Cyclenall wrote:The reason must be because the wind flow changed as the winter pattern was setting into the tropics. I remember reading some old NHC advisories and they didn't expect this to become what it did at all.
Another Lenny would be very interesting to track.
"OBVIOUSLY...THE RAPID INTENSIFICATION OF THIS TROPICAL CYCLONE WAS
NOT ANTICIPATED. THIS AGAIN UNDERSCORES OUR LIMITED ABILITY TO
PREDICT INTENSITY CHANGE."
"AN UPPER LEVEL RIDGE OR ANTICYCLONE REMAINS OVER LENNY...SO FURTHER
INTENSIFICATION APPEARS LIKELY. THE BIGGEST QUESTION IS HOW LONG
WILL THE CURRENT RAPID STRENGTHENING CONTINUE? THE INTENSITY
FORECAST CALLS FOR FURTHER STRENGTHENING FOR 24 HOURS FOLLOWED BY A
LEVELING OUT. ALTHOUGH MAJOR NOVEMBER HURRICANES ARE NOT UNHEARD
OF...THEY ARE UNCOMMON ENOUGH THAT I WILL NOT FORECAST LENNY TO
BECOME ONE JUST YET."
"HERE WE GO AGAIN! REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER
AIRCRAFT INDICATE LENNY IS STRENGTHENING WITH A MINIMUM CENTRAL
PRESSURE OF 971 MB AND MAXIMUM 850 MB WINDS OF 109 KT. THE PLANE
ALSO REPORTED A 45 NM WIDE EYE. ALTHOUGH NO EYE IS VISIBLE IN
SATELLITE IMAGERY...THE CLOUD TOPS NEAR THE CENTER ARE -80C TO -85C
AND SATELLITE INTENSITY ESTIMATES ARE AS HIGH AS 102 KT. THE INITIAL
INTENSITY IS SET TO 85 KT...AND THIS MAY BE A BIT CONSERVATIVE."
"THE SIGNIFICANT EVENT OF THE DAY IS THE UNEXPECTED INTENSIFICATION
OF LENNY...INDICATING THAT THERE IS LITTLE SKILL IN FORECASTING
RAPID INTENSITY CHANGES. THE CENTRAL PRESSURE EXTRAPOLATED FROM 700
MB HAS FALLEN TO 927 MB WHILE A DROP MEASURED 934 MB. THE
FLIGHT-LEVEL WINDS HAVE INCREASED TO 149 KNOTS. THE MEAN BOUNDARY
LAYER WINDS FROM DROPSONDES ARE 155 KNOTS AND PEAK WINDS REACHED 180
KNOTS AT THE 891-MB LEVEL A COUPLE OF HOURS AGO. BASED ON THAT
INFORMATION...INITIAL INTENSITY WAS ADJUSTED TO 130 KNOTS."
"...WEAKENING IS INDICATED AS LENNY MOVES TOWARD A LESS
FAVORABLE UPPER-LEVEL WIND ENVIRONMENT. IF THE THERMODYNAMICS ARE
PROPERLY ESTABLISHED...A PARAMETER I DO NOT KNOW TO FORECAST...THE
HURRICANE COULD OVERCOME THE SHEARING EFFECTS AND REMAIN STRONG A
LITTLE BIT LONGER."
"ALSO THE
FORECAST TRACK IS A LITTLE SLOWER TO ACCOUNT FOR THE UNCERTAINTY IN
LOCATION AND MOTION AND FOR THE PERSISTANT NORTH BIAS THAT ALL OF
THE GLOBAL MODELS HAVE DISPLAYED DURING THE PAST SEVERAL DAYS.
MAYBE NUMERICAL MODELS ARE NOT ABLE TO MOVE A SLOW MOVING TROPICAL
CYCLONE SOUTHWARD IN THE DEEP TROPICS??"
Mark,Brent and other members who are already thinking about 2008,I think this will have a good chance to do something,but of course time will tell.
