As Abq Jew wrote in Consoling the Father:
It is the custom in most synagogues to announce the month of Av as "Menachem Av" - literally, "Consoling The Father."This past week has been full of terrible events, truly fitting for the Three Weeks between Shiva Asar b'Tammuz and Tisha b'Av; Bein HaMetzarim (Between the Straits).
The Talmud says, "When the month of Av begins, we reduce our joy." During the Nine Days we observe a greater level of mourning than during the Three Weeks. We don't eat meat or drink wine (except for Shabbat). We don't wear new clothes that require the Sh’he'cheyanu blessing - we are not happy to "reach this season." We don't play or listen to music.
But the Talmud also states that all who mourn the destruction of Jerusalem will merit to rejoice in its rebuilding. The Sages also teach that the Jewish Messiah was born on Tisha b'Av. It is that promise of redemption which makes this period one of hope and anticipation.
Starting with the murder of Andrew Pochter by a mob in Egypt; then the death of Annais Rittenberg, hit by a falling tree at Camp Tawonga in California.
And the crash of Asiana Flight 214 in San Francisco. And the deaths of 19 Granite Mountain Hotshots at Yarnell Hill (see Young Men and Fire for historical reference).
And the three URJ campers injured by lightning in Indiana. And the deadly runaway train explosion in Quebec.
May the Holy One, Blessed Be He, give us comfort during these Nine Days that lead up to the fast of Tisha b'Av. And may the Holy One, Blessed Be He, find comfort, too.