WTNT43 KNHC 062048
TCDAT3
TROPICAL STORM MARCO DISCUSSION NUMBER   2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
500 PM EDT MON OCT 06 2008
 
A TIMELY MISSION FROM THE AIR FORCE RESERVE HURRICANE HUNTERS...
TASKED WITH LITTLE ADVANCE NOTICE...REVEALS THAT THE DEPRESSION
OVER THE EXTREME SOUTHWESTERN GULF OF MEXICO HAS INTENSIFIED INTO A
TROPICAL STORM.  PEAK SFMR WINDS WERE 53 KT AND PEAK FLIGHT-LEVEL
WINDS WERE 61 KT.  THESE DATA SUPPORT AN INITIAL INTENSITY OF
ABOUT 55 KT.  SINCE THE OCEANIC AND ATMOSPHERIC ENVIRONMENT ARE
SEEMINGLY FAVORABLE...ADDITIONAL INTENSIFICATION IS SHOWN IN LINE
WITH THE LATEST SHIPS GUIDANCE.  MARCO COULD BE NEAR HURRICANE
STRENGTH AS IT APPROACHES THE COAST...AND ACCORDINGLY A HURRICANE
WATCH HAS BEEN ISSUED FOR A PORTION OF THE GULF COAST OF MEXICO.
IT SHOULD BE NOTED THAT IF THE CURRENT INTENSIFICATION TREND
CONTINUES...IT MAY BE NECESSARY TO ISSUE A HURRICANE WARNING LATER
THIS EVENING.
 
INITIAL MOTION...295/9...IS A LITTLE TO THE RIGHT OF THE PREVIOUS
ESTIMATE.  DYNAMICAL GUIDANCE DOES NOT INDICATE MUCH CHANGE IN
HEADING OVER THE NEXT 1-2 DAYS DUE TO A PRONOUNCED MID-LEVEL RIDGE
TO THE NORTH OF MARCO.  THE OFFICIAL FORECAST TRACK IS SHIFTED ONLY
SLIGHTLY TO RIGHT OF THE PREVIOUS ONE AND IS ROUGHLY IN THE MIDDLE
OF THE TRACK GUIDANCE SUITE.
 
WE THANK THE 53RD WEATHER RECONNAISSANCE SQUADRON FOR THEIR QUICK
RESPONSE TO OUR SHORT-NOTICE REQUEST TO INVESTIGATE THIS STORM.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      06/2100Z 19.5N  94.7W    55 KT
 12HR VT     07/0600Z 20.0N  95.6W    60 KT
 24HR VT     07/1800Z 20.5N  97.0W    60 KT
 36HR VT     08/0600Z 21.0N  98.5W    25 KT...INLAND
 48HR VT     08/1800Z...DISSIPATED
 
$$
FORECASTER RHOME/PASCH
 

WTNT43 KNHC 070232
TCDAT3
TROPICAL STORM MARCO DISCUSSION NUMBER   3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
1100 PM EDT MON OCT 06 2008
 
MINIATURE MARCO HAS MAINTAINED ONE SMALL COLD-TOPPED THUNDERSTORM
CLUSTER...ABOUT THE SIZE OF THE STATE OF DELAWARE...OVER THE
LOW-LEVEL CENTER. THEREFORE...THE INITIAL INTENSITY IS BEING KEPT
AT 55 KT IN LINE WITH THE LAST AIR FORCE RECON DATA...EVEN THOUGH
DVORAK SATELLITE CLASSIFICATIONS ARE T2.0/30 KT FROM BOTH TAFB AND
SAB. I HAVE WORKED SOME TINY TYPHOONS IN THE WESTERN PACIFIC
BEFORE...BUT HORIZONTALLY-CHALLENGED MARCO COULD BE THE SMALLEST
TROPICAL CYCLONE ON RECORD.
 
INITIAL MOTION ESTIMATE 295/06. MARCO HAS REMAINED ON THE PREVIOUS
FORECAST TRACK...SO THERE IS NO CHANGE SIGNIFICANT CHANGE TO THE
PREVIOUS FORECAST TRACK OR REASONING. MARCO IS EXPECTED TO MAINTAIN
A GENERAL WEST-NORTHWESTWARD MOTION TO THE SOUTH OF A STRONG
MID-LEVEL RIDGE PARKED OVER MOST OF THE GULF OF MEXICO...AND MAKE
LANDFALL IN 18 HOURS OR SO. THE OFFICIAL FORECAST TRACK IS ROUGHLY
IN THE MIDDLE OF THE NHC MODEL GUIDANCE SUITE.
 
