5am: Leftward Shift

Tropical Storm Hanna, 5am Advisory:  Forecast Track

Hanna had another trick for us up her sleeve: She accelerated her forward speed to 20 MPH, still heading northwest, and thus the track has shifted left a bit. We’re now looking at a landfall from anywhere from northern Charleston County to Myrtle Beach again, roughly 2am Saturday (though if Hanna continues to accelerate, this timeframe may also speed up).

Hanna 2am Forecast Models

The model consensus bears out a landfall spread roughly from Beaufort back to the NC/SC border, but interestingly enough, the Wilmington landfall that was fairly certain yesterday is no longer even in the cards, according to this run. The 8am runs should shed more light.

The Shift’s Impacts

5am:  Hanna estimated windfield

We can now expect fairly sustained tropical storm force winds in the afternoon through midnight, including winds over 60 MPH at times with gusts near hurricane force, with the worst of the weather coming when it’s dark. The NWS forecast for today calls for 50-60 MPH sustained winds through the night, especially along the coast; those winds can cause power outages, so now’s the time to make sure you’ve got your batteries in place for your flashlight, because it’s a fairly safe bet you’ll need it. The leftward shift also means inland impacts through South and North Carolina will be increased, with the possibility of sustained tropical storm force winds spreading very close to even Greenville, SC now.


5am Hanna Satellite

Hanna’s still a 65 MPH tropical storm, but it’s pressure has dropped to 989 millibars, suggesting that it has strengthened slightly and could continue to do so. The possibility still exists for it to become a minimal hurricane by landfall, though that’s a matter of semantics when dealing with the differences between a minimal hurricane and a strong tropical storm. Its satellite appearance is still not wonderful, but there is a bit of a flareup of storms on the leftward edge, which is captured well by Melbourne’s radar site.

Hanna as seen by KMLB radar site, Melbourne, FL

Continuing Coverage

Coverage continues throughout the day. Stick close to here and Twitter for updates, including on-air times (which may be fairly soon as conditions begin to deteriorate).


5am: Hanna Still Drifting

Not much on Hanna has changed since the 11PM advisory; it’s still at 80 MPH drifting west at 2. What we’re waiting for is that turn to start, and that’s not expected to happen until tomorrow. The sooner it begins turning, the more northward the track will likely go.

One thing that bothers me from this morning’s advisory is this passage from the NHC discussion:

It is important to note that
Hanna is expected to continue to intensify…or at least remain
steady…until landfall occurs between 84 and 96 hours…rather
than appear to be weakening like some automatic intensity plotting
software may show. In fact…by 84 hours Hanna could be a major

The GFDL model has indicated for the past several days that this could hit minimal Category 3 strength before landfall, and for the first time it appears NHC is supporting this theory. Intensity is a struggle to predict; this deserves further watch as a potential Category 3 strike changes the game dramatically in terms of evacuations and other preparedness steps.

Here’s the full run of model plots from overnight. You’ll see two clusters; one favoring the Savannah track, and one favoring the northerly track into Charleston. GFDL also seems to want to target Myrtle Beach:

All Forecast Models -- Hanna -- 6am

Here’s one that focuses on the more tropical-oriented models; call it the “low-carb” spaghetti plot if you will. Note a bit more spread with these on the orders of hundreds of miles — this is significant, and why the cone of uncertainty is still so wide:

Significant Model Runs -- Hanna -- 09/02/2008 5am

And, for completeness’ sake, the largely unchanged official forecast, which still targets a Category 2 landfall now over Hollywood/Ravenel (but this is still minutia; still a long way to go to determine specifics):

Hanna Projected Path, 5am Advisory 09/02/2008

I’m hoping later today we’ll start to see what a projected wind field may look like over Charleston (and also hoping that maybe this thing will jog out to sea, but that’s not looking too likely at this point). Today is a good day to commence your preparations; my advice is to prepare as if it’s a medium Cat 3 at landfall. While that might not end up being the case, it’s best to over-prepare at this point. If in fact the higher intensity does begin to bear out, you may need to start thinking of evacuation plans depending on where you are.

I’ll be doing a video chat with the 5PM track and 8PM information at about 9:15 tonight. Stay tuned…it’s just now getting interesting.

As Per Whatever

Florence seems to be content

Tropical Storm Florence hasn’t changed much over the last couple days, remaining as a 50 MPH tropical storm as it battles wind shear and other factors inhibiting it. As the discussion states, predicting Florence’s intensity is going to be a mighty tough endeavor, and there’s a lot of uncertainty. Strengthening to a hurricane is still built into the forecast, though.

Here’s the map:


Note that Bermuda may be in big trouble with this current track, as it passes the center just to the left of the island, putting it squarely in the path of the worst part of the storm. Just how bad the worst part of the storm is remains to be seen, but as evidenced by the map they are still expecting a hurricane of varying intensity at the time of Bermuda landfall.

As Per Whatever

So far, it’s just a really gloomy, lousy day.

