EPAC: Invest 93E - ex. Dean

[HURAKAN]

Time will tell if we see some development.

[HURAKAN]

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1000 AM PDT THU AUG 23 2007

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE.

A BROAD AREA OF DISTURBED WEATHER...ASSOCIATED WITH THE REMNANTS OF
ATLANTIC HURRICANE DEAN...IS LOCATED NEAR THE COAST OF MEXICO IN
THE VICINITY OF MANZANILLO. DEVELOPMENT...IF ANY IS EXPECTED TO BE
SLOW AS THE SYSTEM MOVES WESTWARD OR WEST-NORTHWESTWARD OVER THE
NEXT COUPLE OF DAYS.

IT SHOULD BE NOTED THAT IF THIS SYSTEM WERE TO REGENERATE INTO A
NAMED TROPICAL CYCLONE...IT WOULD NOT RETAIN THE NAME DEAN SINCE
DEAN DID NOT MAINTAIN ITS STATUS AS A TROPICAL CYCLONE OVER THE
MOUNTAINS OF MEXICO.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$

FORECASTER PASCH

[Lowpressure]

I know it is policy, but if you know it is the remants of, then why would it not be Dean? I can read and understand the explanation, it just seems foolish. If it looks like a dog and smells like a dog then.....

[tolakram]

I feel the same way. If it develops it's Dean to me. If it wasn't for Dean nothing would be there.

[HURAKAN]

It's kind of ambiguous and difficult to comprehend, but when a cyclone's LLC dissipates and a new one develops, then it's called by another name.

The ambiguity comes here, when we have a tropical storm organizing and one LLC dissipates because the system relocated to another LLC, didn't it lost the original LLC and isn't it now a new system based on the rule governing crossing systems?

I guess it has to do with the interaction with land then.

[HURAKAN]

Here is a contradiction of the rule: TS Bonnie.

TD 2 dissipates:
TROPICAL DEPRESSION TWO DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT WED AUG 04 2004

WE GAVE THE DEPRESSION THE BENEFIT OF THE DOUBT THIS MORNING WHEN
THE RECONNAISSANCE AIRCRAFT COULDN'T CLOSE OFF A CENTER. THIS
AFTERNOON THE CONVECTION HAS BECOME ELONGATED EAST-WEST AND LESS
CONCENTRATED...AND THERE IS NO REASON TO BELIEVE THE SYSTEM HAS
RE-DEVELOPED A SURFACE CIRCULATION. GIVEN THE LACK OF A CENTER
THIS MORNING AND THE OBSERVED CONVECTIVE TRENDS SINCE THEN...
ADVISORIES ARE BEING DISCONTINUED AT THIS TIME.

MODEL GUIDANCE HAS CHANGED SINCE THIS MORNING. THE GFDL...WHICH
EARLIER STRENGTHENED THE DEPRESSION AND TOOK IT NORTHWEST AND THEN
NORTH...NOW TAKES THE SYSTEM WEST AND DISSIPATES IT. THE GFS ALSO
NOW AGREES WITH THIS SCENARIO. THE MAJOR THREAT FROM THIS SYSTEM
WOULD BE IF IT MOVED FAR ENOUGH NORTH TO BRING RAINFALL TO
HISPANIOLA.

AN AIR FORCE RESERVE UNIT RECONNAISSANCE AIRCRAFT WILL INVESTIGATE
THE REMNANTS OF THE DEPRESSION TOMORROW MORNING...IF NECESSARY.

FORECASTER FRANKLIN

FORECAST POSITIONS AND MAX WINDS

INITIAL 04/2100Z 13.5N 63.5W 30 KT...DISSIPATING
12HR VT 05/0600Z...DISSIPATED


TD 2 regenerates as Bonnie:
TROPICAL STORM BONNIE DISCUSSION NUMBER 7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT MON AUG 09 2004

AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT INVESTIGATING THE
REMNANTS OF FORMER TROPICAL DEPRESSION TWO FOUND A SMALL BUT VERY
TIGHT SURFACE CIRCULATION AND 56 KT 1500 FT FLIGHT-LEVEL WINDS.
NORMALLY THIS WOULD EQUATE TO 48 SURFACE WINDS...BUT THE CONVECTION
OVER THE CENTER IS SMALL AND NOT PARTICULARLY WELL ORGANIZED. THE
RAPID SPIN UP IN THE LOW-LEVEL WIND FIELD COULD EASILY SPINDOWN IF
THE INNER-CORE CONVECTION WEAKENS OR DISSIPATES. SO THE INITIAL
INTENSITY IS A BLEND OF THE RECON WINDS AND A DVORAK SATELLITE
INTENSITY ESTIMATE OF T2.5...OR 35 KT...FROM TAFB.

