ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM Tropical Storm Cristina Discussion Number 6 NWS National Hurricane Center Miami FL EP052020 1000 PM CDT Tue Jul 07 2020 Since the previous advisory, Cristina's well-defined low-level center became briefly exposed for a couple of hours, likely resulting in a slight spin-down of the vortex. However, deep convection has recently redeveloped over and southwest of the center, so the intensity will be held at 40 kt for this advisory, which is a blend of TAFB and SAB subjective satellite classifications, and the most recent downward-trending UW-CIMSS ADT estimate of T2.9/43 kt. The initial motion estimate is 300/13 kt. There is no significant change to the previous forecast track or reasoning. The latest NHC model guidance remains in excellent agreement on Cristina moving west-northwestward south of a nearly stationary deep-layer subtropical ridge for the next 5 days. The new NHC forecast track is a tad north of the previous advisory track, and lies close to the tightly packed simple and corrected consensus models. High-resolution GOES-16 visible satellite imagery indicates that Cristina's center has been moving closer to the center of the synoptic-scale upper-level anticyclone where the vertical wind shear should be lower. The recent burst of deep convection near the center could the beginning stages of more significant strengthening owing to the lower shear, high mid-level humidity near 80 percent, and sea-surface temperatures (SSTs) near 29C. Therefore, steady strengthening is forecast for the next 60 h while the cyclone remains over warm SSTs, and a period of rapid intensification (RI) is still possible during the next couple of days. By 72 h and beyond, however, Cristina will be moving over sub-26 deg C SSTs that will decrease to about 22C by 120 h, with the much cooler water inducing steady weakening on days 4-5. The NHC intensity forecast is similar to the IVCN intensity guidance through 36 hours, and then is slightly higher than the guidance in order to maintain continuity with the previous intensity forecast and also due to the possibility of RI occurring. FORECAST POSITIONS AND MAX WINDS INIT 08/0300Z 13.8N 105.3W 40 KT 45 MPH 12H 08/1200Z 14.7N 106.7W 50 KT 60 MPH 24H 09/0000Z 15.9N 108.6W 55 KT 65 MPH 36H 09/1200Z 17.0N 110.4W 65 KT 75 MPH 48H 10/0000Z 17.8N 112.2W 75 KT 85 MPH 60H 10/1200Z 18.8N 114.2W 80 KT 90 MPH 72H 11/0000Z 19.8N 116.5W 80 KT 90 MPH 96H 12/0000Z 21.4N 121.6W 65 KT 75 MPH 120H 13/0000Z 22.1N 127.0W 50 KT 60 MPH $$ Forecaster Stewart NNNN