| Track: https://www.nhc.noaa.gov/refresh/graphics_at3+shtml/?cone#contents Again, this is not the one over Africa that still has a 70% chance within 5 days. (Atlantic outlook: https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=5) Tropical Storm Gabrielle Discussion Number 3 NWS National Hurricane Center Miami FL AL082019 500 AM AST Wed Sep 04 2019 A late-arriving ASCAT-C scatterometer pass revealed peak surface winds of 33 kt in the northwestern quadrant, and satellite imagery since then indicates a marked increase in the deep convection, albeit sheared to the northeast of the well-defined low-level center noted in the scatterometer data. Based on these wind data and a satellite intensity estimate of T2.5/35 kt from TAFB and UW-CIMSS ADT, the depression has been upgraded to Tropical Storm Gabrielle, the seventh named storm of the 2019 Atlantic hurricane season. The initial motion is 310/09 kt. The initial position was adjusted slightly to the southwest of the previous positions based on the aforementioned scatterometer data. This has resulted in the new forecast track being shifted a little to the left of the previous advisory track at all forecast times. For the next 5 days, Gabrielle is forecast to move generally northwestward toward a break in the Bermuda-Azores high pressure ridge located between 40W-50W longitude. The official forecast track lies close to a blend of the tightly packed consensus models TVCN, TVCX, and NOAA-HCCA. During the entire forecast period, Gabrielle is forecast to remain in a marginally conducive environment characterized by moderate southwesterly vertical wind shear of 15-20 kt, SSTs of 26-27 deg C, and dry mid-level air with humidity values less than 50 percent. As a result, only slight strengthening is forecast through 72 hours. The new NHC intensity forecast is similar to the previous advisory, and closely follows the HCCA consensus intensity model. FORECAST POSITIONS AND MAX WINDS INIT 04/0900Z 19.6N 33.6W 35 KT 40 MPH 12H 04/1800Z 20.3N 34.4W 40 KT 45 MPH 24H 05/0600Z 21.1N 35.3W 40 KT 45 MPH 36H 05/1800Z 22.1N 36.4W 45 KT 50 MPH 48H 06/0600Z 23.4N 37.7W 45 KT 50 MPH 72H 07/0600Z 27.5N 41.0W 50 KT 60 MPH 96H 08/0600Z 31.5N 44.5W 50 KT 60 MPH 120H 09/0600Z 35.5N 47.2W 50 KT 60 MPH $$ Forecaster Stewart Tropical Storm Gabrielle Advisory Number 3 NWS National Hurricane Center Miami FL AL082019 500 AM AST Wed Sep 04 2019 ...DEPRESSION STRENGTHENS INTO TROPICAL STORM GABRIELLE OVER THE OPEN ATLANTIC OCEAN... SUMMARY OF 500 AM AST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...19.6N 33.6W ABOUT 680 MI...1090 KM WNW OF THE CABO VERDE ISLANDS ABOUT 1330 MI...2140 KM SSW OF THE AZORES MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H PRESENT MOVEMENT...NW OR 310 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM AST (0900 UTC), the center of Tropical Storm Gabrielle was located near latitude 19.6 North, longitude 33.6 West. Gabrielle is moving toward the northwest near 10 mph (17 km/h,) and this general motion is forecast to continue through Friday, with an increase in forward speed expected late in the week. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Some slight strengthening is forecast during the next 48 hours. Tropical-storm-force winds extend outward up to 90 miles (150 km) from the center. The estimated minimum central pressure is 1005 mb (29.68 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 1100 AM AST. $$ Forecaster Stewart |