Feeling the heat

Wish I could remember what these large yellow flowers are called : ). The Calgary Zoo has a whole flowerbed full of these beautiful blooms, each flower seeming to be at a different angle. I was going to say that this is rather how I feel today, after a long, hot, afternoon walk - but then I remembered you, Rebecca, dealing with even hotter temperatures! Had to smile when I saw your comment below, LOL. Thanks for the ID, Linda - Rudbeckia!