Well I sure as heck couldn’t wake up again at 5am, and that’s probably a sign I have a twinge of sanity left. It’s a tad soggy out but nothing out of the ordinary has been recorded. I’ve measured about 0.18″ of rain so far from the first outer band — yeah, that was it.

Seems like with every passing update, the further east the track gets pushed. Get a load of the 5am advisory:

5AM forecast track of Ernesto.  Courtesy NOAA

We’re now looking at a landfall just a hair below the border. Charleston is even less likely now to feel those tropical storm conditions. We’ll see if there are any tweaks at 8 and 11 but I must say that we are getting awful close to landfall. However, never ever ever rule out the ability of a tropical system to jog one way or the other — ten miles can make a big difference. Also, it’s worth noting that Ernesto’s a 50 MPH system now, and will probably intensify even further on the final leg of its journey.

See you guys sometime after 8. I may hop out and get milk. Haha.

As Per Whatever

5am: Track holds, Ernesto still 45 mph

A quickie before I hit the shower, as not much changed overnight. See the obligatory track map:

5AM forecast track of Ernesto.  Courtesy NOAA

  • The 5am advisory doesn’t adjust the track much at all, except it bends it a little more due north after landfall. The point of landfall (northern Charleston County/southern Georgetown County) has not changed.
  • Ernesto is starting to interact heavily with the Florida peninsula. It hasn’t lost any intensity at 5am, but we’ll see what happens with the 8am advisory. It needs to start losing strength soon; remember, the stronger it is when it comes off of Florida, the higher of a chance it has to intensify to a Category 1 hurricane before its second landfall in SC.

Watches and warnings haven’t yet changed but that will most certainly change as we go through the day today. Expect a tropical storm warning during the day, probably by 5PM.

I’ll be back at 9, after class, with a look at how the 8am advisory shapes up.

As Per Whatever

Good morning folks…my thoughts on the latest track

We’re getting close to the 8am intermediate advisory (for which I’ll have no comment as I’ll be in class and working at that time), but I wanted to share a few thoughts on the 5am track from the NHC:

5AM forecast track of Ernesto.  Courtesy NOAA

  • The timetable for the center’s arrival has fluctuated, but the timetable for the arrival of the effects has become more clear, and overnight Wednesday is likely when the “fun” will begin, if the speed of the track holds. With this in mind, expect tropical storm or hurricane watches to be posted for our coastline possibly as soon as 11am today.
  • Ernesto will have only about 24 hours over water — these are warm waters, but it will be closer to the coast than previously forecast, and that will mean a limit on how much energy it will gain before it makes landfall.
  • The Hurricane Center seems pretty confident Charleston will see the center of the storm, as this has been forecast pretty consistently over the last 12-24 hours. During the day on Thursday, probably around 2 (yes, it sped up a few hours), I think we can expect some pretty dramatic weather.
  • The Hurricane Center expects top sustained winds of about 65 mph at landfall in Charleston. This could cause scattered power outages, but certainly is an improvement from the 80 mph hurricane that was facing us yesterday.

Now is the time to get ready for the unexpected. With a landfall that is increasingly more likely to coincide with high tide, it’s important for Downtown and other coastal residents to be prepared for flash flooding. This is going to be a rainmaker that won’t go away for a day or two, so expect some massive rainfall amounts.

As Per Whatever

NWS: Metro Charleston could see hurricane-force winds Friday night

The story for the last day or two has been Hurricane/Tropical Storm Ernesto, as the computer models have been taking it over or very close to Charleston sometime during the day on Friday.

The latest forecast track speeds things up by about 12 hours or so and paints a bleaker picture for Charleston. If the track holds — and hurricane forecasts five days out rarely do — Charleston will likely see hurricane force winds as the center of Ernesto passes probably within 20 miles of the coast as it recurves out to sea. This is similar to 2004’s Charley, where Charleston was battered by high winds and heavy rain for several hours as the storm’s center passed to the east.

The Charleston NWS office has released a special weather statement along these lines:

Tropical Storm Ernesto is expected to move northwest across
eastern Cuba today and move towards South Florida on Tuesday.
Based on the latest forecast from the National Hurricane
Center… Ernesto is expected to make landfall across South
Florida Wednesday morning as a Hurricane. Ernesto is then forecast
to move north across much of the Florida East Coast Wednesday and
be positioned off Georgia and South Carolina coasts by Thursday
night as a hurricane.

Based on this track… tropical storm force winds… wind speeds of
39 to 73 mph… and heavy rain could occur over portions of South
Carolina and southeast Georgia… particularly the coastal areas…
Thursday into Friday. This includes the Charleston… Savannah and
Beaufort Metro areas. There is a slight possibility that hurricane
force winds… wind speeds in excess of 74 mph… could also impact
portions of the middle South Carolina coast… including the
Charleston Metro area.

Now’s a good time to think about where to evacuate your cars. Hopefully the parking garages will be open well in advance of an event like this. Unless it grows into the second coming of Katrina, I fully intend on riding it out here, monitoring the storm’s effects using my weather station.

Please also note that future posts on Ernesto will be categorized as such for the historical records down the road.