigation with no solar or infrared correction.

Remarks Section...
 

Dropsonde Location: Dropped in center.

Highest altitude where wind was reported:
- Location: 23.72N 84.74W
- Time: 11:27:26Z

Lowest altitude where wind was reported:
- Location: 23.72N 84.72W
- Time: 11:31:33Z

Mean Boundary Level Wind (mean wind in the lowest 500 geopotential meters of the sounding):
- Wind Direction: 250° (from the WSW)
- Wind Speed: 24 knots (28 mph)

Deep Layer Mean Wind (average wind over the depth of the sounding):
- Wind Direction: 255° (from the WSW)
- Wind Speed: 17 knots (20 mph)
- Depth of Sounding: From 706mb to 978mb

Average Wind Over Lowest Available 150 geopotential meters (gpm) of the sounding:
- Lowest 150m: 155 gpm - 5 gpm (509 geo. feet - 16 geo. feet)
- Wind Direction: 250° (from the WSW)
- Wind Speed: 24 knots (28 mph)

Sounding Software Version: AEV 30409
 

Part B: Data for Significant Levels...
 

Significant Temperature And Relative Humidity Levels
Level	Air Temperature	Dew Point
979mb (Surface)	29.6°C (85.3°F)	27.4°C (81°F)
908mb	24.4°C (75.9°F)	24.0°C (75°F)
850mb	24.0°C (75.2°F)	19.8°C (68°F)
796mb	22.2°C (72.0°F)	About 17°C (63°F)
727mb	17.2°C (63.0°F)	15.6°C (60°F)
699mb	16.4°C (61.5°F)	12.7°C (55°F)

 

Significant Wind Levels
Level	Wind Direction	Wind Speed
979mb (Surface)	235° (from the SW)	20 knots (23 mph)
968mb	250° (from the WSW)	25 knots (29 mph)
850mb	240° (from the WSW)	20 knots (23 mph)
791mb	260° (from the W)	11 knots (13 mph)
743mb	310° (from the NW)	11 knots (13 mph)
706mb	300° (from the WNW)	7 knots (8 mph)

[WxWatcher007]

7:00 AM CDT Tue Aug 29
Location: 23.8°N 84.8°W
Moving: N at 14 mph
Min pressure: 977 mb
Max sustained: 80 mph
 

[SolidIcewx]

Looking strong so far. Can see more new convection wrapping around. The train is moving so to speak 

[WxWatcher007]

First VDM confirms the presence of an eye

 

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 29th day of the month at 11:57Z
Agency: National Oceanic and Atmospheric Administration (NOAA)
Aircraft: Lockheed WP-3D Orion (Reg. Num. N43RF)
Storm Name: Idalia
Storm Number & Year: 10 in 2023 (flight in the North Atlantic basin)
Mission Number: 10
Observation Number: 08 ( See all messages of this type for this mission. )

A. Time of Center Fix: 29th day of the month at 11:27:00Z
B. Center Fix Coordinates: 23.73N 84.75W
B. Center Fix Location: 157 statute miles (253 km) to the WNW (286°) from Havana, Cuba.
C. Minimum Height at Standard Level: 2,931m (9,616ft) at 700mb
D. Minimum Sea Level Pressure: 979mb (28.91 inHg)
E. Dropsonde Surface Wind at Center: From 235° at 20kts (From the SW at 23mph)
F. Eye Character: Spiral Band
G. Eye Shape & Diameter: Circular with a diameter of 20 nautical miles (23 statute miles)
H. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 63kts (72.5mph)
I. Location & Time of the Estimated Maximum Surface Wind Inbound: 10 nautical miles (12 statute miles) to the NNW (343°) of center fix at 11:24:36Z
J. Maximum Flight Level Wind Inbound: From 93° at 46kts (From the E at 52.9mph)
K. Location & Time of the Maximum Flight Level Wind Inbound: 12 nautical miles (14 statute miles) to the NNW (344°) of center fix at 11:23:56Z
L. Estimated (by SFMR or visually) Maximum Surface Wind Outbound: 62kts (71.3mph)
M. Location & Time of the Estimated Maximum Surface Wind Outbound: 12 nautical miles (14 statute miles) to the S (178°) of center fix at 11:29:54Z
N. Maximum Flight Level Wind Outbound: From 270° at 58kts (From the W at 66.7mph)
O. Location & Time of the Maximum Flight Level Wind Outbound: 18 nautical miles (21 statute miles) to the S (178°) of center fix at 11:31:09Z
P. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 15°C (59°F) at a pressure alt. of 3,060m (10,039ft)
Q. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 3,070m (10,072ft)
R. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°F)
R. Sea Surface Temp (collected at same location as temp inside eye): Not Available
S. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
S. Fix Level: 700mb
T. Navigational Fix Accuracy: 0.01 nautical miles
T. Meteorological Accuracy: 2 nautical miles

