Major Hurricane Danielle

[Iceberg]

A new update just released from NHC

Danielle is now a officially a powerful CAT 4 at 115kts and is still due to strengthen.

It's likely that we will start to look for ERC's now.

ESTIMATED MINIMUM CENTRAL PRESSURE 946 MB

EYE DIAMETER 15 NM

MAX SUSTAINED WINDS 115 KT WITH GUSTS TO 140 KT.

64 KT....... 50NE 40SE 30SW 45NW.

50 KT....... 90NE 60SE 60SW 90NW.

34 KT.......180NE 120SE 105SW 135NW.

12 FT SEAS..330NE 270SE 250SW 240NW.

WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL

MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 26.5N 58.7W AT 27/0900Z

AT 27/0600Z CENTER WAS LOCATED NEAR 26.2N 58.3W

FORECAST VALID 27/1800Z 27.5N 60.0W

MAX WIND 115 KT...GUSTS 140 KT.

64 KT... 55NE 45SE 40SW 50NW.

50 KT... 95NE 70SE 70SW 90NW.

34 KT...180NE 130SE 120SW 140NW.

FORECAST VALID 28/0600Z 28.9N 60.9W

MAX WIND 120 KT...GUSTS 145 KT.

64 KT... 55NE 50SE 45SW 50NW.

50 KT...100NE 75SE 70SW 90NW.

34 KT...180NE 150SE 130SW 140NW.

[Iceberg]

DANIELLE HAS CONTINUED TO INTENSIFY OVERNIGHT...WITH INFRARED

IMAGERY SHOWING A DISTINCT WARM EYE SURROUNDED BY A RING OF VERY

COLD CLOUD TOPS. BASED ON THE TAFB DVORAK ESTIMATE AND CURRENT ADT

VALUES AROUND 6.0...THE INITIAL INTENSITY IS SET AT 115 KT. LOW

SHEAR CONDITIONS APPEAR FAVORABLE FOR SOME ADDITIONAL STRENGTHENING

OVER THE NEXT DAY OR SO...AND THE OFFICIAL FORECAST HAS BEEN

ADJUSTED UPWARD TO SHOW A PEAK AT 120 KT IN ABOUT 24 HOURS...IN

BEST AGREEMENT WITH THE SHIPS MODEL. THE SHEAR WILL BEGIN TO

INCREASE AROUND 36 HOURS...AND A SLOW WEAKENING IS EXPECTED TO

BEGIN AROUND THAT TIME. A FURTHER INCREASE IN SHEAR COMBINED WITH

COOLER WATERS AND A MORE STABLE ATMOSPHERE WILL RESULT IN MORE

SUBSTANTIAL WEAKENING BY DAYS 3 AND 4. BY DAY 5...BOTH THE GFS AND

ECMWF SHOW DANIELLE MAINTAINING HURRICANE INTENSITY AS THE CYCLONE

BEGINS TO UNDERGO EXTRATROPICAL TRANSITION.

[peterf]

great thread this folks,keep up the good work.

has there been any flights over her yet?peter

[Iceberg]

Thanks Peter, recon will be later this afternoon for the first ever time into Danielle and I will certaintly try to update the thread as it comes in, the initial pass will be very interesting. !

[peterf]

cheers iceberg its addictive watching this unfold lol.

[Gray-Wolf]

My what a beautiful young lady she became!!!

So Cat 5 the next stop?

[Iceberg]

My what a beautiful young lady she became!!!

So Cat 5 the next stop?

Even more beautiful with some daylight, fantastic hurricane, also a close up of the eye, where the bubbly Thunderstorms can be seen and the almost shear drop to the sea from a height of 80K ft, the eye is certainly closed and intensification is still very much ongoing.

At a rough estimate I would say that Danielle is currently 120-125kts, only a few more hrs until recon.

Maybe a guessing game to see what the max flight winds are, given that the flight winds are generally 15-20% greater than the surface winds which are offically 115kts I think we can expect something between 135kts to 160kts flight winds

Personally atm I would go for 145kts, with a large hurricane wind field.

