Good day everyone!
Tropical Disturbance INVEST 91L continues to spin this morning in the south central GOMEX. As of the current TWO from the NHC, the probability of 91L becoming a tropical cyclone during the next 48 hours has increased to 50% (MEDIUM).
Satellite loop imagery this morning still shows a disorganized system, albeit cyclonic rotation has tightened over the past 24 hours. All of the heavy convection remains east and SE of the center, due to 20-25 knots of westerly wind shear over the system, as indicated in the current wind shear map from CIMSS. Satellite images are linked so you may play the loop.
Based on analysis of satellite floater loop channel IR2, I have placed the center near 25.0N;89.0W. However, current 925 mb vorticity satellite information from PSU e-WALL indicates the vort max to be located just on the very extreme edge of the convection.
91L is currently still located in a weak steering regime, and may remain quasi-stationary most of the day, and may even attempt a cyclonic loop before heading NE. Beginning later tonight, early tomorrow, this system should begin to move toward the NNE then NE as an approaching trof makes its presence known.
The exact location of where the “center” comes ashore, will depend on how long this remains stationary, and how strong it becomes. Should it stay where it is longer, a track on the right side of the guidance package could be in order. However, based on the current run of the forecast steering layers maps, model guidance at the moment looks the most plausible, with the center coming ashore around the Big Bend area of Florida, or slightly north.
As far as strength goes, wind shear has continued to slowly decrease over the system, however not enough right now for the LLC to become stacked under the convection. Indications from the GFS and CMC show wind shear to relax over the next 24 hours, with a small upper level anticyclone developing, however with a shear zone remaining very close to the western periphery of this disturbance. Never the less, this may be just enough for 91L to attain depression status, to possibly minimal Sub-tropical storm just prior to coming ashore.
Portions of the Florida Peninsula may pick up 4″-7″ inches of precipitation, however heavier amounts could be experienced in heavier, slower moving thunderstorm cells.
The West Central Florida area is currently under a FLOOD WATCH:
FLOOD WATCH NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL 521 AM EDT WED JUN 5 2013 ...FLOOD WATCH IN EFFECT FOR PORTIONS OF WEST CENTRAL AND SOUTHWEST FLORIDA THROUGH THURSDAY EVENING... .WIDESPREAD RAINFALL TOTALS OF 3 TO 5 INCHES ARE LIKELY WITH LOCALLY HIGHER AMOUNTS POSSIBLE THROUGH THURSDAY EVENING AS AN AREA OF LOW PRESSURE IN THE CENTRAL GULF OF MEXICO HEADS NORTH THEN NORTHEAST TOWARD THE FLORIDA GULF COAST. FLZ049>052-055>057-060>062-065-070000- /O.CON.KTBW.FA.A.0001.000000T0000Z-130607T0000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ PASCO-PINELLAS-HILLSBOROUGH-POLK-MANATEE-HARDEE-HIGHLANDS- SARASOTA-DESOTO-CHARLOTTE-LEE- INCLUDING THE CITIES OF...NEW PORT RICHEY...ZEPHYRHILLS... CLEARWATER...ST. PETERSBURG...BRANDON...TAMPA...LAKELAND... WINTER HAVEN...BRADENTON...WAUCHULA...SEBRING...AVON PARK... NORTH PORT...SARASOTA...VENICE...ARCADIA...PORT CHARLOTTE... PUNTA GORDA...CAPE CORAL...FORT MYERS 521 AM EDT WED JUN 5 2013 ...FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY EVENING... THE FLOOD WATCH CONTINUES FOR * PORTIONS OF SOUTHWEST FLORIDA AND WEST CENTRAL FLORIDA... INCLUDING THE FOLLOWING AREAS...IN SOUTHWEST FLORIDA... CHARLOTTE AND LEE. IN WEST CENTRAL FLORIDA...DESOTO...HARDEE... HIGHLANDS...HILLSBOROUGH...MANATEE...PASCO...PINELLAS...POLK AND SARASOTA. * THROUGH THURSDAY EVENING * WIDESPREAD RAINFALL TOTALS OF 3 TO 5 INCHES ARE LIKELY...WITH LOCALLY HIGHER AMOUNTS POSSIBLE THROUGH THURSDAY EVENING. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FLOOD WATCH MEANS THAT FLOODING IS POSSIBLE DURING THE NEXT 24 TO 48 HOURS. RESIDENTS LIVING IN FLOOD PRONE AREAS SHOULD TAKE ACTION TO PROTECT PROPERTY.
Some minor coastal flooding may occur at the time of high tide along portions of the watch area, with some minor beach erosion, as waves will be running 7-10 ft near the coast as the system makes its closest approach.
I will be monitoring 91L during the day, and should have another update later this evening, unless an update is warranted sooner.
Elsewhere, I am monitoring a tropical wave in the CATL, located near 10.0N;41.0W. The wave is currently moving to the west at 15-20 mph. Currently, upper level winds are semi-conducive, however this will very likely run into wind shear as it approaches 50W Longitude in the next 72 hours. I will continue to monitor this for any significant changes during the next 72 hours.
Elsewhere, Tropical Storm formation is not expected during the next 5-7 days.
Have a blessed day!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)