Andrea Is StrongerJune 6th, 2013 at 8:46 am by Jeremy Wheeler under Weather
We’ve been following the latest on tropical storm Andrea, and it has definitely strengthened in the last 6 hours. In fact when you look at the satellite and radar, it looks like it may be briefly trying to become a hurricane.
Now there is some dry air just to the west of the storm. However, look at how the storms (orange/red areas) are wrapping into the center of circulation. This is a clear sign of strengthening as the upper level winds (shear) aren’t strong enough to blow the storms away from the center. In fact the structure is looking so good, that I wouldn’t be surprised if Andrea briefly becomes a hurricane for one update. Keep in mind though that the water temperatures are cooler along the west coast of Florida. Also, the dry air may be trying to wrap into that center on the southern end. So I suspect that the storm would resume weakening after several hours even if it does drop its pressure. The latest info from the National Hurricane Center has Andrea located about 160 miles west of Tampa, FL. It is moving north/northeast at 13mph. The sustained winds were near 60mph, and the pressure had dropped to 997mb. Heavy rain was pouring over a huge portion of Florida. They can expect 3-6″ there. This storm is forecast to make landfall over Florida later today. Then it is expected to move northeast over land and along the coast.
The latest computer models do generally agree on the forecast track, and now the GFS and European models agree on the speed. The NAM doesn’t look like it’s capturing the strength of the storm very well. It is doing a good job with the rain though. It has the storm moving northeast, weakening, and then passing through the region as a very broad area of low pressure. It is a bit slower than the other models, but I don’t like its solutions. I also don’t trust it much with tropical systems. Both the GFS and European models take the storm inland sometime this evening over the Big Bend of Florida. Then they put it over South Carolina by Friday morning. They quickly push it into our region late Friday into Friday night. It does look like it weakens at that point. Hopefully to a depression or remnant low. Looks like Andrea will shoot away from us after that. Here is our computer model (Future Trak) on Friday at 10pm.
It is just a little slower than the other models. The latest track from the National Hurricane Center is a blend of the GFS and European models.
Here are some of the impacts that we can expect from the storm. Some showers will start up late today into tonight way ahead of the storm. A few showers may be around tomorrow morning, but the bulk of the rain and heavy downpours are expected Friday afternoon and evening. That is when we could see 1-3″ of rain and some cities even more. I think our model is underestimating things a bit, but here is its latest forecast:
I suspect that it will increase the rain totals as the storm gets closer. Due to the speed of this storm and the eventual weakening, I do not anticipate any tidal flooding. We may see some localized flooding from the heavy rain, but the recent dry ground should soak up a lot of what initially falls. Ponding on roadways and some flooded back yards will be a good bet. Winds are expected to pick up in that same time-frame. Winds will be southeast at 15-25mph with some gusts up to 35-40mph near the water. This typically doesn’t do much damage. There may be some scattered power outages, but I don’t think that will be a huge issue.
Finally, we could see some isolated tornadoes. There is already so much rotation in the atmosphere when tropical storms systems move through. Some of that rotation is concentrated in a thunderstorm and therefore a quick spin-up can occur. These are usually very quick/weak tornadoes that don’t do much damage. Not like the monsters in Tornado Alley. Still any possible warnings need to be treated with respect.
Things are coming together a bit on this with the exception of the strong look it has on radar. There will be an update out later this morning. We’ll get another blog out later today. Tropical storm warnings are in effect for our region. That means that some of the gusts may be up to 40mph, and so the warning is basically a precaution. Remember a tropical storm has winds of 39mph up to 73mph.
Meteorologist: Jeremy Wheeler