Tag Archives: hurricane season 2008

The final word on Hanna; Ike approaches

Full Path of Hanna, From Genesis to End

After Tropical Storm Hanna gave us some much-needed rain Friday, it turned northeast and hit hyperspeed and has made conditions quite interesting going up the Eastern seaboard, dumping a lot of rain and causing some brief flooding issues from North Carolina up into New Hampshire. It’s lost tropical characteristics now, and the Hurricane Center has issued the final advisory for Hanna, which will go down as a reasonably bizarre, devil of a storm to try to predict.

Despite rumors to the contrary, Hanna actually did have some winds. Francis Shepherd had some videos of some of Hanna’s wind and rain from Deltaville, VA on Saturday morning. While the winds didn’t seem too exceptionally strong in those videos, that’s certainly more than I saw from my humble abode in West Ashley.

Ike Satellite Photo

Hurricane Ike lashed a Hanna-ravaged Turks and Caicos Islands and is going to give the Bahamas quite a ride today before it slams into Cuba, likely maintaining Category 4 strength throughout. Evacuations have been underway in the Florida Keys for the last day or two; first, tourists were asked to leave, and now residents are being evacuated as the Keys are under a hurricane watch. They likely won’t see the brunt of Ike’s fury, but even Category 2 winds can cause severe problems on the Keys.

From there, it’s anybody’s guess where Ike will end up. Here’s the path, which could point it anywhere from south of Texas to just to the west of Pensacola.

Hurricane Ike:  Projected Path, 11am 09/07

The forecast has Ike taking a beating from Cuba, but eventually getting it back together in the Gulf and becoming a Category 3 again. Ike’s got folks along the Gulf Coast worried, and rightfully so; this could be a force to be reckoned with through this week. A lot of the folks I followed for Gustav are watching Ike extremely closely, and making preparations now just in case. While it shouldn’t affect us in the Carolinas, thankfully, we’ll be watching the Gulf Coast closely, hoping folks there get out of harm’s way.

11PM advisory: Lifting northward

Hanna’s starting to lift northward of Charleston. The 11PM fix put it roughly about 60 miles east-southeast of Charleston, and I’m willing to bet it’s pulled even or even slightly north of Charleston now, based on some of the radar I’ve been looking at. The advisory also says that it’s moving north at 20; however, I’m seeing strong indications that the turn to the northeast has begun and is now moving in that direction. Landfall is expected just north of Myrtle Beach within the next few hours.

The advisory canceled the tropical storm warning south of Edisto; I could see this being whittled back even further as time goes on. The Hurricane Watch for our area was also discontinued. There’s a chance Hanna could still become a hurricane — it’s been trying to form an eyewall for the past couple hours, and the pressure is as low as you’ll ever see for a tropical storm — but shear is and dry air are giving it one hell of a fight.

Hanna’s dropped plenty of beneficial rain on the Charleston area. The usual spate of flooding has happened; but this happens whenever it rains normally, much less when a tropical system swings through.

I’ll be interested to hear what comes of the postmortem from Hanna. This has been one heck of a storm for many reasons, whether it be its odd track deviations or its odd strengthening habits. It’s been a great learning experience, as well.

I probably won’t be awake for landfall. Here’s hoping that folks in Myrtle Beach and throughout North Carolina come through alright; I suspect things will be okay, though. This storm’s moving incredibly quickly, so widespread flooding won’t be a major issue, and the winds probably won’t get past Category 1, much less tropical storm force.

For now, this will sign off the advisory-by-advisory posting for the Charleston area for Hanna. I’ve made this official by cracking a beer.

I’ll have a recap of Hanna sometime tomorrow or Sunday; right now, I need rest before coverage ramps up for Ike, which is a damn dangerous, scary, and beautiful storm.

Hanna jogged left

Hanna’s made a very sharp jog to the left which has complicated a lot of things in the forecast. It’s looking more and more that unless the northeast turn happens in the next couple hours from now, landfall will indeed be in northern Charleston County near Awendaw and Bulls Bay. The Hurricane Hunters are in the storm as I type this and there is some really interesting data coming back — it looks like the pressure at the center fix is 978 mb. The fix puts the center about 85 miles to the southeast of Charleston. It’s hauling butt, too, and I’m sure that fix is outdated by this writing.

