By Geoff Bansen

PHILADELPHIA (CBS) – Tropical Depression Bill is now well onshore, and is moving through central and northern Texas. Despite never being a serious threat in terms of typical tropical hazards (wind, storm surge), it is now dumping flooding rains on the U.S. mainland. Flood watches are in effect from the Gulf of Mexico, through Texas and Oklahoma, and all the way up as far north as St. Louis.

Many of you may remember Tropical Storm Allison, responsible for drenching southeast Texas back in June of 2001. Allison went on to soak many other cities as well, including Philadelphia, where flooding cost four people their lives. Bill has many similarities to Allison. It made landfall in the first half of June, it contains an immense amount of moisture, and it is forecast to eventually impact the Delaware Valley, all just like Allison.

Latest Forecast:

Some of the worst flooding is actually caused from weaker tropical storms and not hurricanes. While storm surge and wind are always potential threats with tropical systems, more people have died from inland flooding in recent history. Look for this tropical moisture to reach the region late Saturday night into Sunday morning, meaning Father’s Day – and the first day of summer – could be a soggy one.

Forecast to be below average mostly due to a strengthening El Nino pattern, the 2015 Atlantic Hurricane season is already making history. This is the first time that both an ‘A’ and ‘B’ named storm have made landfall in the United States before the end of June.