Hales scored his runs from just 38 deliveries faced - including four fours and five sixes - as the Outlaws raced to their target after Yorkshire, who had opted to bat first, had posted 132 for seven.
Northamptonshire also booked their place in the last eight with a comfortable win over Glamorgan at the Swalec Stadium, Cardiff.
Fine displays from Cameron White and Mohammed Azharullah enabled the Steelbacks to win their top-of-the-table clash in the Midlands, Wales and West Group by six wickets, with nine balls to spare.
Glamorgan, unbeaten at home until this clash, will have to beat Gloucestershire at Cardiff on Tuesday to have any chance of reaching the last eight.
White scored 71 from 48 balls while Azharullah recorded figures of four wickets for 16 runs from his four overs as Glamorgan were restricted to 125 for nine.
Surrey are not completely over the line but an unbroken partnership of 79 in 10 overs between Azhar Mahmood and Zafar Ansari swept them to a five-wicket victory against Kent which all but guaranteed them a quarter-final place.
Mahmood thumped Matt Coles for a four and six from successive balls in a decisive 19th over that cost 17 runs as Surrey overhauled Kent's 139 for four with five balls to spare.
Despite earlier collapsing alarmingly from a seemingly comfortable 47 for no wicket to 61 for five inside five overs, Surrey surged to a sixth win in their ninth South Group match thanks to brilliant batting from the veteran Mahmood and the 21-year-old Ansari.
Mahmood, the 38-year old former Pakistan all-rounder who rejoined Surrey last winter after five seasons at Kent, finished on 47 not out from just 31 balls, with three sixes and three fours in all.
An inspired spell of pace bowling by Anthony Ireland left Derbyshire's quarter-final hopes hanging by a thread when Leicestershire thrashed them by 79 runs at Derby.
Ireland took four wickets for 11 runs in his four overs, which contained 14 dot balls, as Derbyshire were routed for 72 - their lowest ever T20 total - in 14.1 overs chasing Leicestershire's total of 151 for six.
Craig Kieswetter cracked a quickfire 61 as Somerset made it three wins a row with a nine-wicket destruction of arch-rivals Gloucestershire at Bristol.
The home side could post only 125 all out after losing the toss, Hamish Marshall making 33 and Chris Dent 29. Alfonso Thomas claimed four wickets for 35 runs, reward for some accurate yorkers and variations in pace.
Such a total was never likely to test Somerset's big-hitting batting line-up.
Kieswetter and Chris Jones (53 not out) produced a century opening stand in 13 overs and the outcome was never in doubt as the visitors won with 23 balls to spare.
Varun Chopra and Darren Maddy tormented Worcestershire again by leading Warwickshire to an eight-wicket win at Edgbaston.
The pair followed up their Warwickshire record partnership for any wicket in the competition - 119 at New Road two weeks ago - with one of 107 for the second wicket to keep the Bears in the hunt for a quarter-final place.
Chopra, Warwickshire's acting captain, topped his previous competition-best of 65 made at New Road with an unbeaten 75 and Maddy followed his unbeaten 84 at Worcester with 44 from 35 balls.
Warwickshire's win was their fifth in six games and set up a possible showdown for a quarter-final place with Somerset at Edgbaston on Tuesday.
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