As I write this, a squall associated with the inner core of the storm — which is rapidly regenerating — is coming ashore. The worst may be yet to come…keep tabs in the Charleston Weather broadcast and chat room. Next advisory at 11…

Hanna: A non-event so far

Obligatory

Computer models and forecast tracks aside, so far, Hanna’s been quite a beneficial rainmaker for Charleston, and not much else. I’ve seen some fairly heavy showers come through at times, but the winds have definitely been nothing like what was expected. The winds were actually stronger earlier today; in the last few hours, while the rain has definitely gotten harder and more steady, the wind has just not been where it’s been expected. This could change as the center passes closer at 8:00 (the buoy reports do indicate stronger winds — but nowhere near 70 MPH, either), but by every measure, we should have been in tropical storm force winds by now. This simply has not happened. We’ve gotten much-needed rain — we’re down 8″ here in Charleston — and none of the problems that usually come with it (save for downtown flooding, but that’s not avoidable).

I do suspect things will kick up a bit as the center approaches — judging from the buoy reports I’ve been looking at, we could see 25-35 MPH sustained winds at times — but I think predictions of hurricane conditions in Charleston are far overblown at this point. Everything I’ve seen just does not sustain that.

My faithful Charleston weather watchers and I will continue to keep an eye out in the Charleston Weather broadcast, but it looks like we need to pay much closer attention to Ike and let this glorified late summer nor’easter do its thing. :)

2PM: Hanna headed to hurricane strength again

Hanna’s getting it together in a hurry. The 2PM advisory took it to the threshold of hurricane force — a 70 MPH tropical storm. It’s also started heading north at 20, a bit earlier than the forecast track first pegged it, too — which may have implications for the forecast track at 5PM.

So far there’s been some decent, if short-lived, rain, heavy at times through the area. Bands have stopped and started — typical of a tropical system. A third squall is about to come on shore now; these will increase in frequency and strength as time goes on. Nothing out of the ordinary so far, though. Post some of your observations in comments — I’m curious to see what you’re seeing.

Radar is rolling in the Charleston Weather broadcast, and I’ll have skycam shots at times too. Back to the air I go…

8am: Increasing divergence ahead of landfall

8am Hanna Computer Models

Here’s the 8am model runs. Note the increasing amount of divergence ahead of Hanna’s landfall. There’s still reasonably strong agreement for the Horry County landfall scenario, but I would not be surprised to see the track jog west a bit more before it’s all said and done.

The 8:00 advisory slows Hanna’s forward motion down ever so slightly (to 18 MPH instead of 20). It’s still headed northwest. Winds are still 65 MPH, but the pressure is down a bit more. Satellite imagery is indicating that the shear has backed off some; note the gigantic plume of convection trying to wrap itself around the center. A hurricane at landfall is reemerging as a possibility.

Stay tuned…

11am: Hanna barely clinging to tropical characteristics

Hanna’s looking rough this morning. It’s back down to 65 MPH winds, and there’s a lot of speculation that Hanna is becoming extratropical. NHC acknowledges Hanna’s struggle to remain tropical in the discussion:

VERY DRY AIR ASSOCIATED WITH THE UPPER-LEVEL LOW OVER THE
NORTHWESTERN BAHAMAS IS CHOKING OFF CONVECTION NEAR THE CORE OF
HANNA…AND THE CYCLONE HAS A VERY SUBTROPICAL APPEARANCE.
CONVECTION HAS DIMINISHED SUBSTANTIALLY OVER THE PAST 6-12 HOURS
AND THE HIGHEST FLIGHT-LEVEL AND SFMR WINDS HAVE COME DOWN AS WELL.
BASED ON SOME 52 KT SFMR WINDS AROUND 11Z…THE INITIAL INTENSITY
IS LOWERED TO 55 KT.

Here’s the latest track, which returns more to the rightward path that we started seeing emerge during the day yesterday before the 11:00 came out:

The wind field is still pretty broad — 310 miles, to be exact — but largely to the north and northeast. We in Charleston still stand a decent chance of seeing tropical storm force winds for a time, and some rain, but with the dry air influencing the storm as well as the continued rightward bias in the models, impacts along our coast will be lessened.

News 2 reports that Gov. Mark Sanford has called for voluntary evacuations of Horry and Georgetown counties; he also said that Hanna might be a “dress rehearsal for a thing called Ike.” Ike is bothersome to me; I’m crunched for time now but will have more later on.

11 PM: Hanna begins northwest turn; watches likely tomorrow

Tropical Storm Hanna 11PM Advisory 09/03:  Satellite Photo

The 11PM advisory is now out on a steadily reorganizing Hanna. Winds remain around 65 MPH, and pressure is sticking around 989 millibars. The Turn has really started to happen, as NHC states forward motion is north-northwest at 13 MPH.

