So I wanted to be bold...

And go with my gut that Hanna wasn't going to be a hurricane...and then the Hurricane Hunters find 75 mph winds...oops. Maybe the winds are finally catching up to that 980 mb pressure. I can admit when I am wrong, and here might be another good case of it. The convection tried to wrap around, started to die (when I was writing my blog) and then has now reintensified near the center again. If the storm keeps itself together through the daylight hours, we could see Hurricane Hanna at landfall. Its a big if though, with all this shear. The models aren't as bullish with Hanna as when she was in the Bahamas. Will have to wait to see if the NHC ups Hanna to a Hurricane at 2pm EST...


And the update is in: Tropical Storm Hanna at 981 mb and winds of 70 mph. So its close, but not there yet per the NHC. Except, looking at the Hurricane Hunter data over the last update, they are finding abundant surface winds of 75 mph, which makes me think its almost a sure bet we have Hurricane Hanna by 5 pm.

Tropical Update

Tropical Storm Hanna

Hanna is looking very ragged right now in satellite imagery. The system has gained considerable convection over the last few hours, but shear and dry air are still battering the storm. The satellite image above (IR because visible wasn't showing much at the moment) indicates the convective burst by the bright red colors. However, notice the sharp transition from red to no clouds on the south side of the system. This is because of southerly shear pushing the cloud tops off to the north and abundant dry air on the southern side that has been entrained into the storm.

Hanna is currently trying to wrap this convection around the center, but it appears the shear might be winning out, pushing the strongest convection towards the north away from the low level center. This does not bode well for Hanna (or, in SC and NC case, bodes very well!) for as long as the shear holds up, the storm is going to have a very difficult time strengthening. Hanna is not doing what it did earlier in the southern Bahamas, where it was able to strengthen to a hurricane even though it was in a high shear environment. Even on radar imagery the system does not look to be organizing its low level center.

Right now the track forecast for Hanna looks fairly certain with a landfall in norther south Carolina. If anything I could see it move slightly to the east of there, but I don't see much of a reason to doubt the great model consensus. My original prediction of a GA/SC border landfall wasn't too far off considering I was thinking it would most likely make landfall on the SC side. However, my strength forecast of a Category 2 hurricane was well off, mainly because the shear did not die down like the models has suggested it would.

Hurricane Ike

Ike is looking a bit worse today, having undergone northeasterly shear for the last 24 hours or so. The shear has bit into the eye of the hurricane and we should see some weakening, kind of like what occurred with Gustav as it moved into the Gulf, over the next 1-2 days. I wouldn't be surprised to see Ike as a Category 1/2 storm in two days time if the shear stays as it is currently. However, after two days the upper-level low will pull northward, removing the shear, and a ridge will build in from the east. This will put Ike back into a favorable upper-level wind pattern, and the storm should begin to restrengthen.

My theory is if Ike is able to redevelop its circular eye, this storm is likely to bomb out on its way to the Bahamas and then Cuba/Florida. If the shear has so degraded the system that 1-2 days will be needed to restrengthen the storm, Ike may make it to the Bahamas before getting its eye structured again. A weaker storm will be more likely to push further south than a strong system, so this could have major implications on storm track. However, considering Ike's presentation at the moment, and the favorable conditions ahead of it, I am leaning towards the stronger end. I wouldn't be shocked to see a nice eye form in 2-3 days as it approaches the Bahamas, allowing the system to charge up off of the warm (relatively un-disturbed from a weakened Hanna) waters.

Right now, with great model consensus, southern Florida looks as the greatest threat location. However, the models have been trending more and more west/south with the system, and Ike could try to go through the Florida Straights towards Key West and then curve up the western coast of Florida...or hit Cuba. A few models still turn Ike up the eastern seaboard into the Carolinas, but its looking less likely. I wouldn't rule it out since five day forecasts can be full of errors (ex: Hanna, Gustav for strength!), but the tracks forecasts this year, by the models and NHC, have been extremely good. The GFDL (except for Fay) has been right on this year in regard to track, and it currently has Ike plowing into Cuba and then moving up the western coast of Florida.

Tropical Storm Josephine

This system can easily be described by the image above. As they say, a 'picture' says a thousand words. (Quickly: Highly sheared, exposed low level circulation. Often described as a 'naked' swirl. A good indication of a weakening, or dissipating, system. Jo is going to need a new burst of convection or its done.)

Update coming...

I will be updating on Hanna and Ike in an hour or so. Until then some quick info:

Hanna is a moderate Tropical Storm moving towards South or North Carolina. The high has built in from the east and is now pulling Hanna northward along the Florida coast. She will likely make landfall sometime Friday night or Saturday (haven't looked at anything really, so my timing could be a bit off).

Ike, last time I checked as a Category 4 hurricane, but shear has done a number on the system and it will likely weaken over the next two days. Ike looks like it could be a monster storm heading towards either Cuba or Florida. Florida is the model consensus location at the moment (specifically, Miami...).

More in depth update coming!

