CAT 5 Hurricane Dean - Archived threads

[mempho]

there is nothing that supports cat 5 yet. The FL winds are at FL, the SFMR and dropsondes are still below cat 5; thus, it is not a cat 5

We have exactly 156mph surface, don't we?

[cycloneye]

[RL3AO]

there is nothing that supports cat 5 yet. The FL winds are at FL, the SFMR and dropsondes are still below cat 5; thus, it is not a cat 5

We have exactly 156mph surface, don't we?

The .9 formula is a guesstimate. SMFR (?) doesn't show winds close to that.

[Derek Ortt]

no we dont have 156 surface... not yet at least

[Downdraft]

4 or 5 who really cares? It's a helluva tropical cyclone.

[Sanibel]

The small islands of Islas Santanillas off Honduras are in the south core right now. I would guess around 100mph or more.

I think Ambergris Caye Belize is going to take the south core and good hurricane winds later this evening. I mean like, maybe, 100mph.

My opinions are not endorsed by Storm2k

[sevenleft]

there is nothing that supports cat 5 yet. The FL winds are at FL, the SFMR and dropsondes are still below cat 5; thus, it is not a cat 5

We have exactly 156mph surface, don't we?

The .9 formula is a guesstimate. SMFR (?) doesn't show winds close to that.

Well, you don't know that, since SFMR winds haven't been received since the SE eyewall hours ago.

[WxGuy1]

there is nothing that supports cat 5 yet. The FL winds are at FL, the SFMR and dropsondes are still below cat 5; thus, it is not a cat 5

We have exactly 156mph surface, don't we?

No, we are close to an ESTIMATE of 156mph based on flight-level data. Other data obtained so far do NOT support such an intensity. It is really, really important to remember than the 0.9 reduction factor is nothing but a rough estimate (and it's more likely to be an overestimate than an underestimate). A 0.85 reduction factor yields something like 147 mph, which seems to match up pretty well with other observations. The vertical profile of horizontal wind near the eyewall is very complex, and has been shown to vary remarkably from storm-to-storm, and even from time-to-time within the same storm. For all we know, a reduction factor closer to 0.8 may be best for Dean at this time. Personally, I'm using 0.85 with Dean right now based on what I've seen from other observations.

[Matt-hurricanewatcher]

It looks ten times better then it did last night. The visible when you loop it shows a very very good eye. It is likely slowly strengthing right now...We will see if it can become cat5.

[RL3AO]

The .9 formula is a guesstimate. SMFR (?) doesn't show winds close to that.

Well, you don't know that, since SFMR winds haven't been received since the SE eyewall hours ago.[/quote]

Just another nail in the Cat 4 coffin.

[Derek Ortt]

from what I have seen so far, it is not that bad in eastern Jamaica, less damage than Gilbert

[Tom8]

Could somone send some links to the current pictures of the hurrican Dean please .

[CrazyC83]

First damage estimate found: Insured between $1.5 billion and $3 billion (US). That would translate to between $3 billion and $6 billion total with a 2-1 ratio of insured to non-insured property.

http://www.insurancejournal.com/news/in ... /82848.htm

[Derek Ortt]

the SFMR winds have been reported in the VDMs. That line is no longer a surface wind visual estimate, it is the SFMR wind.

There is merely a problem with the HDOBS getting onto the website and we are only getting the very low resolution obs

[Brent]

HURRICANE DEAN FORECAST/ADVISORY NUMBER 31
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
2100 UTC MON AUG 20 2007

AT 5 PM EDT...2100 UTC...THE GOVERNMENT OF MEXICO HAS ISSUED A
TROPICAL STORM WATCH FROM WEST OF CIUDAD DEL CARMEN TO VERACRUZ.

AT 5 PM EDT...ALL WARNINGS IN THE CAYMAN ISLANDS ARE DISCONTINUED.

A TROPICAL STORM WATCH REMAINS IN EFFECT FOR THE FOLLOWING PROVINCES
OF CUBA...PINAR DEL RIO...LA HABANA...AND ISLA DE LA JUVENTUD. AT 5
PM EDT...ALL OTHER WATCHES AND WARNINGS IN CUBA ARE DISCONTINUED.

