Here's a press release from the city:
Philadelphia Braces for Impact of Hurricane Irene,
Mayor Nutter Urges Philadelphians to Prepare Now
The City of Philadelphia is closely monitoring the track of Hurricane Irene and its potential impact on Philadelphia.
The National Weather Service forecast has worsened overnight. The official track has moved to the west and Hurricane Irene is expected to track closer to Philadelphia. This potential track means heavier rain and higher winds. If the current forecast holds or the track moves even further west, the combination of rain and wind will make Irene the worst hurricane to hit Philadelphia in at least 50 years.
Rain could start as early as Friday night ahead of the hurricane.
Heavy rains could affect Philadelphia through Sunday.
Heavy winds could affect the city Saturday night into Sunday. High winds may continue after the tropical storm passes.
With the current forecast track, Philadelphia can expect the following:
Rainfall exceeding 7", which would send all streams, creeks, and the Schuylkill River into flood stage. Flash flooding in streets and low lying areas could also be expected. Tidal flooding along the Delaware River is also possible.
Sustained winds of 40-50 mph with gusts to 60 mph or higher. This level of winds could cause downed trees, power outages, and other infrastructure disruption.
To date, August has been the 2nd rainiest month in Philadelphia's history. So rainfall from Irene could cause severe flooding in the city.
Philadelphia has many flood prone areas, including but not limited to:
Cobbs Creek and the marsh lands in the southwest sector of the City;
Other City creeks & streams including Pennypack, Poquessing, Tacony, Frankford, and Wissahickon Creeks;
Main Street Manayunk;
Portions of the Philadelphia Naval Base;
Delaware River which is usually first observed along Delaware Ave & Ben Franklin Bridge;
In the Northeast where Linden Avenue meets the Delaware; and
Kelly and Lincoln Drives.
Flooding may involve numerous hazardous conditions, including moving water, washed-out roads, damage to utility systems, and damage to structures.
It is strongly recommended that Philadelphians living in flood prone areas make alternative arrangements to stay with family or friends whose homes are not prone to flooding for the course of this event and until the flooding threat subsides.
If you are driving and encounter flood waters or standing water, do not attempt to drive your vehicle through the water. Try to find an alternate route or wait until the water recedes.
Before flooding occurs, Deputy Managing Director for Emergency Management encourages residents and local businesses to:
Sign up for ReadyNotifyPA, the region's emergency text and email alert system at www.phila.gov/ready or texting PHILA to 411911 from your cell phone. Future updates on flooding will be sent to the Weather Warnings groups and the River - Schuylkill at Philadelphia groups.
Monitor National Weather Service forecasts at http://weather.gov/phi
Know your area's flood risk. To estimate your flood risk and flood insurance premium, visit www.floodsmart.gov.
Make an itemized list of personal property, including furnishings, clothing, and valuables.
Fill out an Emergency Plan Card containing important emergency information and contacts for you and your family. A template can be found at www.phila.gov/ready.
If you live in a flood-susceptible area, keep materials, such as sandbags, plywood, plastic sheeting, and lumber, on hand to help protect your home.
Consider getting flood insurance. Protection against loss due to floods is not covered under a homeowner's policy. Flood insurance is offered through the National Flood Insurance Program (NFIP).
Listen to local news for critical updates.
If your home is susceptible to basement flooding you should:
If possible, seal any floor drains in your basement, as they are the lowest points of entry of sewer backup.
Do not store anything of value in your basement. If you have time before the next heavy rainfall, relocate your valuables prior to flooding.
To prevent sewer blockages never pour grease, paint or other thick liquids into sinks or drains. Avoid flushing items that are not suitable for sanitary sewer disposal such as paper towels, diaper wipes, contraceptive and feminine products.
Verify with your insurance company if you have flood and sewer backup coverage, especially if your basement is finished. This will usually require a separate rider to your policy.
Never enter a flooded basement – the risk of electrocution is present. Wait for the water to subside.
For information about Flood Insurance or further Flood Preparation Tips, visit the Floods page of the Office of Emergency Management's web site at www.phila.gov/ready or
call 3-1-1.
To learn how to prepare for emergencies and to get a list of emergency supplies, visit www.phila.gov/ready.