THE INITIAL MOTION ESTIMATE IS 310/10. THERE IS LIMITED MODEL
GUIDANCE AVAILABLE FOR THIS FORECAST PACKAGE SINCE NONE OF THE
GLOBAL MODELS INITIALIZED THE BONNIE CIRCULATION VERY WELL AT 12Z.
HOWEVER...ALL OF THE GLOBAL AND REGIONAL MODELS AGREE ON TAKING A
WEAK MID-LEVEL TROUGH FROM OVER THE SOUTHERN PLAINS SOUTHEASTWARD
TO THE NORTH-CENTRAL GULF OF MEXICO AND WEAKENING THE SUBTROPICAL
RIDGE TO THE NORTH OF BONNIE. THE RESULT SHOULD BE A GRADUAL TURN
TOWARD THE NORTH WITH A DECREASE IN FORWARD SPEED AS THE STEERING
CURRENTS WEAKEN. BY 48 HOURS...BONNIE IS EXPECTED TO TURN
NORTHEASTWARD AND GRADUALLY ACCELERATE AHEAD OF A SECOND AND
STRONGER MID-LEVEL TROUGH THAT IS FORECAST TO PUSH SOUTHEASTWARD
INTO THE WESTERN GULF OF MEXICO IN 48 TO 72 HOURS. THE OFFICIAL
FORECAST TRACK IS A BLEND OF THE GFDL...DEEP AND MEDIUM BAM...AND
THE GFS 10-MEMBER ENSEMBLE MODEL FORECASTS.

THE INTENSITY FORECAST IS SOMEWHAT PROBLEMATIC. BONNIE HAS A SMALL
AND TIGHT CIRCULATION...AND WILL BE MOVING INTO A LOWER VERTICAL
SHEAR REGION OVER THE CENTRAL GULF OF MEXICO...WHICH WOULD NORMALLY
FAVOR SIGNIFICANT INTENSIFICATION TO OCCUR. THE SHIPS MODEL BRINGS
BONNIE TO 83 KT IN 72 HOURS...WHILE THE GFDL TAKES THE CYCLONE UP
TO 74 KT AT THE SAME TIME PERIOD. THE ARGUMENT AGAINST FORECASTING
ANY ROBUST INTENSIFICATION FROM OCCURRING...AT LEAST IN THE SHORT
TERM...IS THE ABUNDANCE OF VERY DRY AIR SURROUNDING THE CYCLONE...
AS SEEN IN WATER VAPOR IMAGERY...THAT BONNIE WILL HAVE TO NAVIGATE
THROUGH FOR THE NEXT 24 TO 48 HOURS.

FORECASTER STEWART

FORECAST POSITIONS AND MAX WINDS

INITIAL 09/2100Z 23.2N 88.7W 40 KT
12HR VT 10/0600Z 24.3N 90.0W 45 KT
24HR VT 10/1800Z 25.3N 90.3W 45 KT
36HR VT 11/0600Z 26.5N 90.2W 50 KT
48HR VT 11/1800Z 27.4N 89.5W 50 KT
72HR VT 12/1800Z 30.0N 86.5W 50 KT
96HR VT 13/1800Z 34.0N 80.5W 25 KT...INLAND
120HR VT 14/1800Z...DISSIPATED
_____________________

TD 1: Alex
TD 2: LLC dissipates
TD 2: New LLC, develops as Bonnie
TD 3: Charley
TD 4: Danielle
TD 5: Earl
and so on.

[Lowpressure]

Did this happen with TD-10/TD12/ Katrina, or am I confusing the issue?