A HURRICANE WARNING REMAINS IN EFFECT FOR THE ENTIRE COASTLINE OF
BELIZE...ALONG THE EAST COAST OF THE YUCATAN PENINSULA FROM THE
BELIZE/MEXICO BORDER NORTHWARD TO CANCUN...AND ALONG THE WEST COAST
OF THE YUCATAN PENINSULA FROM SOUTH OF PROGRESSO SOUTHWARD TO
CIUDAD DEL CARMEN. PREPARATIONS TO PROTECT LIFE AND PROPERTY
SHOULD BE RUSHED TO COMPLETION.

A TROPICAL STORM WARNING REMAINS IN EFFECT ON THE YUCATAN PENINSULA
FROM NORTH OF CANCUN TO PROGRESSO.

INTERESTS ELSEWHERE IN THE SOUTHERN GULF OF MEXICO SHOULD CLOSELY
MONITOR THE PROGRESS OF DEAN.

HURRICANE CENTER LOCATED NEAR 18.2N 84.2W AT 20/2100Z
POSITION ACCURATE WITHIN 10 NM

PRESENT MOVEMENT TOWARD THE WEST OR 275 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 918 MB
EYE DIAMETER 20 NM
MAX SUSTAINED WINDS 130 KT WITH GUSTS TO 160 KT.
64 KT....... 50NE 40SE 30SW 50NW.
50 KT....... 90NE 75SE 50SW 75NW.
34 KT.......150NE 150SE 85SW 120NW.
12 FT SEAS..300NE 300SE 250SW 300NW.
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 18.2N 84.2W AT 20/2100Z
AT 20/1800Z CENTER WAS LOCATED NEAR 18.0N 83.2W

FORECAST VALID 21/0600Z 18.5N 86.7W
MAX WIND 140 KT...GUSTS 170 KT.
64 KT... 50NE 40SE 30SW 50NW.
50 KT... 90NE 75SE 50SW 75NW.
34 KT...150NE 150SE 85SW 120NW.

FORECAST VALID 21/1800Z 19.3N 90.2W...INLAND
MAX WIND 75 KT...GUSTS 90 KT.
64 KT... 25NE 15SE 15SW 25NW.
50 KT... 60NE 60SE 30SW 75NW.
34 KT...150NE 90SE 50SW 150NW.

FORECAST VALID 22/0600Z 20.2N 93.6W
MAX WIND 85 KT...GUSTS 105 KT.
64 KT... 40NE 30SE 20SW 40NW.
50 KT... 75NE 60SE 40SW 60NW.
34 KT...150NE 120SE 75SW 150NW.

FORECAST VALID 22/1800Z 21.0N 97.0W
MAX WIND 95 KT...GUSTS 115 KT.
50 KT... 75NE 60SE 40SW 75NW.
34 KT...150NE 120SE 50SW 150NW.

FORECAST VALID 23/1800Z 21.5N 103.0W...INLAND
MAX WIND 30 KT...GUSTS 50 KT.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 325 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 24/1800Z...DISSIPATED

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.2N 84.2W

NEXT ADVISORY AT 21/0300Z

$$
FORECASTER FRANKLIN

[Sanibel]

You are looking at it the wrong way. You have to think of a muscular, large storm being pulled around at 918 pressure. Katrina was disasterous because it had a 902 pressure. The pressure pulled that surge. Dean should be the same.

[Brent]

BULLETIN
HURRICANE DEAN ADVISORY NUMBER 31
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
500 PM EDT MON AUG 20 2007

...EXTREMELY DANGEROUS HURRICANE DEAN EXPECTED TO STRIKE THE YUCATAN
TONIGHT...COULD REACH CATEGORY FIVE BEFORE LANDFALL...

AT 5 PM EDT...2100 UTC...THE GOVERNMENT OF MEXICO HAS ISSUED A
TROPICAL STORM WATCH FROM WEST OF CIUDAD DEL CARMEN TO VERACRUZ.

AT 5 PM EDT...ALL WARNINGS IN THE CAYMAN ISLANDS ARE DISCONTINUED.