The Track

Tropical Storm Hanna 11PM Advisory 09/03:  Track + Uncertainty Cone

The track seems to have shifted a bit more leftward before landfall; there’s still a fair bit of uncertainty. In the discussion, NHC acknowledges low confidence in the track, citing some spread in the forecast models.

Tropical Storm Hanna 11PM Advisory 09/03:  Forecast Models

There’s good consensus for a turn to the north and then the northeast; the big question is where it will happen. There’s decent consensus heading toward Wilmington, but there’s spread on the western periphery of the consensus — including a HWRF model that generally gets a fair bit of weight from NHC forecasters — hence the uncertainty and the slight leftward jog in the track.

NHC is saying that hurricane watches are likely for a “large portion of the southeast US coast” by tomorrow morning. It’s probably safe to assume that we in Charleston will be included in this watch.

It’s worth noting that the storm will be relatively short-lived; it’ll be increasing in forward speed throughout its approach. In Charleston, it’s likely that Hanna will have largely cleared the area by Saturday night. This is good for reducing the threat of severe flooding. There will still be heavy rains, but at least they will be short-lived.

Effects

Charleston should start feeling effects from Hanna as Friday wears on. As it gets closer, winds will increase. I’ve been able to use an experimental forecast wind field product as a decent guideline for what we might see here.

Tropical Storm Hanna 11PM Advisory 09/03:  Forecast Wind Field

The forecast says that we’ll see some of the worst of the weather Friday night into early Saturday morning, as the center passes within 75 miles or so of Charleston. Sustained winds of 58 miles per hour or greater — as indicated by the purple shading in the map above — are possible for a brief period. As mentioned above, rain totals will probably hit 6″ in some places, but this won’t be a storm that sits and spins and dumps 30″ of rain like a Fay over Florida.

Again, a lot of this is contingent on something resembling the current track holding. There’s more time for stuff to wobble back and forth, and Charleston is still in the cone of uncertainty, so there’s still stuff to watch. However, the direct strike scenario is looking less and less likely.

Closures, etc.

Keep an eye to media outlets and other sources for closure information in the Charleston area tomorrow, as I expect most of those closures (or lack thereof) would be announced during the day. A good resource for this is the @news2 Twitterstream.

Check out Lowcountry Bloggers’ Storm Buzz

The Lowcountry Bloggers roundup site has launched Storm Buzz, an automated feed of hurricane-related posts from the Lowcountry blogosphere. This is a good one-stop resource to see what Charleston bloggers have to say about Hanna and Ike.

Speaking of Ike…

Ike exploded into a dangerous but equally gorgeous Category 4 storm during the day Wednesday. It’s in a perfect environment for strengthening and could be a 5 before it’s all said and done. It’s expected to weaken to a 3; tentatively, it’s headed to the Bahamas, but there’s a lot of spread and uncertainty. It could recurve out into the sea — which would be ideal, of course — or it could threaten the U.S. within the next five or so days. Ike is one to watch because it’s expected to retain major hurricane status as it traverses the Atlantic, with fluctuations in intensity characteristic of huge storms.

For now, though, all eyes will continue to be on Hanna as she makes her move toward the coast. I’ll have more in the morning, probably shortly after the 8am advisory unless there’s a major shift in track that needs immediate attention.

Coverage Continues

Another video briefing will be broadcast at about 9:15 PM, with a roundup of the day’s information and hopefully a better fix on what Hanna’s going to do. She’s still got a history of behaving badly and needs to be watched closely.

Coverage will be more frequent as conditions deteriorate; I’m planning on bringing in additional folks to assist with coverage. Additional streams are planned for as long as power is viable. Now’s the time to follow @chswx and my own personal Twitter account for information and accounts of the storm, too.

And ’round and ’round we go…

Tropical Storm Hanna: 5am

Hanna continues to frustrate folks here in Charleston from just northwest of Haiti as it does a little loop-de-loop (it’s already completed one) over the water, waiting for the high pressure system to build in, pick it up and whisk it off to the northwest. The good news is that it’s still on a slow weakening trend; this morning’s satellite image, depicted above, has her looking like a flat-out mess. The thunderstorms are fairly well-separated from the center; it’s amazing it’s maintaining 60 MPH winds as it interacts with Hispaniola.

Because The Turn hasn’t happened yet, we still are stuck in a wait-and-see pattern. This is frustrating because as NHC’s stated before, we won’t have any idea of exactly where landfall will happen until this thing starts to get going.