A few other things we can test with recon.

ATM NHC are going with hurricane winds 60 miles from the centre and Tropical storm winds 200 miles from the centre and a minimum pressure of 946mb (likely dropped to 938-940mb by the time recon get in).

At the moment NHC are predicting wind gusts upto 167mph within the eye wall in the next 24 hrs.

[Iceberg]

Forgot to mention wrt track Danielle is not playing ball yet, it is still going only slightly north of due west, NHC have expected a sharp turn northwards at this time due to an established ridge weakness.

This could be just a wobble westwards caused by the intensification, however it needs to turn north in the next few hrs, otherwise Bermuda suddenly starts to look rather vunerable, particularly given the large wind field.

It's worth looking at the loops as per the link below with the Trop pts box ticked

http://www.ssd.noaa.gov/goes/flt/t1/loop-avn.html

[Gray-Wolf]

Well we're used to them not playing ball but this could have a knock on effect for Earl and the next two (if all are still 'influencing' the patterns across the Atlantic).

If Danielle does become an issue for Bermuda then her remnants may become an issue for the Eastern seaboard of the U.S.?

[Iceberg]

Recon have taken off and are on their way. !

Won't be long now before the real state of Danielle is known, they are flying up from the SW so it shouldn't take too long maybe 1 to 2 hrs.

[Paranoid]

It's possible that Danielle could start to weaken a little from here onwards, as we haven't seen an eyewall replacement yet and that usually occurs in intense storms like this. That said, i havent seen anything on the satellite loops that would suggest that.

[Iceberg]

I agree she's due to take a pause now after a busy 24 hrs, the latest sat does show the eye slightly more ragged than it has been for the last few hours. An estimate is 16.00 to 16.15 our time for recon to start to get proper readings so she needs to hang on for a little longer....please.....

[Paranoid]

Has anyone got the recon data? That usually gets posted at some point but i dont know where the one for Danielle is.

[Iceberg]

It't coming in on the USAF here.

http://www.nhc.noaa.gov/text/URNT15-USAF.shtml?

[Paranoid]

No change in strength so far but this may be pending the results of the recon

000

WTNT31 KNHC 271453

TCPAT1

BULLETIN

HURRICANE DANIELLE ADVISORY NUMBER 25

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062010

1100 AM AST FRI AUG 27 2010

...DANIELLE STILL A CATEGORY FOUR HURRICANE...

SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION

-----------------------------------------------

LOCATION...26.9N 59.8W

ABOUT 480 MI...770 KM SE OF BERMUDA

MAXIMUM SUSTAINED WINDS...135 MPH...215 KM/HR

PRESENT MOVEMENT...NW OR 305 DEGREES AT 12 MPH...19 KM/HR

MINIMUM CENTRAL PRESSURE...946 MB...27.94 INCHES

WATCHES AND WARNINGS

--------------------

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

INTERESTS IN BERMUDA SHOULD MONITOR THE PROGRESS OF DANIELLE.

DISCUSSION AND 48-HOUR OUTLOOK

------------------------------

AT 1100 AM AST...1500 UTC...THE CENTER OF HURRICANE DANIELLE WAS

LOCATED NEAR LATITUDE 26.9 NORTH...LONGITUDE 59.8 WEST. DANIELLE IS

MOVING TOWARD THE NORTHWEST NEAR 12 MPH...19 KM/HR. A TURN TOWARD

THE NORTH-NORTHWEST IS EXPECTED BY TONIGHT FOLLOWED BY A

TURN TOWARD THE NORTH ON SATURDAY. ON THE FORECAST TRACK...THE

CENTER OF DANIELLE IS EXPECTED TO PASS WELL TO THE EAST OF BERMUDA

SATURDAY NIGHT.