Remarks Section:
 

Maximum Flight Level Wind: 58kts (~ 66.7mph) which was observed 18 nautical miles (21 statute miles) to the S (178°) from the flight level center at 11:31:09Z

[40/70 Benchmark]

1 hour ago, WxWatcher007 said:

Didn't add to the post, but recent microwave imagery suggests a nearly completed eyewall. 

Def. gonna be using some of your images for my Final thoughts on this for the sake of time, if you don't mind....

[Brian5671]

12 minutes ago, bigtenfan said:

Looking somewhat further ahead:  Some of this morning long range guidance has storm  this doing a full loop once off shore and circling around to be a threat to the SE coast of Florida. Are the steering currents that crazy for that to be a reasonable possibility?

Would be a shell of its former self by then

[CoastalWx]

27 minutes ago, 40/70 Benchmark said:

Nice post. Only two issues with my thoughts from late Sunday/early Monday is that I rushed the RI by about 12 hours by underplaying the initial shear a bit, and probably need to adjust west a tad.

It’s still got some kinks to work out. I’d say later today and tonight is the opportunity to take off. 

[40/70 Benchmark]

Just now, CoastalWx said:

It’s still got some kinks to work out. I’d say later today and tonight is the opportunity to take off. 

Yea, my time-table was off by about 12-24 hours...I shouldn't have dismissed that initial shear, but I am not sure that is a good thing for the coast when all is said and done.

[WxWatcher007]

6 minutes ago, CoastalWx said:

It’s still got some kinks to work out. I’d say later today and tonight is the opportunity to take off. 

Yeah, it really doesn’t take off until this afternoon on the hurricane guidance, and it’s a 120kt storm on HAFS A & B.

[cardinalland]

lots of storms have been intensifying up to landfall recently and the northeast GOM is quite hot/above normal unfortunately

[CoastalWx]

10 minutes ago, 40/70 Benchmark said:

Yea, my time-table was off by about 12-24 hours...I shouldn't have dismissed that initial shear, but I am not sure that is a good thing for the coast when all is said and done.

Right. If it’s intensifying right until landfall that allows the strongest winds to mix down.

[40/70 Benchmark]

2 minutes ago, CoastalWx said:

Right. If it’s intensifying right until landfall that allows the strongest winds to mix down.

Yes....also less time for ERC...the only positive is that it won't be a worst case for surge, as ERCs are a vehicle for growth. Later intensification also means less time to pile water. This is potentially a worst case for wind, not surge.

[40/70 Benchmark]

I expect the worst damage to be fairly concentrated near and just to the east of LF.

[schoeppeya]

Looking at radar it looks like we are about to have our first fully closed eye shortly.

[SnowBeau]

The 5AM NHC forecast didn’t have Idalia hitting 84.8W until 5PM, yet it’s already there at 8AM.  Just a wobble, or is that significant?

[beanskip]

6 minutes ago, SnowBeau said:

The 5AM NHC forecast didn’t have Idalia hitting 84.8W until 5PM, yet it’s already there at 8AM.  Just a wobble, or is that significant?

If you look at the track of the HAFS it actually has a bit of a bend in it -- starts at 84.7 then gets all the way out to 85.5 before turning back. Not saying that's right, but will be interesting to see if a westerly component materializes. 

