Tag Archives: weakening

Wait and see continues…

The wait and see game continues with Hanna at the 11PM advisory. The storm’s back to being virtually stationary, drifting eastward every now and again, but movement is not very pronounced. NHC continues to list Hanna’s intensity at 65 MPH; however, this could be generous. Check out Hanna’s satellite appearance.

Tropical Storm Hanna at 11PM 09/02:  Satellite

Here’s what the Hurricane Center discussion has to say:

THE CLOUD
PATTERN HAS CONTINUED TO DEGRADE…AND IT IS POSSIBLE THAT HANNA
HAS WEAKENED EVEN MORE. HOWEVER…WE WILL KEEP THE INITIAL
INTENSITY AT 55 KT SINCE ANOTHER AIRCRAFT IS SCHEDULED TO
INVESTIGATE THE STORM AROUND 0600 UTC.

This apparent weakening is undoubtedly good news and appears to have gone on a little longer than previously expected. (We’ll take what we can get here.)

Back on Track?

Tropical Storm Hanna at 11PM 09/02: Forecast Path w/ Cone

The forecast path has not changed much during the day. The angle of approach has been adjusted somewhat, but NHC has been very careful not to alter the path until Hanna finally starts the northwestward turn. Only after the turn begins will landfall points even begin to get a smidgen clearer. One thing to notice is that the updated track is a bit slower (for the moment, at least), pegging landfall now for later on Friday night versus in the afternoon. This is definitely something that could fluctuate depending on when Hanna starts moving and how fast it’s accelerated.

Tropical Storm Hanna at 11PM 09/02: Forecast Models

The computer models want to tell a different tale, though. After a brief jog to the west, they’ve since started trending rightward again, likely as a result of Hanna’s eastward movement during the evening. The models bear out a variety of scenarios; some, like HWRF, favor the southerly track, while GFDL, which has consistently veered more to the north, currently likes Isle of Palms. There’s significant agreement, though, for a landfall near Myrtle Beach. Some consensus is also building for an alternate clipping of the Outer Banks, though I’m not sure if that would come to pass as the HWRF and GFDL models have been exceptionally reliable. It’ll be interesting what will come out of the models when the recon data is taken into account. (NHC lists the next recon plane as going in at roughly 2 AM EDT.)

Impacts

It’s still too early to tell — besides pretty decent amounts of rain and some elevated winds, probably to tropical storm force at times — what impacts Hanna will have on the area as the landfall location is still anybody’s guess. Using the current landfall location, though, I’m able to use an experimental wind field forecast product to give a general idea of what windspeeds to expect.

Tropical Storm Hanna at 11PM 09/02: Estimated Wind Field

The gray field is tropical storm force winds; the purple field are stronger tropical storm force winds up to 73 MPH. No hurricane force winds are depicted yet; if in fact Hanna makes landfall as a Category 1, expect those hurricane force winds (74 MPH or greater) to be concentrated about 20-25 miles to the northeast of the center. Intensity, storm size, etc. are still very touch and go at this point, so don’t read too terribly much into this; however, the estimation does show that a great deal of the state, including points as far west as Columbia and Augusta, could see tropical storm force winds for a time. Again, this should be interpreted as a general idea, and it’s quite possible a lot could change.

Closures, etc.

No word on any closures yet. The Charleston County School District has established a Hanna information page which will update as schedule decisions are made. Dorchester District 2 posted an inclement weather policy, but no closing information as of yet. I’ve not seen anything similar for Berkeley or Dorchester 4. Keep tuned to the local media outlets for up-to-the-minute closures and cancellations information.

More in the morning when the recon data is in; hoping that my getting some sleep will persuade Hanna to make a decision one way or the other so we can start trying to figure her out with some effectiveness. :)

Tonight’s Hanna briefing

Tonight’s briefing covered the latest on a ragged-looking Hanna, which has been erratic most of the day. I focused a lot on the models and a lot of the variation throughout today; things are still quite uncertain. I’m holding out hope that the 11PM advisory will start to shed some light but that might have to wait for a few more hours.

Hanna’s definitely not moving much, and its satellite presentation is very poor. It looks like it’ll be weakened even further with the next advisory…only time will tell. I’ll have more after 11…