Issued at 300 AM CST Mon Sep 22 2025
000 WTPZ44 KNHC 220854 TCDEP4 Tropical Storm Narda Discussion Number 3 NWS National Hurricane Center Miami FL EP142025 300 AM CST Mon Sep 22 2025 The satellite presentation of Narda has shown some improvement since the previous advisory, with a well-defined curved band developing north of the center. Subjective Dvorak estimates from TAFB and SAB were 3.0/45 kt and 2.5/35 kt, respectively, while objective estimates from UW-CIMSS ranged from 37 to 43 kt. A blend of these data, along with the improved satellite appearance, supports raising the initial intensity to 40 kt for this advisory. Narda is moving west-northwestward, or 290 degrees, at 10 kt. A turn toward the west is expected later today as a mid-level ridge builds over northern Mexico. This westward motion is then forecast to continue for the next several days as the cyclone is steered by a strengthening ridge to its north and northwest. By late in the period, a mid-level low over southern California is expected to erode the eastern portion of the ridge, causing the cyclone to slow down and turn toward the northwest around day 5. The official forecast track has been adjusted slightly south of the previous one to better align with the latest consensus aids, and lies between the consensus guidance and the prior forecast. Narda will remain embedded within a moist air mass, over very warm waters, and in an environment of light to moderate east-northeasterly shear during the next couple of days. These factors should support steady strengthening, and Narda is forecast to become a hurricane Tuesday. By around 60 hours, easterly shear is expected to increase to 20–25 kt, which should slow the rate of intensification. By late in the forecast period, although the shear is forecast to relax, cooler sea surface temperatures and mid-level humidities falling below 50 percent should result in some weakening. The official intensity forecast remains near the upper end of the guidance envelope, close to the previous forecast, and most closely aligned with the SHIPS and HCCA aids. FORECAST POSITIONS AND MAX WINDS INIT 22/0900Z 15.4N 101.5W 40 KT 45 MPH 12H 22/1800Z 16.0N 103.0W 50 KT 60 MPH 24H 23/0600Z 16.3N 105.3W 60 KT 70 MPH 36H 23/1800Z 16.2N 107.5W 70 KT 80 MPH 48H 24/0600Z 16.2N 109.8W 80 KT 90 MPH 60H 24/1800Z 16.2N 112.3W 85 KT 100 MPH 72H 25/0600Z 16.2N 114.6W 90 KT 105 MPH 96H 26/0600Z 16.6N 119.3W 90 KT 105 MPH 120H 27/0600Z 17.8N 122.9W 80 KT 90 MPH $$ Forecaster Jelsema (CPHC)
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