000 WTPZ42 KNHC 032045 TCDEP2 Hurricane Lorena Discussion Number 8 NWS National Hurricane Center Miami FL EP122025 200 PM MST Wed Sep 03 2025 The Air Force Reserve reconnaissance aircraft that investigated Lorena made two passes through the center, measuring maximum 700-mb flight-level winds of 79 kt in the NE quadrant and a center dropsonde pressure of 985 mb with 7 kt of wind. The intensity is held at 70 kt based on the reconnaissance data. The data also confirmed that Lorena is rather small in size, with the aircraft data indicating a similar extent of the wind field as to what was previous estimated. Lorena could still intensify for another 6-12 hours while it remains over warm water and in low wind shear conditions. By 18 hours, the hurricane is expected to cross the 26C sea-surface temperature isotherm while southwesterly wind shear also begins to significantly increase. These conditions are expected to lead to rapid weakening beginning by Thursday afternoon. Only minor adjustments were made to the official intensity forecast. The official forecast is at the high end of the intensity guidance through 24 hours, and then lies closer to the middle of the guidance envelope thereafter. The track guidance hasn't changed too much, but the TVCE, GFEX, and other consensus models are a bit faster with the northeastward motion beyond 36 h, and the NHC track was sped up a bit after that time. Otherwise, only minor changes were made to the NHC track forecast. It should be noted that several models indicate a farther left track, with dissipation over water without making landfall. This scenario is possible if the hurricane rapidly weakens by Thursday night and starts to decouple due to the aforementioned increasing southwesterly shear. Regardless of which track scenario pans out, there is very high confidence that heavy rainfall amounts leading to significant flooding will occur in Baja California Sur, especially since the southwesterly upper-level winds favor deep convection to the right side of Lorena. Key Messages: 1. Heavy rainfall associated with Lorena will continue to impact Baja California Sur, moving into southwestern Sonora by Thursday. These rains are likely to cause life-threatening flash floods and mudslides. 2. Moisture from Lorena is likely to contribute to heavy rainfall concerns across Arizona and southern New Mexico through Saturday. Isolated to scattered instances of flash flooding are possible across Arizona into Saturday afternoon. 3. The center of Lorena is forecast to move parallel to, but offshore of, the southwest coast of the Baja California Peninsula through tonight, and then move closer to the west-central coast of the peninsula on Thursday. Regardless of the exact track, tropical storm conditions are likely along portions of the coast of Baja California Sur where a Tropical Storm Warning is in effect. Tropical storm conditions are also possible beginning Friday along the east coast of the Baja California peninsula, where a Tropical Storm Watch is in effect. 4. Life-threatening surf and rip current conditions will affect portions of the southern and western coasts of Baja California Sur during the next couple of days. FORECAST POSITIONS AND MAX WINDS INIT 03/2100Z 22.8N 112.4W 70 KT 80 MPH 12H 04/0600Z 23.6N 113.4W 80 KT 90 MPH 24H 04/1800Z 24.8N 113.9W 70 KT 80 MPH 36H 05/0600Z 26.0N 113.8W 55 KT 65 MPH 48H 05/1800Z 27.2N 113.3W 40 KT 45 MPH 60H 06/0600Z 28.4N 112.5W 35 KT 40 MPH 72H 06/1800Z 29.3N 111.8W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 07/1800Z...DISSIPATED $$ Forecaster Hagen/Brown
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