Line a 9x5-inch loaf pan with plastic wrap or parchment paper, leaving about 3-4 inches of overhang on all sides. Place the prepared loaf pan in the freezer to chill. 

For the raspberry sauce: Add the raspberries, lemon juice, water and granulated sugar to a small saucepan. Cook over medium heat, stirring frequently, for 5-10 minutes or until the raspberries burst and the sauce has thickened. Strain the sauce through a fine mesh strainer. Set aside to cool completely. 

In a large glass bowl over a pot of simmering water, add the egg yolks, granulated sugar, lemon juice, lemon zest and salt. Whisk constantly until the egg yolk mixture is thick and pale and has reached the temperature of 165F. 

Remove the egg yolk mixture from the heat. Whisk until the mixture has cooled down. Stir in the vanilla extract. Set aside. 

In a large mixing bowl, add the heavy cream. Beat until medium-soft peaks form, about 3-4 minutes. 

Gently fold the heavy cream into the egg yolk mixture. 

Spread half of the semifreddo mixture into the prepared loaf pan. Spoon ⅓ of the berry mixture into the semifreddo and swirl with a knife. Top with remaining semifreddo mixture. Swirl another ⅓ of berry sauce into the semifreddo with a knife. Store the remaining ⅓ berry mixture in the refrigerator in an airtight container for serving. Cover the semifreddo with the overhanging plastic wrap. Freeze for at least 6 hours until firm. 

When ready to serve, remove the semifreddo from the pan and invert it onto a serving platter. Top with remaining berry sauce and fresh berries for garnish. Slice and serve.