[cptcatz]

SE eye dropsonde recorded 63 kt at the surface with max flight level wind of 65 kt.  Where is NHC getting 80 mph from?  Seems like even calling it a hurricane is a stretch based on measured winds.

[WxWatcher007]

 

Just now, cptcatz said:

SE eye dropsonde recorded 63 kt at the surface with max flight level wind of 65 kt.  Where is NHC getting 80 mph from?  Seems like even calling it a hurricane is a stretch based on measured winds.

I think it’s a hurricane, but the winds on recon haven’t been that impressive. Yet. 

[beanskip]

6z Euro moves just enough west to be a killer for Apalachee Bay. Looks like a hit around the Jefferson/Taylor line based on Tidbits maps, but if someone has  more detail, that would be appreciated.

This also is close enough to Tallahassee that hurricane force winds will surely impact the capital city -- you can't even believe how many trees will come down. 

[schoeppeya]

To me, it looks like Idalia still doesn’t have most of its energy focused around the eyewall and think we need to see that bigger outer band really contract before we see winds increase and pressures start dropping. All the feeder bands are currently working into this band rather than the inner eyewall.

[jerseyshorewxguy]

My son is at Florida State and they have been very good with the updates---he lived through Hurricane Sandy and 17 days without power -- hopefully the power outages aren't that bad.  St Mark's nature preserve is going to get hammered.

[Radtechwxman]

Dr. Greg Kostel on TWC just said they're flying in there now and finding steady pressures. Something is holding Idalia back right now. It's over the Loop Current for the next 12hrs or so where the highest OHC is. If the rapid intensification doesn't occur then, then the lower end of guidance probably going to verify with a strong cat 2 borderline cat 3. Regardless, still going to be a problem where it landfalls with storm surge and obviously destructive winds. 

[Seminole]

25 minutes ago, beanskip said:

6z Euro moves just enough west to be a killer for Apalachee Bay. Looks like a hit around the Jefferson/Taylor line based on Tidbits maps, but if someone has  more detail, that would be appreciated.

This also is close enough to Tallahassee that hurricane force winds will surely impact the capital city -- you can't even believe how many trees will come down. 

I have seen pictures of Killearn Estates after Hurricane Kate in 1985 and the roads were impassable. Oak tree after oak tree across the roads. Hemine, Irma and Michael were child's play compared to what Kate did to Tallahassee. 

[ROOSTA]

For posterity and humanity..."BRIGHTO"

[WxWatcher007]

There’s your 69-70kt SFMR.

[so_whats_happening]

21 minutes ago, StormChaser4Life said:

Dr. Greg Kostel on TWC just said they're flying in there now and finding steady pressures. Something is holding Idalia back right now. It's over the Loop Current for the next 12hrs or so where the highest OHC is. If the rapid intensification doesn't occur then, then the lower end of guidance probably going to verify with a strong cat 2 borderline cat 3. Regardless, still going to be a problem where it landfalls with storm surge and obviously destructive winds. 

This is definitely a reasonable take structure doesn't seem fully stacked yet. Forward speed may be hindering it a bit since it can't get it structure setup? 3 seems to be the upper limit at this point unless we get heck of a surprise. Definitely trying its best to get organized quick though.

[Covidea]

 

23 minutes ago, StormChaser4Life said:

Dr. Greg Kostel on TWC just said they're flying in there now and finding steady pressures. Something is holding Idalia back right now. It's over the Loop Current for the next 12hrs or so where the highest OHC is. If the rapid intensification doesn't occur then, then the lower end of guidance probably going to verify with a strong cat 2 borderline cat 3. Regardless, still going to be a problem where it landfalls with storm surge and obviously destructive winds. 

Yep - They're in there now.

[so_whats_happening]

It is worrisome though that a rather large eye could open up rather quickly this afternoon into the evening during what is usually a nice uptick in thunderstorm activity. 

[hawkeye_wx]

The third recon pass this morning is also 978 mb, so Idalia remains in a holding pattern.  Landfall is only 24 hours away, so it will really need to step on the gas later today.