Issued at 200 AM MST Thu Sep 25 2025
000 WTPZ44 KNHC 250845 TCDEP4 Hurricane Narda Discussion Number 15 NWS National Hurricane Center Miami FL EP142025 200 AM MST Thu Sep 25 2025 Narda is holding steady this morning despite persistent 20 kt of northeasterly vertical wind shear. Recent satellite imagery shows a well-defined central dense overcast (CDO) with cloud tops near –90 C, along with a curved band wrapping into the center from the southwest. The latest subjective Dvorak intensity estimates from TAFB and SAB are both T4.5/77 kt, while objective intensity estimates from UW-CIMSS range between 61 and 72 kt. Given the improved satellite presentation over the past few hours and these estimates, the initial intensity is held at 80 kt. The initial motion is toward the west near 280/13 kt, and this forward speed is expected to remain steady through 48 h (Friday night). After that time, Narda should begin to slow down as it turns west-northwestward, then northwestward, and eventually northward through the weekend in response to a weakness developing in the subtropical ridge. There remains considerable spread in the guidance regarding the timing of this northward turn. The ECMWF shows a later turn near 72 h (Saturday night), while the consensus aids indicate an earlier turn, around 60 h (during the day Saturday). A later turn would keep Narda over warmer waters longer and allow it to maintain strength, whereas an earlier turn would move the system over cooler waters sooner and result in quicker weakening. The official track forecast is slightly to the left of the previous one after 60 h, reflecting a blend of the prior forecast and the consensus aids. Only slight weakening is forecast during the next 12-24 h while the northeasterly shear persists. Between 24 and 48 h (tonight into Friday night), the shear is expected to ease to more moderate levels while Narda remains over warm waters with plenty of mid- to upper-level moisture, which should allow for a period of re-strengthening. This forecast lies near the middle to upper portion of the guidance envelope during that brief window (24–36 h). By around 60 h (Saturday), sea-surface temperatures along the track are forecast to fall below 26 C, and steady weakening is forecast thereafter. Narda is expected to fall below hurricane strength by the end of the weekend and become a post-tropical remnant low by day 5 (Monday night). The latest intensity forecast is very similar to the previous one and remains near the middle to upper portion of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 25/0900Z 15.6N 114.8W 80 KT 90 MPH 12H 25/1800Z 15.8N 116.8W 75 KT 85 MPH 24H 26/0600Z 16.3N 119.5W 80 KT 90 MPH 36H 26/1800Z 17.0N 122.0W 85 KT 100 MPH 48H 27/0600Z 17.5N 124.0W 85 KT 100 MPH 60H 27/1800Z 18.2N 125.3W 80 KT 90 MPH 72H 28/0600Z 19.2N 125.8W 65 KT 75 MPH 96H 29/0600Z 21.2N 125.6W 40 KT 45 MPH 120H 30/0600Z 23.0N 124.7W 30 KT 35 MPH...POST-TROP/REMNT LOW $$ Forecaster Gibbs (CPHC)
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