Edit in JSFiddle

th {
    background-color:#046380;
    color:#EFECCA;
    padding:3px 10px;
    text-align:center;    
}
tr:nth-child(odd) {
    background-color:#F8EAC5;
}
tr:nth-child(even) {
    background-color:#D8D0AC;
}

td{
    text-align:center;
}
<table>
<thead>
<tr>
    <th rowspan="3"><strong>TARİH</strong></th>
    <th colspan="7"><strong>TAHMİN EDİLEN</strong></th>
    <th id="ctl00_mpBody_gcmThA" colspan="4" tiptitle="Bu bölüm, son 30 yıl içinde, bu tarihlerde gerçekleşen en düşük ve en yüksek sıcaklık değerini göstermektedir."><strong>GEÇMİŞTE GERÇEKLEŞEN</strong></th>
</tr>
<tr>
    <th colspan="2">Sıcaklık (°C)</th>
    <th rowspan="2">Hadise</th>
    <th colspan="2">Nem (%)</th>
    <th colspan="2">Rüzgar (km/sa)</th>
    <th colspan="2">Uç Sıcaklık (°C)</th>
    <th colspan="2">Ortalama Sıcaklık (°C)</th>
</tr>
<tr>
    <th>En Düşük</th>
    <th>En Yüksek</th>
    <th>En Düşük</th>
    <th>En Yüksek</th>
    <th>Yön</th>
    <th>Hız</th>
    <th>En Düşük</th>
    <th>En Yüksek</th>
    <th>En Düşük</th>
    <th>En Yüksek</th>
</tr>
</thead>
<tbody>
<tr>
    <th>6 Eylül Salı</th>
    <td>20</td>
    <td>29</td>
    <td></td>
    <td>47</td>
    <td>88</td>
    <td></td>
    <td>23</td>
    <td>11.8</td>
    <td>33.4</td>
    <td>16.8</td>
    <td>25.6</td>
</tr>
<tr>
    <th>7 Eylül Çarşamba</th>
    <td>20</td>
    <td>29</td>
    <td></td>
    <td>48</td>
    <td>88</td>
    <td></td>
    <td>26</td>
    <td>12</td>
    <td>30.4</td>
    <td>16.2</td>
    <td>24.7</td>
</tr>
<tr>
    <th>8 Eylül Perşembe</th>
    <td>19</td>
    <td>28</td>
    <td></td>
    <td>48</td>
    <td>83</td>
    <td></td>
    <td>26</td>
    <td>12.4</td>
    <td>30</td>
    <td>15.9</td>
    <td>24.6</td>
</tr>
<tr>
    <th>9 Eylül Cuma</th>
    <td>20</td>
    <td>26</td>
    <td></td>
    <td>51</td>
    <td>91</td>
    <td></td>
    <td>12</td>
    <td>10.6</td>
    <td>29</td>
    <td>15.8</td>
    <td>24.9</td>
</tr>
<tr>
    <th>10 Eylül Cumartesi</th>
    <td>19</td>
    <td>25</td>
    <td></td>
    <td>56</td>
    <td>92</td>
    <td></td>
    <td>23</td>
    <td>11.7</td>
    <td>30.8</td>
    <td>16.3</td>
    <td>25.2</td>
</tr>
</tbody>
</table>

<p>Kaynak: <a href="http://www.dmi.gov.tr/tahmin/il-ve-ilceler.aspx?m=istanbul">http://www.dmi.gov.tr/tahmin/il-ve-ilceler.aspx?m=istanbul</a></p>