487 WTNT41 KNHC 011500 TCDAT1 Tropical Storm Martin Discussion Number 1 NWS National Hurricane Center Miami FL AL162022 1100 AM AST Tue Nov 01 2022 The occluded low over the central North Atlantic has developed deep convection over its center, while the frontal boundaries have become displaced a long distance to its east and north. At the same time, FSU Cyclone Phase Space analyses suggest that the system has developed a non-frontal warm core. Given these changes, the system has evolved into a tropical cyclone. The ASCAT scatterometer just observed the system and indicated that the intensity is currently at 45 kt with a large area of 35 kt-plus winds. Thus the system is now a tropical storm and given the name Martin. The system is moving toward the east-northeast around 8 kt, as it is embedded in the mid-latitude westerlies in a split in the jet stream with faster westerlies both poleward and equatorward of the system. Martin should turn toward the northeast at an increasingly rapid forward speed during the next two days. The official track forecast is based upon the consensus (TVCN and HCCA) of the tightly clustered global and hurricane dynamical models. In about three days, Martin should decelerate as it merges with a developing extratropical low to its north. For the intensity, even though the SSTs are a lukewarm 25C, the upper-level temperatures are quite cold given that Martin is embedded within a deep and vertically stacked cyclone. This vertical temperature structure should enable deep convection to continue, even while the mid-level moisture is only marginally ample. The vertical shear is 20-25 kt out of the southwest, but the effects of this moderate shear are tempered by Martin moving in the same direction as the shear vector. Bottom line is that despite the month being November, Martin is expected to develop into a hurricane at high latitudes. The official intensity prediction steadily strengthens the system through 48 hr, which matches a consensus of the statistical, global, and hurricane dynamical models. Around 48 hr, Martin should transition into a powerful extratropical low as a cold front reaches near the center of the system. In about three days, post-tropical Martin should be merging with an developing extratropical system to its north but still be containing hurricane-force winds. FORECAST POSITIONS AND MAX WINDS INIT 01/1500Z 35.3N 55.9W 45 KT 50 MPH 12H 02/0000Z 35.4N 53.9W 50 KT 60 MPH 24H 02/1200Z 36.1N 50.7W 60 KT 70 MPH 36H 03/0000Z 38.7N 46.4W 70 KT 80 MPH 48H 03/1200Z 43.8N 40.0W 75 KT 85 MPH...POST-TROP/EXTRATROP 60H 04/0000Z 51.5N 34.6W 75 KT 85 MPH...POST-TROP/EXTRATROP 72H 04/1200Z 56.0N 34.9W 70 KT 80 MPH...POST-TROP/EXTRATROP 96H 05/1200Z...DISSIPATED $$ Forecaster Landsea