MAXIMUM SUSTAINED WINDS REMAIN NEAR 135 MPH...215 KM/HR...WITH

HIGHER GUSTS. DANIELLE IS A CATEGORY FOUR HURRICANE ON THE

SAFFIR-SIMPSON HURRICANE WIND SCALE. SOME SLIGHT STRENGTHENING IS

POSSIBLE DURING THE NEXT 24 HOURS. AN AIR FORCE RESERVE UNIT

RECONNAISSANCE UNIT AIRCRAFT SCHEDULED TO INVESTIGATE DANIELLE THIS

AFTERNOON WILL PROVIDE A BETTER ESTIMATE OF THE EXACT STRENGTH OF

THE HURRICANE.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM

THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 205

MILES...335 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 946 MB...27.94 INCHES.

HAZARDS AFFECTING LAND

----------------------

SURF...LARGE WAVES AND DANGEROUS SURF CONDITIONS WILL AFFECT BERMUDA

OVER THE NEXT FEW DAYS. SWELLS FROM DANIELLE WILL BEGIN TO ARRIVE

ON THE EAST COAST OF THE UNITED STATES ON SATURDAY. THESE SWELLS

ARE LIKELY TO CAUSE DANGEROUS RIP CURRENTS THROUGH THE WEEKEND.

PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL WEATHER OFFICE.

NEXT ADVISORY

-------------

NEXT COMPLETE ADVISORY...500 PM AST.

$$

FORECASTER STEWART

[Iceberg]

Recon has entered the SW outflow of Danielle...... (just to build any suspense their might be)

[Iceberg]

First Tropical storm winds recorded at 25.383N 62.033W (approx 100 miles from the centre).

Starting to get into Danielle proper now, pressure down to 1006mb winds of 40-45kts consistantly being recorded, hurricane winds should be seen in the next update in 10 mins, but we are still quite away from the centre.

AF305 0106A DANIELLE HDOB 12 20100827

150430 2530N 06159W 4692 06345 0308 -078 -094 305020 021 030 002 00

150500 2532N 06157W 4891 06027 0292 -059 -072 318022 022 031 001 03

150530 2533N 06156W 5110 05685 0269 -042 -050 333024 025 /// /// 03

150600 2535N 06155W 5369 05284 0240 -023 -029 338027 028 /// /// 03

150630 2537N 06154W 5673 04841 0044 -000 -007 331025 026 /// /// 03

150700 2540N 06153W 5980 04400 0051 +020 +012 336026 027 /// /// 03

150730 2542N 06151W 6277 04034 0075 +042 +024 345031 033 /// /// 03

150800 2544N 06150W 6574 03656 0072 +063 +040 349036 039 /// /// 03

150830 2545N 06149W 6793 03379 0069 +080 +072 352040 040 034 000 03

150900 2547N 06148W 6926 03221 0071 +089 +072 355043 044 033 001 00

150930 2549N 06147W 6976 03163 0075 +091 +073 354041 041 034 000 00

151000 2550N 06146W 6963 03174 0071 +088 +084 349039 040 034 002 00

151030 2551N 06146W 6965 03174 0073 +089 +083 349040 040 036 001 00

151100 2552N 06145W 6969 03167 0071 +090 +082 349040 041 036 002 00

151130 2554N 06144W 6966 03169 0064 +093 +079 350043 043 036 002 00

151200 2555N 06143W 6967 03165 0060 +095 +076 352042 043 035 003 00

151230 2556N 06142W 6970 03159 0065 +089 +076 349043 044 035 004 00

151300 2558N 06142W 6964 03168 0064 +090 //// 346042 043 037 006 05

151330 2559N 06140W 6966 03162 //// +078 //// 340039 041 040 014 01

151400 2600N 06139W 6964 03152 //// +072 //// 336041 047 045 024 01

[Iceberg]

Flight winds of 58 kts, pressure at 1001.5mb so still nowhere near the centre which is say 940mb

152200 2618N 06118W 6947 03152 //// +075 //// 337049 055 057 032 05

152230 2619N 06116W 6987 03111 //// +075 //// 339053 058 052 015 05

152300 2620N 06115W 6963 03133 //// +076 //// 334048 048 050 014 01

152330 2621N 06114W 6967 03130 0020 +090 //// 346044 044 044 003 01

152400 2622N 06113W 6967 03128 0015 +094 //// 348044 046 041 003 01

[Paranoid]

Which coloumn on there is the pressure reading? I used to know this but it's been a while since i last looked at one of these.