[Brent]

Kind of... I'm confused.

THE NWS RULES GOVERNING THE NAMING OF TROPICAL CYCLONES SPECIFY
THAT...WITHIN A BASIN...WHEN A CYCLONE FORMS FROM THE REMNANT OF A
PREVIOUSLY EXISTING CYCLONE...THE OLD NAME/NUMBER IS RETAINED.
TROPICAL DEPRESSION TWELVE HAS A COMPLEX GENESIS THAT LIKELY
INCLUDES A MID-LEVEL REMNANT OF FORMER TROPICAL DEPRESSION TEN. A
REVIEW OF SATELLITE AND RAWINSONDE DATA OVER THE PAST WEEK OR SO
SUGGESTS THAT A SECOND DISTURBANCE APPROACHED AND COMBINED WITH THE
MID-LEVEL REMNANT OF TROPICAL DEPRESSION TEN ON 20 AUGUST. BECAUSE
IT IS IMPOSSIBLE TO DETERMINE WHICH OF THESE TWO SYSTEMS IS
ASSOCIATED WITH TODAY'S GENESIS...WE HAVE ELECTED TO USE THE
DESIGNATION TWELVE RATHER THAN TEN FOR THE NEW DEPRESSION. THIS
SITUATION DIFFERS FROM LAST YEAR'S REGENERATION OF IVAN...IN WHICH
THE LOW-LEVEL REMNANT OF THAT SYSTEM REMAINED A DISTINCT FEATURE
THAT COULD BE FOLLOWED CONTINUOUSLY UNTIL IT REGENERATED.

I still don't believe Ivan II was really Ivan either.

[fasterdisaster]

The reason is because it is in a different basin, and was unable to remain a tropical depression. Bonnie was not a contradiction, if a Bonnie had developed between Alex and regenerated-TD 2, then the system would be titled Charley. However if TD2 didn't regenerate into a TS right away and only into a TD, it would still be TD2, not TD3 or TD4.

Katrina was the same issue, but the outcome was different and rightly so. A low pressure system merged with the remnants of TD 10, and it couldn't be determined if TD 10 or the low pressure system was the main cause of the new system. Thusly, it was titled TD12. If TD 10 turned into a TS before dissipating, then it would be titled Tropical Storm Jose. Instead, a Jose had already formed before TD10's remnants merged with a low pressure system became TD 12, and TD 12 became Katrina.

Another system that crossed basins while clearly being the remnants of another system was Hurricane Fifi, which became a system in the Pacific after crossing Nicaragua, though I can't remember what Fifi was renamed in the Pacific, it did correspond to the Pacific's naming list.

Hope this clears it up a little.

[Lowpressure]

Thanks for the clarification- good work.

[cycloneye]

000
ABPZ20 KNHC 232233
TWOEP
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
400 PM PDT THU AUG 23 2007

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE.

A BROAD AREA OF SHOWERS...ASSOCIATED WITH THE REMNANTS OF
ATLANTIC HURRICANE DEAN...IS LOCATED ALONG THE COAST OF MEXICO FROM
MANZANILLO TO MAZATLAN. DEVELOPMENT...IF ANY...IS EXPECTED TO BE
SLOW TO OCCUR AS THE SYSTEM MOVES WEST-NORTHWESTWARD OVER THE NEXT
COUPLE OF DAYS.

IT SHOULD BE NOTED THAT IF THIS SYSTEM WERE TO REGENERATE INTO A
NAMED TROPICAL CYCLONE...IT WOULD NOT RETAIN THE NAME DEAN SINCE
DEAN DID NOT MAINTAIN ITS STATUS AS A TROPICAL CYCLONE OVER THE
MOUNTAINS OF MEXICO.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$

FORECASTER LANDSEA/AVILA

[Dick Pache]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU AUG 23 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2100 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 81W N OF 4N THROUGH WRN PANAMA MOVING W
10 TO 15 KT. NO SIGNIFICANT CONVECTION IS ASSOCIATED WITH THIS
WAVE EXCEPT FOR SCATTERED MODERATE THUNDERSTORMS OVER THE
MOUNTAINS OF WESTERN PANAMA.

