Do Not Underestimate Irene

As a meteorologist I always walk a fine line between warning the public and/or my clients, and preventing a hype factor to a major weather event.  In the case of hurricane Irene, I have been walking this fine line in the forecast for days at NY NJ PA Weather.

One factor is very interesting and perhaps forboding of the future of Irene this afternoon and evening.  Irene has grown in tramendous size the past 24 hours while the pressure feel from 950 MB yesterday afternoon to a low of 942 MB at 11 PM last night, which has leveled off at 946 MB since 5 AM.  These pressure drops usually correspond to surface winds of 120 MB to 135 MB.  However, Irene's wind field has expanded to a tramendous size, which I believe is leading to a lower sustained wind speed over the past 12 hours.  

My concern going forward for this afternoon and evening is that Irene's wind field will stabilize and the wind speeds will start to increase in relation to the pressure values meassured in Irene going forward.  This of course could lead to Irene becoming a strong category 2 or even a category 3 hurricane before land fall over eastern North Carolina.  So even though Irene is weaker now, does not mean Irene can not strengthen and, significantly so, later.

The impacts of Irene are not something to take lightly.  For a comparison, winter storms that slam the New Jersey coast line usually have sustained winds of 25 to at most 50 mph sustained winds with higher gusts.  Those winds would correlate to a weakening tropical storm.  The winds expected for Hurricane Irene from early Sunday morning through the evening hours will range from 75 to 100 mph with higher gusts.  Even for inland locations, sustained winds will still range from 50 to 85 mph through the duration of the hurricane.  I think you can see what I'm point out, even a weakening hurricane is going to be far worse in wind impacts than the strongest winter storms that have impacted New Jersey the past two years.

In addition to the strong winds, there is the matter of rain rainfall.  With rainfall amounts, which has been documented throughout this blog, averaging 200% to 800% above normal for most locations and near normal along the immediate coast this month, flash flooding will be very likely.  Rainfall amounts throughout New Jersey will range from 6 to 12 inches, that's a half a foot to a foot of rain.  This type of rainfall will lead to flash flooding of rivers, streams, and urban locations.  Further the combination of the wet soil with the strong winds will lead to trees and other objects to be up rooted very easily.  

Finally, but certainly not least, is the threat for coastal flooding.  Depending on your location and orientation of your coastal locations with the winds, a storm surge of 2 feet to as much as 10 feet will be possible along the coast, especially at high tides.  Remember, Irene is hitting durring a new moon cycle, which already has enhanced high and low tide cycles.  

Irene is a dangerous storm and one I would strongly suggest preparing for.  Please do not drive in this storm and if you are asked to evacuate, do so.