The 8am model runs showed a wild rightward shift in almost every model, probably as a result of Hanna’s eastern motion. Time will tell if this shift is anomalous or shows more of a permanent rightward trend. The 2am models started to demonstrate more rightward movement, but the 8am ones are the first time that I’ve seen the HWRF and GFDL models tack as significantly northward as they have.

Tropical Storm Hanna: 5am

The official forecast should look pretty familiar to you at this point, if not a smidge more rightward than previous tracks. Will be interesting to see what 11am brings.

I won’t be blogging all that often today; keep an eye to the Charleston Weather Twitter for updates throughout the day. I’m going to do a video briefing at 9:30 tonight; it won’t last too terribly long unless there are significant changes to discuss (and I’m willing to bet there might be). Back to waiting!

2PM: Hanna The Meanderer…for now

Apologies for the later post; the day job has been hectic with storm stuff as well.

Tropical Storm Hanna’s been caught in something of a steering purgatory this afternoon; it continues to rain very heavily on the Turks and Caicos. As of the 2PM advisory, it’s moving SE at 2 MPH. We’re all awaiting the ridge of high pressure to build in and take it away — but it’s all a wait and see, still.

Intensity Rollercoaster

Hanna’s also been in a weakening trend; Gustav’s outflow has been negatively affecting it most of the day, having a great deal of its northwestern quadrant sheared off, helping to weaken the storm to tropical storm status earlier in the day. It’s held on as a 70 MPH tropical storm, so when the shear lets up, there won’t be much inhibiting it to becoming at least a minimal hurricane again.

This weakening has thrown a wrench in a lot of the forecast, though. The 11AM forecast discussion demonstrates significant uncertainty in the intensity forecast — it could barely hang on as a Category 1, or break free from the shear and blossom into a Category 3:

HOWEVER…GIVEN THE PRESENT LACK OF
ORGANIZATION…IT IS DIFFICULT TO KNOW HOW MUCH STRENGTHENING IS
POSSIBLE. THE NEW OFFICIAL FORECAST IS LOWER THAN THE PREVIOUS
ADVISORY BUT SHOWS HANNA BECOMING A CATEGORY ONE HURRICANE IN ABOUT
36 HOURS. IT SHOULD BE NOTED THAT THIS IS A LOW CONFIDENCE
FORECAST. IN FACT…IF ONE CONSULTS THE WIND SPEED PROBABILITY
PRODUCT INCLUDED IN THIS PACKAGE…IT CAN BE SEEN THAT THERE IS
NEARLY AN EQUAL PROBABILITY OF HANNA BEING A TROPICAL STORM OR
HURRICANE AT DAY 3.

A recon flight should shed much more light on Hanna’s structure; a flight’s scheduled for this afternoon and it probably is on the way in as I type. Here’s hoping that information is reflected in the 5PM.

Track Thoughts

The 11am advisory shifted the track back westward a little bit. Here’s the NHC’s map:

The NHC forecast track splits two groupings of model guidance down the middle. Here’s the high-carb meteorological pasta as of 3:15:

Computer Models at 3:00 Tuesday

One camp — with tighter agreement, I may add — takes an even more westward tack, bringing the center of Hanna onshore to central Georgia. Notably, the GFDL and HWRF models favor this scenario, with the GFDL taking a Category 3 just north of Jacksonville Friday. HWRF is a bit weaker, expecting a Category 2 storm. The other camp favors a Charleston-to-Myrtle Beach swath primarily. It’s a bit more divergent than the other two camps in terms of exact points, but remember, it’s still too early to get caught up in little jogs here and there. NHC has not adjusted the track much in part because Hanna’s size and intensity, as well as where it begins its movement from — remember, the storm has been meandering aimlessly southeast — has some bearing on how much and how quickly the expected high pressure will influence it.

Emergency Preparation

I caught Raymond from News 2’s tweets from the Charleston County EOC meeting. EOC has switched to OPCON 3, which activates the emergency operations center and indicates that an emergency situation is imminent. Mayor Riley is giving a press conference at 3:30 this afternoon; I recommend keeping an eye on News2’s Twitter. I’ll be watching that and will retweet big nuggets of information accordingly on both @chswx and @jaredwsmith.

Don’t forget about the video briefing tonight, tentatively scheduled for 9:15 PM. Sorry it’s so late in the night; I have obligations (read: class) to attend to from 7:00 to 8:15. This will give me an opportunity to review the 8PM advisory and break things down a bit better.

A special hello to those of you who came from The State — thanks for stopping in, and thanks to The State for syndicating this blog on their Web site! I hope folks are finding this useful; I know I’m enjoying doing it. :)