Issued at 800 PM MST Wed Sep 24 2025
630 WTPZ44 KNHC 250251 TCDEP4 Hurricane Narda Discussion Number 14 NWS National Hurricane Center Miami FL EP142025 800 PM MST Wed Sep 24 2025 Narda has weakened slightly due to persistent 20–25 kt northeasterly vertical wind shear. However, more recent satellite imagery shows an expanding burst of very cold convection, with cloud tops to –90 C redeveloping over the center and a curved band wrapping in from the southwest. The latest subjective Dvorak classifications from TAFB and SAB are lower, ranging between T4.0/65 kt and T4.5/77 kt, while objective intensity estimates from UW-CIMSS are in the 57–68 kt range. In light of the improved convective presentation during the past few hours, the initial intensity is only lowered slightly, to 80 kt for this advisory. The initial motions is toward the west at about 270/9 kt, steered by a subtropical ridge positioned to its north. The track guidance remains in good agreement on a general westward motion through about 48 h. Between 48 and 60 h, Narda should turn west-northwestward, followed by a northwestward motion from 60 to 72 h. Beyond 72 h, a gradual turn toward the north-northeast is forecast as a weakness develops in the ridge in response to an upper-level low over California and a digging shortwave trough over the northeast Pacific. By days 4 and 5, Narda should continue north-northeastward. The NHC forecast is close to the previous forecast, aligning closely with multi-model consensus aids. Only slight weakening is forecast during the next day or so as the vertical shear persists. By Friday, the shear is expected to ease to more moderate levels while Narda remains over warm waters with a moist environment, which should allow for some re-strengthening. The northwestward track between 60 and 72 h may also keep the system over warmer waters a little longer, potentially delaying weakening. However, by 72–96 h, Narda is forecast to encounter cooler waters and a drier mid-level airmass, leading to a steady weakening trend. The cyclone is expected to become post-tropical by day 5 or early next week. The latest intensity forecast is very similar to the previous forecast and remains near the middle to upper portion of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 25/0300Z 15.1N 113.2W 80 KT 90 MPH 12H 25/1200Z 15.4N 115.2W 75 KT 85 MPH 24H 26/0000Z 15.7N 117.7W 75 KT 85 MPH 36H 26/1200Z 16.3N 120.2W 75 KT 85 MPH 48H 27/0000Z 16.9N 122.3W 85 KT 100 MPH 60H 27/1200Z 17.7N 124.1W 85 KT 100 MPH 72H 28/0000Z 18.6N 124.9W 75 KT 85 MPH 96H 29/0000Z 20.4N 124.6W 55 KT 65 MPH 120H 30/0000Z 21.8N 124.0W 40 KT 45 MPH...POST-TROPICAL $$ Forecaster Gibbs (CPHC)
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