000 WTNT45 KNHC 021438 TCDAT5 TROPICAL STORM DOLLY DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL052014 1000 AM CDT TUE SEP 02 2014 North-northwesterly vertical shear continues to affect the tropical storm, and the low-level center is located near the northwestern edge of a large mass of deep convection. Arc clouds are also noted to be propagating northward from the system which is indicative of the presence of some dry air at mid levels. Based on observations from the aircraft mission from earlier this morning, the current intensity is held at 45 kt, which is a little above the latest Dvorak estimates. Another Air Force Hurricane Hunter mission into Dolly is scheduled in a few hours to check the intensity. Since the system has been able to intensify overnight in spite of the shear, some additional strengthening is certainly possible before landfall. Weakening after the center moves inland could be more rapid than indicated here, due to the mountainous terrain of northeastern Mexico. The motion has been somewhat faster than earlier estimates and is now near 300/14 kt. A mid-level ridge to the north of Dolly should cause a continued west-northwestward motion for the next 24 hours or so and, based on the faster initial motion, the center is likely to cross the coast somewhat earlier than indicated in previous advisories. The current official track forecast is a little ahead of the model guidance but still shows a decrease in forward speed through 36 hours. The primary threat from Dolly will come from heavy rainfall, with precipitation totals possibly approaching 10 inches in a few locations. These rains will likely cause flash flooding and mud slides in regions of mountainous terrain. This threat will continue even after the center moves inland. FORECAST POSITIONS AND MAX WINDS INIT 02/1500Z 23.4N 96.5W 45 KT 50 MPH 12H 03/0000Z 24.0N 97.5W 50 KT 60 MPH 24H 03/1200Z 24.5N 99.0W 40 KT 45 MPH...INLAND 36H 04/0000Z 24.8N 100.5W 25 KT 30 MPH...INLAND 48H 04/1200Z...DISSIPATED $$ Forecaster Pasch