[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT45 KNHC 162100
TCDAT5
HURRICANE EMILY DISCUSSION NUMBER  24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT SAT JUL 16 2005

EMILY HAS CONTINUED TO STRENGTHEN THIS AFTERNOON.  AT ABOUT 17Z...AN
AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATES THAT THE
CENTRAL PRESSURE HAS FALLEN TO 937 MB...WITH 700 MB FLIGHT-LEVEL
WINDS AS HIGH AS 151 KT IN THE NORTHEASTERN QUADRANT.  THIS SUPPORTS
THE INITIAL INTENSITY OF 135 KT.  THERE IS A POSSIBILITY THAT EMILY
HAS GOTTEN STRONGER SINCE THE AIRCRAFT LEFT THE STORM.  HOWEVER...
THE SATELLITE SIGNATURE DOES NOT YET SUPPORT STRONGER WINDS...SO
ANY FURTHER INCREASE IN THE INTITAL WINDS WILL WAIT FOR THE NEXT
AIRCRAFT SCHEDULED NEAR 00Z.

THE INITIAL MOTION REMAINS 290/16.  OTHER THAN THAT...THERE IS NO
CHANGE IN THE FORECAST PHILOSOPHY.  EMILY IS SOUTH AND SOUTHWEST OF
A DEEP LAYER RIDGE EXTENDING FROM THE ATLANTIC ACROSS FLORIDA INTO
THE NORTHERN GULF OF MEXICO.  LARGE-SCALE MODELS AGREE THIS RIDGE
SHOULD BUILD SLOWLY WESTWARD...WITH PERHAPS A WEAKNESS REMAINING
OVER EASTERN TEXAS AS A SHORTWAVE TROUGH MOVES THROUGH THE NORTH
CENTRAL U.S.  EMILY SHOULD CONTINUE WEST-NORTHWESTWARD FOR 36-48
HR...WHICH SHOULD TAKE THE CENTER NEAR OR OVER THE YUCATAN
PENINSULA OF MEXICO.  AFTER THAT...THE EXACT TRACK DEPENDS ON HOW
MUCH WEAKNESS THERE IS IN THE RIDGE OVER TEXAS. MODEL GUIDANCE HAS
NOT CHANGED MUCH SINCE THE LAST SET OF RUNS...EXCEPT FOR THE
UKMET...WHICH IS SHIFTED TO THE NORTH AND IS NOW THE RIGHT OUTLIER.
THE OFFICIAL FORECAST IS BETWEEN THE UKMET AND THE NOGAPS IN BEST
AGREEMENT WITH GUNS...AND LIES CLOSE TO THE RIGHT EDGE OF THE
ENVELOPE OF GUIDANCE.  THE NEW TRACK IS AN UPDATE OF THE PREVIOUS
TRACK THROUGH 36 HR...THEN SHIFTED A LITTLE SOUTHWARD THEREAFTER.

THE INTENSITY FORECAST IS SOMEWHAT PROBLEMATIC.  THE SHIPS MODEL HAS
20 KT OF SHEAR AFFECTING EMILY FROM WHICH IT FORECASTS WEAKENING...
BUT THIS SHEAR IS NOT APPARENT IN SATELLITE IMAGERY OR SATELLITE-
DERIVED WINDS FROM CIMSS.  A RECENT TRMM OVERPASS SHOWED NO
EVIDENCE OF AN OUTER EYEWALL...ALTHOUGH THERE WAS SOME OUTER
BANDING THAT COULD SOON WRAP UP INTO AN OUTER EYEWALL.
COMPLICATING MATTERS FURTHER...THE SHIPS MODEL SHOWS A MAXIMUM
POTENTIAL INTENSITY OF 155-160 KT...WHILE MAXIMUM POTENTIAL
INTENSITIES FROM COLA ARE CLOSER TO 135 KT.  THE INTENSITY FORECAST
FOLLOWS THE SCENARIO THAT THE MAXIMUM WINDS WILL OSCILLATE AROUND
135 KT AS THE HURRICANE GOES THROUGH INTERNAL CYCLES.  HOWEVER...IT
WOULD NOT BE A SURPRISE IF EMILY BECAME A CATEGORY FIVE HURRICANE
FOR SOME PART OF THE NEXT 24 HR.  EMILY SHOULD WEAKEN OVER
YUCATAN...BUT STILL BE A MAJOR HURRICANE OVER THE WESTERN GULF OF
MEXICO.

12 FT SEAS RADII WERE GREATLY REVISED IN THE SOUTHEASTERN QUADRANT
BASED ON OBSERVATIONS FROM NOAA BUOY 42058.  THE INITIAL WIND RADII
WERE SOMEWHAT REVISED BASED ON AIRCRAFT DATA.

FORECASTER BEVEN


FORECAST POSITIONS AND MAX WINDS

INITIAL      16/2100Z 16.8N  78.8W   135 KT
 12HR VT     17/0600Z 17.7N  81.2W   135 KT
 24HR VT     17/1800Z 19.1N  84.4W   135 KT
 36HR VT     18/0600Z 20.4N  87.7W   125 KT...INLAND
 48HR VT     18/1800Z 21.6N  90.7W   100 KT...OVER WATER
 72HR VT     19/1800Z 23.5N  96.0W   105 KT
 96HR VT     20/1800Z 25.0N 100.5W    65 KT...INLAND
120HR VT     21/1800Z 26.0N 104.5W    20 KT...INLAND DISSIPATING


$$
This weather bulletin was brought to you by:
www.nashvilleweather.net