A TROPICAL STORM WATCH REMAINS IN EFFECT FOR THE FOLLOWING PROVINCES
OF CUBA...PINAR DEL RIO...LA HABANA...AND ISLA DE LA JUVENTUD. AT 5
PM EDT...ALL OTHER WATCHES AND WARNINGS IN CUBA ARE DISCONTINUED.

A HURRICANE WARNING REMAINS IN EFFECT FOR THE ENTIRE COASTLINE OF
BELIZE...ALONG THE EAST COAST OF THE YUCATAN PENINSULA FROM THE
BELIZE/MEXICO BORDER NORTHWARD TO CANCUN...AND ALONG THE WEST COAST
OF THE YUCATAN PENINSULA FROM SOUTH OF PROGRESSO SOUTHWARD TO
CIUDAD DEL CARMEN. PREPARATIONS TO PROTECT LIFE AND PROPERTY
SHOULD BE RUSHED TO COMPLETION.

A TROPICAL STORM WARNING REMAINS IN EFFECT ON THE YUCATAN PENINSULA
FROM NORTH OF CANCUN TO PROGRESSO.

INTERESTS ELSEWHERE IN THE SOUTHERN GULF OF MEXICO SHOULD CLOSELY
MONITOR THE PROGRESS OF DEAN.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 500 PM EDT...2100Z...THE CENTER OF HURRICANE DEAN WAS LOCATED
NEAR LATITUDE 18.2 NORTH...LONGITUDE 84.2 WEST OR ABOUT 270 MILES...
435 KM...EAST OF CHETUMAL MEXICO.

DEAN IS MOVING TOWARD THE WEST NEAR 20 MPH...32 KM/HR...AND AND A
WESTWARD OR WEST-NORTHWESTWARD MOTION IS EXPECTED OVER THE NEXT 24
HOURS. ON THIS TRACK THE CENTER OF THE HURRICANE IS EXPECTED TO
MAKE LANDFALL ON THE YUCATAN PENINSULA VERY EARLY TUESDAY MORNING.
HOWEVER...CONDITIONS WILL BEGIN TO DETERIORATE ALONG THE COASTLINE
THIS EVENING.

MAXIMUM SUSTAINED WINDS ARE NEAR 150 MPH...240 KM/HR...WITH HIGHER
GUSTS. DEAN IS AN EXTREMELY DANGEROUS CATEGORY FOUR HURRICANE ON
THE SAFFIR-SIMPSON SCALE. SOME STRENGTHENING IS EXPECTED LATER
TODAY...AND DEAN IS LIKELY TO BECOME A CATEGORY FIVE HURRICANE
PRIOR TO MAKING LANDFALL.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175
MILES...280 KM.

THE MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE RESERVE UNIT
RECONNAISSANCE AIRCRAFT WAS 918 MB...27.11 INCHES.

DEAN IS EXPECTED TO PRODUCE STORM TOTAL RAINFALL OF 5 TO 10 INCHES
OVER THE YUCATAN PENINSULA...BELIZE...GUATEMALA...AND NORTHERN
HONDURAS...WITH MAXIMUM AMOUNTS OF UP TO 20 INCHES. THESE
RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.

COASTAL STORM SURGE FLOODING OF 5 TO 7 FEET ABOVE NORMAL TIDE
LEVELS...ALONG WITH LARGE AND DANGEROUS BATTERING WAVES...IS
POSSIBLE IN THE CAYMAN ISLANDS. STORM SURGE FLOODING OF 12 TO 18
FEET ABOVE NORMAL TIDE LEVELS IS POSSIBLE NEAR AND TO THE NORTH OF
WHERE DEAN MAKES LANDFALL ALONG THE EAST COAST OF THE YUCATAN
PENINSULA.

