Flooding fear factors: Tropical rain & falling leaves
Wed, 29 Sep 2010 14:08:51 GMT —
On Tuesday, I started alerting everyone about the potential for localized flooding due to rain on Thursday and Thursday night. That threat continues with the National Weather Service now issuing flood watches for our entire area for Thursday and Thursday night. A flood watch means there is the potential for flooding of streams, creeks, poor drainage urban and low-lying areas. There is no imminent danger from flooding, yet. However, heavy rain is likely late tonight and into Thursday and Thursday night. Upwards of 2 to 3 inches of widespread rain remains a distinct possibility. Some of our computer models indicate upwards of 4 inches of rain or more either in central New York or in eastern NY. This type of rainfall in a 24 hour period would cause rapid river, stream and creek rises and potential flooding of these areas. In addition, with leaves now falling off of trees, local storm drains may become clogged. I am particularly concerned by this extra factor as normal rain runoff on streets may become disrupted for a time. If certain storm drains become clogged, localized flooding may occur anywhere within the viewing area. In addition, if your basement normally gets wet or flooded during heavy rain events, you should prepare for potential water issues Thursday and into Thursday night. You should stay tuned on-air and online to the latest weather updates from the CNYcentral weather team. The exact track of the heaviest rainfall may occur within our local viewing area, or pehaps just to our east. For now, the flood watch continues. If and when areal flood warnings or river flood warnings are issues, then imminent danger from flooding would be more likely. On a side note, wet leaves in general are very slippery. Even if flooding does not occur in your local area, you should be on the alert for extra slippery conditions due to wet fallen leaves.
There is a great resource of flooding terminology that is available to you that you should read over. I amended a flood safety awareness week story that is on our website right now. Click here for more details on flood safety. It explains flood terminology and gives you links regarding flooding information. In addition, there is another web story that describes the Turn Around Don TMt Drown campaign to warn people of the hazards of walking or driving a vehicle through flood waters. If flooding does occur, please do not drive or walk through flooded streets. That article describes why you should avoid this.
In Tuesday TMs web story, I also discussed how flooding can be caused by a combination of regular weather systems and tropical systems. It is an interesting read to compare previous events. While there is no hurricane to be worried about, there is a long plume of tropical rain that extends from Virginia all the way down to Florida, Cuba, and the western Caribbean Sea. In addition, tropical storm Nicole has formed. While Nicole is expected to remain rather weak and transition into a non-tropical low over the next 36 hours, there is little doubt that a heavy dose of rain will occur from the Carolinas to Virginia, Pennsylvania and into upstate New York. This tropical moisture pump in concert with strong jet stream energy in Canada, should create a large amount of rainfall in our area.
While the exact amount of rain may still change, I am concerned about a widespread 2 to 3 inch rainfall with local amounts potentially exceeding 4 of rain locally within a 24 hour time period. This amount of rainfall will likely set records for the date (September 30th), but may also set the maximum rainfall that occurred during any day of the month. The rainfall record for Syracuse on September 30th is 1.53 set back in 1924. The highest amount of rainfall for any day of the month of September is 2.59 on September 24th, 2001. Both of these records may be broken on Thursday.
For more on your weather forecast, click on Weather and then the Live Triple Doppler Radar tab on our weather page. Make sure you refresh the Doppler radar to see the very latest information, as well. Furthermore, we have our new Interactive Doppler Radar on our website. You can zoom down to street level with Interactive Doppler Radar. You are in total control of where the radar can zoom in. Give it a try. In addition, you may tune to NBC Weather Plus on Time Warner Cable digital channel 133 or over the air 3.3 to get the very latest weather updates locally and nationally. Plus, click on Severe Weather Tab to see detailed county watches, warnings, and advisory information. In addition, you can follow along with me on Twitter by either clicking on the follow button on the Twitter section of our weather page www.cnycentral.com/weather or by visiting www.twitter.com/PeteWeatherBeat.