Dave - I've been watching that site and the Patapsco's water temps like a hawk all winter. The monitoring site is located next to the fireboats, not too far from the taxi pier at Fort McHenry. And I agree, sometimes water temps there just don't always respond like I would expect based on air temps. Certainly the Middle Branch at HH has gotta be near about frozen over by now... if not then it should be shortly. BTW, the temp sensor at this site is located 5' below low tide.