How to re-order user profile form?
The weight you set here would be overridden by the weight values you set via Mange Fields.

However...

You can get around this by changing the weight in pre_render.

E.g. 

function mymod_form_user_profile_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  $form['#pre_render'][] = 'mymod_form_alter_weight';
}

function mymod_form_alter_weight($elements) {
  $elements['account']['#weight'] = 100;

  return $elements;
}