Just noticed on the visible satellite run that there appears to be a stadium effect within the eye, so Danielle could still be intensifying while recon are in there.

Will the recon data be ued for an intermidiate advisory or the 10pm advisory?

[Iceberg]

Column 6 is pressure, If they find something which is substantially different to the current thinking i.e 940 and 115kts then they will issue an update I think , if not it will wait until the next advisory.

The last lot of readings took pressure to sub 999mb(gradually) with sustained winds of 40-50kts.

Flight level winds to 76kts now, pressure at 979mb and sustained winds of just about hurricane strength.

This will be the weakest of the 4 quads though.

What's most interesting so far is that large pressure area of sub 990mb, this is indicative of a large hurricane which will take awhile to go up and down.

153900 2645N 06026W 6970 03022 9878 +113 +102 000059 060 054 002 00

153930 2645N 06025W 6969 03018 9875 +110 +109 360061 062 054 006 00

154000 2646N 06023W 6969 03009 9872 +105 //// 359061 062 054 008 01

154030 2646N 06022W 6969 03004 9870 +102 //// 358061 062 056 008 01

154100 2647N 06020W 6970 02995 9856 +107 //// 357063 064 057 008 01

154130 2648N 06019W 6963 02994 9847 +107 //// 358066 067 059 006 01

154200 2648N 06017W 6970 02979 9833 +113 +106 358068 069 059 005 00

154230 2648N 06017W 6970 02979 9814 +119 +109 358071 072 061 006 00

154300 2649N 06014W 6969 02959 9800 +120 +113 359072 073 063 008 03

154330 2650N 06012W 6965 02953 9794 +113 //// 000073 074 064 010 01

154400 2650N 06011W 6967 02934 //// +101 //// 358073 076 067 018 01

[Iceberg]

Well we have our first pass of the centre and it's quite a surprise.

Minimum pressure of 942mb and flight winds of only 118kts equate to a CAT 3 at around 100-105kts.

Based on this we might need a downgrade.

What we do need are another pass and the vortex data (going home now)

154430 2651N 06009W 6964 02921 //// +095 //// 357076 078 071 016 01

154500 2651N 06007W 6967 02897 //// +095 //// 360077 079 071 010 01

154530 2651N 06006W 6963 02881 9705 +114 //// 358084 087 074 016 01

154600 2652N 06004W 6972 02839 9696 +099 //// 358089 091 079 023 01

154630 2652N 06002W 6965 02812 //// +094 //// 356097 099 086 037 01

154700 2652N 06001W 6969 02750 //// +105 //// 351099 102 097 028 01

154730 2652N 05959W 6951 02730 9483 +133 //// 350071 081 095 011 05

154800 2653N 05957W 6976 02676 9449 +171 +135 355034 048 060 003 03

154830 2653N 05955W 6966 02681 9442 +176 +111 006020 022 034 002 03

154900 2653N 05953W 6966 02675 9437 +177 +099 358013 015 024 001 03

154930 2653N 05951W 6971 02669 9438 +174 +099 033001 005 024 002 03

155000 2654N 05949W 6967 02669 9429 +182 +090 155011 015 025 002 00

155030 2654N 05947W 6969 02666 9427 +183 +088 168016 018 024 002 03

155100 2655N 05945W 6960 02674 9420 +182 +104 157024 029 039 003 03

155130 2656N 05944W 6971 02662 9442 +161 +138 149053 065 074 004 03

155200 2658N 05943W 6962 02703 9487 +144 //// 147087 097 091 003 01

155230 2659N 05941W 6951 02758 //// +106 //// 147113 118 092 009 01

155300 2700N 05940W 6970 02783 9621 +109 //// 146117 118 090 005 01

155330 2701N 05938W 6978 02815 9659 +116 //// 145109 112 083 005 01

155400 2703N 05937W 6959 02870 9702 +108 //// 143106 107 078 008 01

[Paranoid]

942mb would be lower than the current advisory suggests as they estimated 946mb. It's possible they overestimated the windspeeds as up until now they've been relying on satellite analysis and the Dvorak technique; this is the first time they've had anything human investigate it. Also depends on which side they approached the centre from, as i think this was from the southwest which is the weakest section of the storm. Once we've had a look at the northeast section that should give us a better idea of whether they overestimated the winds or not.

