Latest National Weather Service guidance and ensemble model runs for coastal Southern California emphasize persistent onshore flow and a strengthening marine layer, which are anchoring trader consensus on an 78–79°F high for Los Angeles on August 17 amid recent warm but moderated conditions. Afternoon sea breezes from the Pacific typically cap temperatures near downtown and airport sites below inland peaks, with recent days showing downtown readings in the mid-80s giving way to slight cooling as a coastal trough influences steering patterns. Key resolution thresholds hinge on official observations at primary stations, where even modest shifts in cloud cover or wind timing could separate the closely matched 76–77°F and 78–79°F bins. Updated NWS briefings and morning model outputs on August 17 will provide the final inputs before markets resolve.