Issued at 1100 PM AST Fri Sep 26 2025
991 WTNT43 KNHC 270238 TCDAT3 Hurricane Humberto Discussion Number 10 NWS National Hurricane Center Miami FL AL082025 1100 PM AST Fri Sep 26 2025 Humberto has continued to intensify rapidly this evening. The eye temperature has increased to 15C and the eyewall white ring (-73C) is nearly closed. A 2137 UTC WSFM-1 HiRes microwave pass indicated that a concentric ring was developing about 65 nm from the eye. The initial intensity is raised to 125 kt and is close to the UW-CIMSS ADT of T6.4 and above the constrained subjective Dvorak intensity estimates from TAFB and SAB. All intensity contributions, low shear, warm waters, and ample mid-level moisture, appear conducive for Humberto to intensify rapidly during the next 12-24 hours. DTOPS guidance indicates a high probability of RI during the next 12-24 hours, and the latest official intensity forecast follows suit, bringing Humberto to a peak intensity of 140 kt Saturday night. By the 36 hour period, however, inner-core fluctuations as a result of eyewall replacement cycles (ERC) are possible, and it's difficult to forecast the exact timing. It's worth mentioning, however, that the UW-CIMSS M-PERC (Microwave-based Probability of Eyewall Replacement Cycle) statistical model is predicting a 61 percent of onset. By mid-next week, increasing vertical shear spreading over Humberto should induce a gradual weakening trend. At the same time, while it passes west of Bermuda, a significant expansion in the surface wind field will likely occur. The NHC intensity forecast is just above the previous forecast through the 36 hour period, and closely follows a blend of the HCCA consensus and the HAFS/HWRF/HMON hurricane models. Humberto has taken a trochoidal jog to the left of the track this evening, likely due to the rapid intensification event. The initial motion is estimated to be slightly south of due west, or 265/6 kt. Humberto is expected to move slowly toward the west or west-northwest during the next day or so in the easterly steering flow provided by mid-tropospheric high pressure located to the north of the cyclone and just east of Bermuda. Around the 48 hour period, or Sunday evening, a northwestward turn with some reduction in forward speed is forecast while the above-mentioned high pressure weakens and shifts eastward. By day 4, Humberto should commence a rather abrupt turn northward and northeastward in response to a major shortwave upper-level trough amplifying and moving out of northeastern Canada and into the northwestern Atlantic. The official track forecast is located just to the left of the previous advisory, primarily due to the initial motion left of track, and lies between the HCCA corrected consensus and the Google DeepMind ensemble model. NOAA buoy 41044, located about 38 n mi southwest of the center, has reported falling pressure,sustained tropical-storm-force winds, gusts just below hurricane-force and 17 ft seas. FORECAST POSITIONS AND MAX WINDS INIT 27/0300Z 22.1N 58.7W 125 KT 145 MPH 12H 27/1200Z 22.2N 59.8W 135 KT 155 MPH 24H 28/0000Z 22.7N 61.6W 140 KT 160 MPH 36H 28/1200Z 23.6N 63.5W 135 KT 155 MPH 48H 29/0000Z 24.8N 65.3W 130 KT 150 MPH 60H 29/1200Z 26.2N 67.0W 125 KT 145 MPH 72H 30/0000Z 27.9N 68.2W 115 KT 130 MPH 96H 01/0000Z 32.1N 68.2W 100 KT 115 MPH 120H 02/0000Z 36.0N 62.0W 90 KT 105 MPH $$ Forecaster Roberts
NHC Atlantic
