By:
Dr. Jeff Masters,
6:06 AM GMT on August 04, 2008
Well, today was the day one of the co-founders of Weather Underground, Chris Schwerzler, decided to get married. While I highly complement him on his choice of brides, and his choice of wedding days, weather-wise--the weather here in Sonoma California was beautifully clear and 75 degrees--his choice of wedding days was less advantageous weather-wise as far as the tropics are concerned. So, I'm taking a break from the reception to take a look at Edouard.
Figure 1. Latest satellite image of Edouard.
Tropical Storm Edouard has not changed much in appearance over the past 12 hours, as seen on
infrared satellite loops. The heavy thunderstorm activity is limited to the south side of the storm, thanks to about 10 knots of wind shear from upper-level winds blowing from the north. Edouard is over ocean waters of about 29°C, which extend to a moderate depth. The Tropical Cyclone Heat Potential, a measure of the total energy available for rapid intensification, is about 40 kJ/cm^2, which is less than the value of 80 typically associated with rapid intensification. These conditions are very similar to those Dolly had, when it intensified into a borderline Category 1/2 hurricane. A new hurricane hunter plane entered the storm at about 2am EDT, and so far has measured top winds of 36 knots (42 mph) at the surface with its SFMR instrument.
The forecastThe shear is forecast to decrease to near zero by Monday night, and sea surface temperatures will increase by about 0.5°C. The depth of the warm waters get shallower, with the Tropical Cyclone Heat Potential decreasing to about 20 kJ/cm^2 Monday night. Taken together, these factors should allow Edouard to intensify, although it may take 24 hours or so for the storm to organize an eyewall, as occurred with Dolly. The latest 00Z (8pm EDT) GFDL and SHIPS intensity models both bring Edouard to a borderline tropical storm/Category 1 hurricane by landfall, with the strongest winds occurring near the Texas/Louisiana border. The 00Z HWRF model, though, predicts that Edouard will not get its act together at all, and will be a tropical depression at landfall. The latest GFS model is also not very enthusiastic about Edouard.
My best guess is that Edouard will be a tropical storm with 60-70 mph winds when it comes ashore Tuesday morning. It would be a big surprise if the storm made it to Category 2 strength, since it has a limited time before it comes ashore, and is so poorly organized at present. Heavy rain is the main damage threat from Edouard.
I'll have another blog on Edouard Monday afternoon, and Bryan Woods may also chip in Monday morning.
Jeff Masters