ALTHOUGH MARCO MAY BE SMALL IN STATURE...IT HAS BEEN ABLE TO
MAINTAIN DEEP CONVECTION NEAR THE SMALL CIRCULATION CENTER THAT
ONLY HAS A RADIUS OF MAXIMUM WINDS OF ABOUT 4 NMI. SMALL SYSTEMS
LIKE MARCO CAN SPIN UP QUICKLY...BUT THEY CAN ALSO SPIN DOWN JUST
AS FAST. VERTICAL SHEAR IS FORECAST TO REMAIN RELATIVELY LOW AND
SSTS ARE EXPECTED TO BE ABOVE 28C UNTIL LANDFALL IN ABOUT 18 HOURS.
THEREFORE...SOME SLIGHT STRENGTHENING IS POSSIBLE. THE SHIPS MODEL
BRINGS MARCO UP TO HURRICANE INTENSITY IN 12 HOURS...AND UP TO 71
KT IN 18 HOURS...WHICH SEEMS A LITTLE TO AGGRESSIVE AT THIS STAGE.
THE OFFICIAL INTENSITY FORECAST IS A BLEND OF THE STRONGER HWRF AND
THE WEAKER GFDL...WHICH KEEPS MARCO JUST BELOW HURRICANE STRENGTH.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      07/0300Z 19.8N  95.4W    55 KT
 12HR VT     07/1200Z 20.2N  96.4W    60 KT
 24HR VT     08/0000Z 20.7N  97.8W    25 KT...DISSIPATING INLAND
 36HR VT     08/1200Z...DISSIPATED INLAND OVER EASTERN MEXICO
 
$$
FORECASTER STEWART
 

WTNT43 KNHC 070852
TCDAT3
TROPICAL STORM MARCO DISCUSSION NUMBER   4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
500 AM EDT TUE OCT 07 2008
 
WITH NO ADDITIONAL RECONNAISSANCE DATA SINCE YESTERDAY AFTERNOON...
THE INTENSITY OF MARCO IS VERY DIFFICULT TO ESTIMATE.  THE OVERALL
SATELLITE PRESENTATION LOOKS ABOUT THE SAME AS WHEN THE AIRCRAFT
WAS THERE LAST...SO I'LL LEAVE THE ADVISORY INTENSITY AT 55 KT. 
THE CYCLONE HAS PROBABLY ANOTHER 6-9 HOURS OVER WATER...SO SOME
FURTHER STRENGTHENING IS POSSIBLE...AND THE OFFICIAL FORECAST IS
SIMILAR TO THE PREVIOUS ADVISORY AND THE SHIPS GUIDANCE IN CALLING
FOR MARCO TO BE NEAR HURRICANE STRENGTH AT LANDFALL.  AS WE HAVE
NOTED PREVIOUSLY...HOWEVER...SMALL CYCLONES ARE PARTICULARLY
SUBJECT TO LARGE AND MOSTLY UNPREDICTABLE CHANGES IN INTENSITY. 
EXAMINATION OF THE HIGH-RESOLUTION QUIKSCAT DATA FROM 0100 UTC
SUGGESTS THAT THE RADIAL EXTENT OF TROPICAL STORM FORCE WINDS IS
EXCEEDINGLY SMALL...PERHAPS NO MORE THAN ABOUT 10 NMI. 

THE INITIAL MOTION ESTIMATE IS 295/7.  A NARROW MID-LEVEL RIDGE OF
HIGH PRESSURE SEPARATES MARCO FROM A MID- TO UPPER-LEVEL TROUGH
MOVING INTO THE NORTHERN GULF OF MEXICO.  GIVEN THE SIZE OF THE
TROPICAL CYCLONE...THIS RIDGE SHOULD BE SUFFICIENT TO KEEP MARCO ON
BASICALLY THE SAME TRACK UNTIL LANDFALL...ALTHOUGH I WOULDN'T BE
SURPRISED IF THE TRACK BENDS SLIGHTLY TO THE RIGHT...WHICH WOULD
KEEP MARCO OVER WATER LONGER THAN CURRENTLY FORECAST.  THE OFFICIAL
FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY AND IN BEST AGREEMENT
WITH THE UKMET AND BAM GUIDANCE.  