Hanna Update

Tropical Storm Hanna has been moving east-southeast over the last 5 hours, a little different than yesterday. The map below shows the vortex messages (red circled the most recent) produced by the Hurricane Hunters. They have not been able to find any flight level winds above 70 mph, so the storm has stayed a Tropical Storm, with reduced wind speeds of 65 mph. I have no problem with that forecast.



Also since last time, the 18Z models have come out, and the trend has been to go back eastward again! Basically, the models are not really sure what Hanna will do and we won't know until she starts moving north. I am still sticking with my GA/SC border landfall location, mainly because I put forth that forecast yesterday. However, my confidence is low at this point. Definitely a wait and see situation.

Ike and Josephine have both intensified over the day, up to 65 and 50 mph respectively. Ike will likely be a hurricane tomorrow, and if shear doesn't get too strong in 48-72 hours, could be a category 2 storm. The SHIPS model is forecasting stronger shear during that time, so Ike could weaken back to a Tropical Storm, but conditions will once again become more favorable in 5 days. Ike looks like it could be a major threat for some land mass in the future. I question the shear forecast, but we shall see. Currently Ike is under an upper-level anti-cyclone which has helped the system strengthen.

Tropical Storm Hanna

Hanna has weakened slightly this morning and is currently a 70 mph hurricane. The Hurricane Hunters are currently in the system and have found a minimum pressure of 985 mb and flight level winds near 70 mph. The instrument that measures surface winds has been recording near 100 mph winds over the last 20 minutes...but the upper-level winds do not support this. So, I am thinking their instrument must be recording bad data, and if I was at the NHC right now I would keep Hanna a Tropical Storm.

The storm has continued its drift to the southwest today as strong shear continues to batter the system from the northwest. The shear has been produced by Gustav, and should decrease in the next 24 hours-48 hours. Until then, Hanna is going to have a very difficult time strengthening. When the shear lightens up, the storm may then go through a strengthening phase as it is pushed to the northwest as a ridge builds in from the east. The models have been trending further and further west/south with each model run, and right now the consensus is in southern GA/northern FL. Generally the models bring Hanna close to Florida and then drive it right up the coast, just out to sea, towards the GA/FL border. With Hanna still not showing any desire to move north, it is still very difficult to pinpoint a landfall location.

I still think Hanna could become a Category 2 hurricane once the shear dies down. The storm has been very resilient and should be able to strengthen once the atmospheric conditions become a bit more conducive for strengthening.

A little note on Ike: The storm has strengthened some and is still moving west. Atmospheric conditions and models still support the same conditions as yesterday, so the track should keep west-northwest and then west to west-southwest over the next 5-7 days. Any forecasting of a storm's path beyond seven days is foolish, but a US landfall is definitely possible. Josephine has also developed in the far eastern Atlantic, the 10th named system of the season.

Hurricane Hanna Forecast

Currently Hanna is located in a high shear environment created by the outflow from Hurricane Gustav. Gustav has made landfall and should weaken substantially now, and is already down to 80 mph winds from 115 mph this morning. As this continues, the shear caused by Gustav will weaken, which the models also confirm. However, this shear will not weaken substantially for another 36 hours. Luckily for Hanna (or un-luckily for the southeast US), she will stay in the southern Bahamas for this time period as Gustav's strongest shear moves north. Thus, considering she has survived the near 20 knots of shear over her now, she should be able to hold her strength or strengthen over the next 36 hours.

After 36 hours, things begin to change substantially. Gustav's shear will be minimal to moderate over Hanna, closer to the 5-15 knot range, allowing her to develop further. Upper-level divergence should be established over the system and the storm will still be over warm sea surface temperatures. Thus, I wouldn't be surprised (if she can survive the shear for the next 36 hours and keep her strength) to see Hanna reach Category 2 strength.

At 36-48 hours, a building ridge should begin to slide from the central Atlantic towards Hanna. With clockwise rotation around a high, this should begin to push Hanna towards the north-northwest. The GFS and European produce a stronger ridge than the CMC model. Thus, they push Hanna a bit further to the west into the GA/SC border region, while the CMC tracks the storm into NC. Right now, considering the CMC completely bombs out the system (which is unrealistic), which is likely a reason the ridge isn't depicted as strong, I am thinking on leaning on the European and GFS models. This also happens to be the area of greatest clustering of the rest of the models as well. Thus, right now I predict a GA/SC border landfall as a Category 2 storm.

As the system moves north, shear should remain low until 24 hours before landfall. At that time the models want to increase shear slightly over the North Carolina area. Considering Hanna's ability to keep her strength (and strengthen!), and Gustav's ability to stay a Category 3 all the way to landfall in a high shear environment, I think she should stay together and make landfall as a Category 2 storm. The landfall location will be very important in regard to Savannah, GA. If it lands on the GA/SC border the city will be spared from the surge. If it makes landfall to the south, the city will be inundated. Savannah is a city that can easily be washed away because of its close proximity to the water. Add on a local mentality that storms always miss their area, and a disaster could be on our hands. Hopefully Hanna turns more than expected, and maybe even goes out to sea...but I don't see that right now.