Avira, thanks for clarifying the water non resistance! You just can’t trust internets any more!
Is it ok to keep the black hat in shul together with the talles & tefillin during rainy season? Or is it a financial risk? Some might learn not to worry about a stolen hat from a kal vahomer with the tefillin, but it is not so – as stealing tefilin is a bigger aveira, no “frum bochur” will dare, and also harder to resell! (I am channeling Rav Yehuda – a need for a convoy for Sotah v Niddah).