$(id da modal).on('show.bs.modal', function(e){ código });

<div style='white-space:nowrap;'>
   <table class='table table-striped'>
      <thead>
         <tr>
            <th>Situação</th>
            <th>Contrato</th>
            <th>Número</th>
            <th>Conclusão Prevista</th>
            <th >Alterar</th>
            <th>Detalhes</th>
         </tr>
     </thead>

     <?php
     $x = 1;
     while ($exibirRegistros = mysqli_fetch_array($consultafull)) {
        $codigo = $exibirRegistros[0];
     ?>

    <tbody>
       <tr>
          <td style='background-color:#F8F8FF'>$situacao</td>
          <td style='background-color:#F0F8FF'>$contrato</td>
          <td style='background-color:#F8F8FF'>$numero</td>
          <td style='background-color:#F0F8FF'>$data às $hora</td>
          <td align='center' style='background-color:#F8F8FF;'>
             <button style='background:transparent;border:none; color: #CD3333;' class='glyphicon glyphicon-edit' data-toggle='modal' data-target='#Alt'>
             </button>
          </td>
          <td style='background-color:#F8F8FF' align='center'>
             <button style='background:transparent;border:none; color:#3A5FCD;' class='glyphicon glyphicon-search' data-toggle='modal' data-target='#Modal'>
             </button>
          </td>
       </tr>
   </tbody>
   <span id="conteudo<?php echo $x; ?>" hidden>
      <?php echo $codigo; ?>
   </span>
   <?php
   }
   ?>
   </table>
</div>

<!-- Modal  -->
<div class="modal fade" id="Alt" role="dialog" data-backdrop="false" style=" background: rgba(0,0,0,0.5);">
<div class="modal-dialog modal-lg">
<div class="modal-content">
<div class="modal-header">
<div class='row'>
<div class='col-sm-5'>
<h4 class="modal-title">Alterar</h4>
</div>
<form method="post" action="func/define.php" enctype="multipart/form-data">
<div class='col-sm-5 text-right' style='float: right'>
<td align='center'><button type='submit' class='btn btn-danger'>Alterar</button>   <form align='center'><button type='button' class='btn btn-primary' data-dismiss='modal'>Sair</button>
</div>
</div>
</div>
<div class="modal-body">
<p></p>
</div>
</div>
</div>
</div>
<!--Fim Modal -->

$('#Alt').on('show.bs.modal', function(e){
   var html = $("span#conteudo"+$(e.relatedTarget).data("conteudo")).html();
   $(".modal-body p", "#Alt").html(html);
});

<td style='background-color:#F8F8FF'>$situacao</td>

<td style='background-color:#F8F8FF'><?php echo $situacao ?></td>

<td style='background-color:#F8F8FF'><?=$situacao?></td>