ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM 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 NNNN