Mobile (3)
Auburn (2)

Array
(
[0] => Array
    (
        [0] => Array
            (
                [city] => Mobile
                [numLocations] => 3
            )

        [1] => Array
            (
                [city] => Auburn
                [numLocations] => 2
            )

    )

)

while($row = mysqli_fetch_assoc($result)){
    $state = $row['state'];
    $stateAbv = $row['stateAbv'];
    $city = $row['city'];
    $numSLocations = $values['cnt'];

    if (!isset($rows[$row['state']])){
        $rows[$row['state']] = array();
    }

    $rows[$row['state']][] = ['city' => $city, 'numLocations' => $numStores];
}

foreach($rows as $state => $cities){
   echo array_column($cities, 'numLocations'));
}

while($row = mysqli_fetch_assoc($result)){
    if (!isset($rows[$row['state']])) $rows[$row['state']] = 0; //initialize with 0

    $rows[$row['state']] += $row['cnt']; //increment the num Stores
}

['Mobile' => 3, 'Auburn' => 2]

$numSLocations = $values['cnt'];

foreach($rows as $state => $num){
   echo "$state ($num)nn";
}

Mobile (3)

Auburn (2)

print_r(array_column($array[0], 'numLocations', 'city'));

foreach($rows as $state => $cities){
   echo array_column($cities, 'numLocations')); //returns an array
}

[0 => 3,1 => 2]

array_column($array[0], 'numLocations')