REPEATING THE 500 PM EDT POSITION...18.2 N...84.2 W. MOVEMENT
TOWARD...WEST NEAR 20 MPH. MAXIMUM SUSTAINED WINDS...150 MPH.
MINIMUM CENTRAL PRESSURE...918 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 800 PM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 1100
PM EDT.

$$
FORECASTER FRANKLIN/RHOME

[Brent]

HURRICANE DEAN DISCUSSION NUMBER 31
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
500 PM EDT MON AUG 20 2007

COMMUNICATIONS PROBLEMS ARE PREVENTING THE RECEIPT OF MOST DATA FROM
THE AIR FORCE RECONNAISSANCE AIRCRAFT THIS AFTERNOON...ALTHOUGH A
1930Z VORTEX FIX WAS RECEIVED. AT THAT TIME THE MINIMUM PRESSURE
WAS 918 MB...WITH MAXIMUM FLIGHT-LEVEL WINDS OF 151 KT. EARLIER IN
THE FLIGHT...A PEAK SFMR WIND OF 123 KT WAS OBSERVED. DVORAK
CLASSIFICATIONS FROM TAFB AND SAB WERE 127 KT AT 18Z. BASED ON
THESE DATA...THE INITIAL INTENSITY IS HELD AT 130 KT. ALL OBJECTIVE
GUIDANCE SHOWS ADDITIONAL INTENSIFICATION OVER THE DEEP WARM WATERS
OF THE WESTERN CARIBBEAN...AND DEAN COULD REACH CATEGORY FIVE
STATUS BEFORE MAKING LANDFALL. A 15Z MICROWAVE PASS SHOWS A PARTIAL
OUTER EYEWALL...BUT THIS WILL PROBABLY NOT HAVE ENOUGH TIME TO
INDUCE ANY WEAKENING BEFORE LANDFALL. DEAN IS EXPECTED TO MAINTAIN
HURRICANE STRENGTH AS IT TRAVERSES THE YUCATAN PENINSULA...AND
APPROACH MAJOR HURRICANE STRENGTH AGAIN BEFORE ITS FINAL LANDFALL.

THE INITIAL MOTION IS 275/17. DEAN IN EXPECTED TO MAINTAIN A TRACK
BETWEEN WEST AND WEST-NORTHWEST TO THE SOUTH OF THE WESTWARD-
BUILDING SUBTROPICAL RIDGE. MOST OF THE DYNAMICAL MODEL GUIDANCE
HAS TRENDED SOUTH AND THE OFFICIAL FORECAST HAS BEEN NUDGED
SOUTHWARD. ALL THE LARGE-SCALE MODELS TAKE THE MID-LEVEL VORTICITY
OF DEAN WEST-SOUTHWESTWARD ACROSS THE MOUNTAINS OF CENTRAL
MEXICO...AND THE OFFICIAL FORECAST NOW SHOWS A LEFTWARD BEND OF THE
TRACK AFTER FINAL LANDFALL. I DO NOT ACTUALLY EXPECT A WELL-
DEFINED SURFACE CIRCULATION TO EXIST AT 72 HOURS...BUT A POINT IS
PROVIDED SO THAT IT DOESN'T APPEAR THAT THE TRACK ENDS IN THE GULF
OF MEXICO.


FORECAST POSITIONS AND MAX WINDS

INITIAL 20/2100Z 18.2N 84.2W 130 KT
12HR VT 21/0600Z 18.5N 86.7W 140 KT
24HR VT 21/1800Z 19.3N 90.2W 75 KT...INLAND
36HR VT 22/0600Z 20.2N 93.6W 85 KT
48HR VT 22/1800Z 21.0N 97.0W 95 KT
72HR VT 23/1800Z 21.5N 103.0W 30 KT...INLAND
96HR VT 24/1800Z...DISSIPATED

$$
FORECASTER FRANKLIN

[Cyclone1]

You are looking at it the wrong way. You have to think of a muscular, large storm being pulled around at 918 pressure. Katrina was disasterous because it had a 902 pressure. The pressure pulled that surge. Dean should be the same.

Actually storm surge has little to do with pressure. Winds and geography are the two main factors that enhance surge.

[cycloneye]

AT 5 PM EDT...2100 UTC...THE GOVERNMENT OF MEXICO HAS ISSUED A
TROPICAL STORM WATCH FROM WEST OF CIUDAD DEL CARMEN TO VERACRUZ.


El gobierno de Mejico esta difundiendo unsa vigilancia de Tormenta Tropical desde el oeste de Ciudad del Carmen hasta Veracruz.