Issued at 900 PM CST Sun Sep 21 2025
725 WTPZ44 KNHC 220232 TCDEP4 Tropical Storm Narda Discussion Number 2 NWS National Hurricane Center Miami FL EP142025 900 PM CST Sun Sep 21 2025 Narda hasn't become significantly better organized on satellite images over the past several hours. Convective banding features are not yet well defined, and the overall cloud pattern is still somewhat elongated from east to west. The system is currently experiencing moderate east-northeasterly shear. The current intensity estimate is held at 35 kt which is the mean of subjective Dvorak values from TAFB and SAB. The motion appears to be continuing toward the northwest, or around 305/9 kt. Global models show a mid-level ridge strengthening to the north of Narda during the next couple of days. This environmental flow evolution should cause the cyclone to turn toward the west with some increase in forward speed during the next 48 hours or so, which should keep the center to the south of the southern coast of Mexico. The official track forecast is a blend of the latest corrected and simple consensus predictions, TVCN and HCCA. This is very similar to the previous official forecast. Late in the forecast period, the ridge to the north weakens, which should result in a northward turn. Narda is expected to continue to be affected by moderate vertical wind shear for the next several days. However, the tropical cyclone should remain embedded in a very moist air mass and situated over a very warm oceans through the middle of the forecast period. The intensity model guidance is in good agreement that the system will strengthen into a hurricane within 36-48 hours and should continue to intensity until SSTs gradually lower later in the week. The official intensity forecast is similar to the latest Decay-SHIPS guidance and just slightly above the latest HCCA prediction. FORECAST POSITIONS AND MAX WINDS INIT 22/0300Z 15.3N 100.5W 35 KT 40 MPH 12H 22/1200Z 15.9N 101.7W 45 KT 50 MPH 24H 23/0000Z 16.3N 103.5W 55 KT 65 MPH 36H 23/1200Z 16.5N 105.4W 65 KT 75 MPH 48H 24/0000Z 16.4N 107.5W 75 KT 85 MPH 60H 24/1200Z 16.5N 109.8W 80 KT 90 MPH 72H 25/0000Z 16.6N 112.0W 85 KT 100 MPH 96H 26/0000Z 16.9N 116.8W 85 KT 100 MPH 120H 27/0000Z 17.7N 121.5W 85 KT 100 MPH $$ Forecaster Pasch
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