 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      07/0900Z 20.1N  96.1W    55 KT
 12HR VT     07/1800Z 20.5N  97.1W    60 KT...JUST INLAND
 24HR VT     08/0600Z 20.9N  98.5W    20 KT...REMNANT LOW
 36HR VT     08/1800Z...DISSIPATED
 
$$
FORECASTER FRANKLIN
 

WTNT43 KNHC 071446
TCDAT3
TROPICAL STORM MARCO DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
1100 AM EDT TUE OCT 07 2008
 
HIGH-RESOLUTION VISIBLE SATELLITE IMAGERY INDICATES THAT MARCO HAS 
MADE LANDFALL AND THE CENTER IS JUST INLAND OF THE COAST OF CENTRAL
MEXICO.  THE MOTION HAS BEEN AROUND 270/6 OVER THE PAST FEW
HOURS...AND A GENERAL WESTWARD TO WEST-NORTHWESTWARD HEADING IS
EXPECTED TO CONTINUE TODAY AND TONIGHT.  SINCE THE MOUNTAINS OVER
CENTRAL MEXICO ARE QUITE HIGH...RAPID WEAKENING IS EXPECTED.  A 24
HOUR FORECAST POSITION IS SHOWN BUT IT IS DOUBTFUL THAT A
WELL-DEFINED SURFACE CIRCULATION WILL LAST THAT LONG.  IN
FACT...MARCO COULD DISSIPATE TONIGHT OR VERY EARLY WEDNESDAY. 
STILL...THE REMNANTS OF MARCO COULD PRODUCE VERY HEAVY RAINS OVER
EASTERN PORTIONS OF CENTRAL MEXICO DURING THE NEXT DAY OR SO.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      07/1500Z 19.9N  96.6W    55 KT...INLAND
 12HR VT     08/0000Z 20.3N  97.9W    35 KT...INLAND
 24HR VT     08/1200Z 20.3N  98.8W    20 KT...REMNANT LOW
 36HR VT     09/0000Z...DISSIPATED
 
$$
FORECASTER RHOME/PASCH
 

WTNT43 KNHC 072033
TCDAT3
TROPICAL DEPRESSION MARCO DISCUSSION NUMBER   6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
500 PM EDT TUE OCT 07 2008
 
MARCO'S SATELLITE PRESENTATION HAS DEGRADED RAPIDLY SINCE THE CENTER
MOVED INLAND OVER MEXICO THIS MORNING.  THE INITIAL INTENSITY
IS LOWERED TO 30 KT AND MARCO IS NOW A TROPICAL DEPRESSION. 
CONTINUED WEAKENING IS EXPECTED AS THE CENTER TRACKS GENERALLY
WESTWARD OVER THE VERY HIGH TERRAIN OF CENTRAL MEXICO...AND MARCO
IS EXPECTED TO DISSIPATE TONIGHT OR EARLY WEDNESDAY.  STILL...THE
REMNANTS OF MARCO ARE EXPECTED TO PRODUCE HEAVY RAINS AND THE
POTENTIAL FOR FLASH FLOODING OVER EASTERN PORTIONS OF CENTRAL
MEXICO DURING THE NEXT DAY OR TWO. 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      07/2100Z 19.9N  97.1W    30 KT
 12HR VT     08/0600Z 19.9N  97.9W    25 KT...INLAND
 24HR VT     08/1800Z...DISSIPATED
 
$$
FORECASTER RHOME/PASCH
 

WTNT43 KNHC 080238
TCDAT3
TROPICAL DEPRESSION MARCO DISCUSSION NUMBER   7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL132008
1100 PM EDT TUE OCT 07 2008

SATELITE AND SURFACE OBSERVATIONS SUGGEST THAT THE TINY CIRCULATION
OF MARCO HAS DISINTEGRATED OVER MEXICO. THUS...THIS WILL BE THE
LAST ADVISORY. THE ONLY REMAINING THREAT WITH THIS SYSTEM IS
LOCALLY HEAVY RAINS AND THE POTENTIAL FOR FLASH FLOODING OVER
EASTERN PORTIONS OF CENTRAL MEXICO DURING THE NEXT DAY OR SO.
  
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      08/0300Z 20.0N  97.5W    20 KT
 12HR VT     08/1200Z...DISSIPATED
 
$$
FORECASTER BLAKE
 