TROPICAL WAVE IS ALONG 120 N OF 4N MOVING W 10 TO 15 KT. TO 16N
MOVING W 10-15 KT. NO SIGNIFICANT CONVECTION ASSOCIATED WITH
THIS WAVE.

...ITCZ...
ITCZ AXIS IS ALONG 5N77W 6N92W 12N119W 8N130W 9N140W. SCATTERED
MODERATE FROM 10N TO 13N BETWEEN 93W AND 105W.

...DISCUSSION...
E OF 120W...A CLUSTER OF STRONG CONVECTION IS FLARING OFF THE
MEXICAN COAST NEAR MAZATLAN...ASSOCIATED WITH THE REMNANTS OF
HURRICANE DEAN. LOW PRES 1005 MB IS ANALYZED ALONG THE COAST S
OF PUERTO VALLARTA. THIS SYSTEM IS EXPECTED REMAIN FAIRLY WEAK
AS IT MOVES NNW INTO THE SRN GULF OF CALIFORNIA E OF LOS CABOS.
SHIP REPORTS TO THE SW OF THE LOW INDICATE WINDS ARE UP TO 20
KT. THE STORM WILL MAINTAIN FRESH WINDS IN THE VICINITY...BEFORE
WEAKENING AFTER 24 HOURS AS IT MOVES FURTHER N. ELSEWHERE...ONLY
MODEST CONVECTION IS EVIDENT. NELY FLOW ALOFT ON THE W SIDE OF
AN UPPER LOW E OF THE YUCATAN IS SUPPRESSING CONVECTIVE
DEVELOPMENT ALONG THE ITCZ OFF THE SRN MEXICAN AND GUATEMALAN
COASTS. CONVECTION MAY FLARE OVER THE NEXT COUPLE OF DAYS
HOWEVER AS THE TROPICAL WAVE NEAR 89W MIGRATES INTO THE
AREA...AND AN UPPER TROUGH OVER THE YUCATAN SHIFTS W TO 95W
THROUGH FRI. FURTHER S...A SURGE OF SLY FLOW S OF THE EQUATOR
WILL DELIVER MODERATE TO LARGE SWELL INTO THE AREA S OF 10N OVER
THE NEXT COUPLE OF DAYS.

W OF 120W...DRY SUBSIDENT AIR PREVAILS OVER THE AREA LIMITING
ANY SIGNIFICANT CONVECTION...EVEN ALONG THE WEAK TROPICAL WAVE
NEAR 120W. SHIP OBSERVATIONS ARE SHOWING FRESH NLY FLOW IN THE
AREA N OF 28N...ON THE PERIPHERY OF SURFACE HIGH PRES 1032 MB
CENTERED NW OF THE AREA. SATELLITE IMAGERY SHOWS FIELD OF
STRATOCUMULUS OVER THIS AREA AS WELL.

$$
CHRISTENSEN

[cycloneye]

000
ABPZ20 KNHC 241009
TWOEP
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
400 AM PDT FRI AUG 24 2007

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE.

SHOWERS ASSOCIATED WITH THE REMNANTS OF ATLANTIC HURRICANE DEAN ARE
LOCATED NEAR BAJA CALIFORNIA. THIS ACTIVITY REMAINS DISORGANIZED AND
FURTHER DEVELOPMENT OF THE SYSTEM IS NOT ANTICIPATED.

TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS.

$$

FORECASTER LANDSEA/AVILA


Its over.

[NetZeroZeus]

Hallelujah!
Now Mexico can get back on track hopefully.

[Chacor]

Gone from NRL.

[mitchell]

I know it is policy, but if you know it is the remants of, then why would it not be Dean? I can read and understand the explanation, it just seems foolish. If it looks like a dog and smells like a dog then.....

Probably easier to draw a bright line somewhere and the easist bright line to draw is TD. Anything below TD (i.e. remnants) would be pretty subjective.

[Ptarmigan]

Where did Dean's remnant go?

[Chacor]

Up the Gulf of California.

[JonathanBelles]

http://www.ssd.noaa.gov/goes/west/weus/loop-vis.html

Dean ^^^?