Saturday, August 26, 2023

Franklin Now A Hurricane (Category 1) No Longer A Threat To Our Region






































965 
WTNT33 KNHC 270246
TCPAT3

BULLETIN
Hurricane Franklin Advisory Number  26
NWS National Hurricane Center Miami FL       AL082023
1100 PM AST Sat Aug 26 2023

...FRANKLIN FORECAST TO BECOME A MAJOR HURRICANE BY LATE SUNDAY...

SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.9N 68.2W
ABOUT 250 MI...400 KM NE OF GRAND TURK ISLAND
ABOUT 615 MI...990 KM SSW OF BERMUDA
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES

WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.

Interests in Bermuda should monitor the progress of this system.

DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the center of Hurricane Franklin was 
located near latitude 23.9 North, longitude 68.2 West. Franklin is 
moving toward the northwest near 8 mph (13 km/h). A turn toward the 
north-northwest is expected on Sunday, followed by a northward 
motion into early next week.

Data from the Air Force and NOAA Hurricane Hunters indicate that 
maximum sustained winds are near 85 mph (140 km/h) with higher 
gusts. Significant strengthening is expected during the next couple 
of days, and Franklin is forecast to become a major hurricane by 
late Sunday.

Hurricane-force winds extend outward up to 25 miles (35 km) from the 
center and tropical-storm-force winds extend outward up to 140 miles 
(220 km). NOAA buoy 41046, located several hundred miles east of the 
Bahamas, recently reported a sustained wind of 49 mph (79 km/h) and 
a gust to 58 mph (93 km/h).

The estimated minimum central pressure based on dropsonde data is 
975 mb (28.80 inches).

HAZARDS AFFECTING LAND
----------------------
SURF:  Swells generated by Franklin are expected to begin affecting
Bermuda by Sunday night. These swells are also likely to cause
life-threatening surf and rip current conditions late this weekend
through early next week along portions of the east coast of the
United States. Please consult products from your local weather
office.

NEXT ADVISORY
-------------
Next complete advisory at 500 AM AST.

$$
Forecaster Reinhart


221 
WTNT43 KNHC 270247
TCDAT3

Hurricane Franklin Discussion Number  26
NWS National Hurricane Center Miami FL       AL082023
1100 PM AST Sat Aug 26 2023

The eye of Franklin has been obscured in conventional satellite 
imagery by deep convective bursts within its southern eyewall during 
the past several hours. At times, there has been some disruption of 
the inner core convection by drier air wrapping around the eastern 
and northern portions of the circulation. Both the Air Force and 
NOAA Hurricane Hunters investigated Franklin tonight and provided 
useful data to analyze the storm. Tail Doppler radar data from the 
NOAA aircraft reveal better vertical alignment of Franklin's vortex, 
although there is still a bit of tilt with height. Peak SFMR wind 
retrievals from both aircraft support an initial intensity of 75 kt, 
and the latest dropsonde data indicate the surface pressure has 
fallen to 975 mb. 

Conditions appear favorable for some significant strengthening of 
Franklin during the next couple of days. The deep-layer shear is 
forecast to continue decreasing over the cyclone while it traverses 
very warm SSTs greater than 29 deg C. The hurricane could be prone 
to more rapid fluctuations in intensity given its small inner core, 
and some of the rapid intensification (RI) guidance, particularly 
DTOPS, suggests there are well above average chances that Franklin 
could undergo RI during the next 48 h. Thus, the updated intensity 
forecast is raised in the near term, bringing Franklin to major 
hurricane strength in 24 h with a peak intensity of 115 kt on 
Monday. This lies near HCCA and IVCN, but below some of the regional 
hurricane models (HAFS and COAMPS-TC). Weakening is forecast at 
days 4 and 5 as Franklin encounters increased shear over cooler 
SSTs, but its wind field is expected to grow as it moves deeper into 
the mid-latitudes.

The aircraft fixes indicate Franklin has continued to deviate left 
of the forecast track, and its initial motion is northwestward at 7 
kt. The near-term track forecast has been adjusted west of the 
previous one based on Franklin's continued northwestward motion. A 
broad high pressure ridge to the east of Franklin should steer the 
hurricane more north-northwestward and northward during the next 
couple of days. Later in the period, a deep-layer trough is expected 
to move off the U.S. east coast, and most global models (except the 
ECMWF) show Franklin becoming captured within the southwesterly flow 
ahead of the trough and accelerating northeastward. The NHC forecast 
track still shows the core of Franklin passing west and north of 
Bermuda, but interests there should continue to monitor the latest 
NHC forecast updates. By day 5, interaction with the upper trough 
could bring about the start of extratropical transition.  


FORECAST POSITIONS AND MAX WINDS

INIT  27/0300Z 23.9N  68.2W   75 KT  85 MPH
 12H  27/1200Z 24.9N  68.9W   85 KT 100 MPH
 24H  28/0000Z 26.2N  69.8W  100 KT 115 MPH
 36H  28/1200Z 27.6N  70.4W  110 KT 125 MPH
 48H  29/0000Z 29.2N  70.4W  115 KT 130 MPH
 60H  29/1200Z 30.8N  69.9W  115 KT 130 MPH
 72H  30/0000Z 32.5N  68.9W  105 KT 120 MPH
 96H  31/0000Z 35.8N  63.7W   90 KT 105 MPH
120H  01/0000Z 41.0N  52.5W   75 KT  85 MPH

$$
Forecaster Reinhart

Late August Rainstorm Update Two