Edited August 27, 2010 by Paranoid

[Iceberg]

Editted to make sense. They are now doing another pass, that recon from earlier included the SW and NE quads so should be a pretty good indication.

Vortex below shows a very healthy temperature differential in the eye and a good closed eye, maybe winds are being slow to crank upto the pressure and eye due to the large wind field ?.

VORTEX DATA MESSAGE AL062010

A. 27/15:49:40Z

B. 26 deg 53 min N

059 deg 51 min W

C. 700 mb 2632 m

D. 96 kt

E. 263 deg 8 nm

F. 353 deg 102 kt

G. 263 deg 9 nm

H. 945 mb

I. 9 C / 3040 m

J. 19 C / 3053 m

K. 12 C / NA

L. CLOSED WALL

M. C18

N. 12345 / 7

O. 0.02 / 1 nm

P. AF305 0106A DANIELLE OB 06

MAX OUTBOUND FL WIND 119 KT NE QUAD 15:52:50Z

Sfc center not visible

Edited August 27, 2010 by Iceberg

[Iceberg]

Just past through the NW eye wall.

173130 2710N 06014W 6959 02823 //// +095 //// 055100 105 087 028 05

173200 2709N 06013W 6939 02808 //// +101 //// 059098 106 085 054 05

173400 2704N 06008W 6965 02675 9436 +169 +136 061032 033 031 004 03

Pressure of 943mb

With pretty unspectacular winds.

[Iceberg]

Well they've had a goos luck inside the eye and found a few sub 940 readings but no stronger winds, so all quads have been tested and I'd say max winds are 105kts, CAT 3.

However Dvorak is T6 which is 115kts and the pressure would normally support 120-125kts.

So with 24hrs of possible strenghtening left we probably have a storm where the winds have yet to respond the the pressure and structure.

173430 2702N 06007W 6970 02657 9418 +178 +131 060023 026 024 004 03

173500 2701N 06006W 6962 02665 9414 +176 +132 057015 018 019 003 03

173530 2659N 06005W 6976 02643 9399 +191 +129 045002 007 016 004 00

173600 2658N 06004W 6962 02660 9396 +195 +128 245012 015 015 004 00

173630 2656N 06002W 6970 02661 9411 +192 +124 236029 036 029 005 03

173700 2655N 06002W 6956 02693 9434 +177 +135 243042 047 /// /// 03

173730 2655N 06004W 6967 02667 9432 +169 +131 248038 046 030 005 03

173800 2656N 06005W 6959 02665 9412 +181 +110 243012 018 028 004 00

173830 2657N 06007W 6974 02647 9411 +184 +095 347004 008 017 004 00

173900 2659N 06008W 6965 02662 9419 +179 +097 027014 018 017 004 00

173930 2700N 06009W 6974 02656 9430 +171 +100 037020 020 015 005 03

174000 2702N 06009W 6970 02668 9440 +166 +106 041024 026 /// /// 03

174030 2703N 06008W 6966 02672 9428 +180 +100 060023 027 /// /// 03

174100 2702N 06006W 6934 02695 9413 +181 +094 049014 016 005 005 03

174130 2700N 06005W 6962 02661 9406 +188 +092 081004 008 004 006 00

174200 2659N 06004W 6964 02663 9405 +192 +089 208011 015 013 005 00

174230 2657N 06003W 6971 02652 9409 +188 +102 216023 031 030 006 00

174300 2656N 06001W 6970 02669 9430 +177 +119 229054 062 052 006 00

174330 2655N 06000W 6974 02694 9478 +161 +137 225079 086 063 007 00

174400 2654N 05959W 6974 02734 9532 +149 +136 228100 109 067 008 00