Halley (17), a year 13 pupil at Bayfield High School, lined up with fellow front-marker and clubmate Dalise Sanderson in atrocious conditions for the annual handicap race.
For the first two laps, Halley held her own, threatening to make a mockery of her handicap and record a convincing victory.
But a mile (1600m) can seem a long way, particularly in gusty wet conditions. As the weather began to take a toll on Halley going into the final two laps, she started to fade. Sanderson came back at her and opened up a 40m lead, while appearing to make running in the conditions easy.
''I thought I was gone,'' Halley said after the race.
''Then instinct kicked in. I guess it was from the genes I got from my dad.''
Halley said she surprised herself with the manner in which she was able to come back at Sanderson on the final lap, and take the lead coming down the home straight.
Her only concern was sensing Otago 1500m and 3000m champion Bella Bloomfield (Hill City) coming up fast behind her.
''I just kicked in another gear and hoped against hope,'' she said.
''When I got to the line I just burst into smile. I can't stop.''
Halley's father, Brent, a former Otago marathon and middle-distance champion who won the Caledonian mile three years ago, was on hand to witness his daughter win her first Otago title.
Halley recorded an actual mile time of 6min 45.73sec, and second-placed Sanderson posted 6min 47.97sec. Bloomfield was third with an actual time of 5min 35.50sec.
Less an an hour after winning the 1500m in a smart time - given the deteriorating conditions - of 4min 1.87sec, Otago junior middle-distance champion Sam Bremer (Hill City), clocked the fastest time in the mile, recording 4min 49.85sec.
Highlights from other events on the programme
• Rebeka Kiwara (Wellington) won the open women's 100m and 200m double. Kiwara clocking 13.26sec into the rain and wind to win the 100m, and held out Harriet Donald (Wanganui) in a stride-for-stride battle down the home straight to win the 200m.
• Ben Anderson (Caversham) led throughout to win the 400m in 50.86sec.
• It was one-way traffic for Jonah White (Caversham) on his way to victory in the 5000m. White clocked 16min 48.83sec.
• Tori Peeters (Taieri) overcame demanding conditions to win the senior women's javelin with 45.26m.
• Todd Bates won the senior men's hammer with a first-round distance of 46.30m.
