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Monthly Archives: August 2012

By this time tomorrow, if all goes well with my flight out of Denver, I’ll be in New Orleans. Probably somewhere in the French Quarter. Perhaps drinking a hurricane. (Yes, most bars are open.)

My visit has nothing to do with Hurricane Isaac — I’m not on assignment from PJ Media or anything like that. Rather, this is a long-planned trip, related not to hurricanes but to college football. I’m just flying into NOLA Friday and staying there overnight at a hostel (no idea if they have power; we’ll see how that part goes), before driving up to Baton Rouge on Saturday for the LSU-North Texas season opener at Tiger Stadium. I have no connection to either school, but as an avid college football fan, going to a night game at “Death Valley” has long been on my “bucket list,” and I had an expiring Southwest Airlines travel credit to burn by mid-September, so I decided months ago to use it on a football weekend trip. I considered various games around the country, but once I realized there was an LSU night game, and that I could combine it with a night in the Big Easy, my decision was made.

As you might imagine, I considered cancelling the trip due to the aftermath of Isaac. But after much deliberation, I decided tonight to go ahead with the trip. After all, the game is on, the airport is re-opening, the friend I’m staying with in Baton Rouge has power, and heck, I’ve got these perfectly good football tickets; why let them go to waste? Besides, I imagine Louisiana could use the Labor Day Weekend tourism dollars, in light of all the other trips that are undoubtedly being cancelled.

Anyway, although I’m not going to Louisiana specifically to cover the hurricane, I’m sure I’ll wind up tweeting and blogging some first-hand observations. Meanwhile, if any readers here, from Louisiana or otherwise, have some suggestions about things I should do or see while I’m in town — either hurricane-related or not — please feel free to leave them in comments. And if there’s anything aftermath-related that locals might know, which I should be aware of in terms of planning or safety, please let me know that too!

60,000 Ordered To Flee Imminent Dam Failure

August 30th, 2012 - 12:23 pm

Things have taken a seemingly dire turn in the last hour, as officials have ordered as many as 60,000 people to immediately evacuate from towns along the Tangipahoa River in Louisiana, about 100 miles north of New Orleans, for fear of an “imminent” break in the Lake Tangipahoa Dam.

Hopefully those people get out safely, and hopefully this is not a sign of things to come as Isaac’s torrential rains make their way to streams, rivers and lakes throughout the region.

Stay tuned to NOLA.com and the other local news sites linked in my last post. Also follow me on Twitter, where I’ll post updates as I get them.

P.S. Of note, Britney Spears’s hometown of Kentwood is one of the towns threatened.

LATE UPDATE: The breach is apparently no longer considered “imminent,” and efforts to relieve some of the stress on the dam with a deliberate upstream levee breach in Mississippi appear to be working. However, the evacuations continue as a precaution.

Meanwhile, sadly, Isaac has now claimed its first two reported lives in Louisiana.

[NOTE: Follow me on Twitter for the very latest on Isaac.]
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Before we get into the ugliness of conditions in Louisiana and Mississippi right now, let’s start with something beautiful — a NASA image of a moonlit Tropical Storm Isaac early Tuesday as it approached the Gulf coast:


On to the ugliness. Isaac — now a tropical storm again as it gradually weakens over land — has sloooooooowly crawled northwestward through Louisiana all day, taking 28 hours and counting to complete the journey from the mouth of Mississippi River in Plaquemines Parish to the city of Baton Rouge, which takes 3 hours by car.

Along the way, Isaac has dumped relentless rains — Audubon Park in New Orleans recorded an incredible 19.30″ of rain, 18.70″ of it within a 24-hour period — and pummeled the region with seemingly endless wind and surge. The vast bulk of southeastern Louisiana is without power, and people are stuck in their homes with nothing to do but watch and wait for the storm to finally move out of the area. Listening to WWL radio today, the overwhelming sentiment was simply frustration that the storm wouldn’t get gone.

New Orleans proper appears to have done quite well, as the levees have remained intact and the pumps have worked as planned, both passing their biggest test since Hurricane Katrina. But to the south in Plaquemines Parish, the locally constructed levee did not fare so well. Massive flooding created scenes of devastation that locals, including local officials, described as worse than anything they suffered in Katrina — a symptom of Isaac’s worst-case track, angle of approach, and horrifically slow movement trumping its comparatively lower intensity. The images from Plaquemines are heartbreaking:

Those pictures are, to my mind, a helpful reminder of what the true “worst-case scenario” for New Orleans — which Katrina emphatically was not — would look like, but across a much broader area. As opposed to being trapped in attics or on rooftops hours after the storm, folks are trapped and threatened while the storm is still raging. As opposed to a slow leak, caused by breached levees, which gradually fills the “bowl” to regular sea level (finishing long after the storm leaves), what Plaquemines Parish is experiencing is a rapid, in-storm flash-surge-flood caused by overtopping of the levees, which fills the “bowl” up to, in essence, the level of the storm surge at or near its peak, and then leaves the water there, hemmed in by the very levees that were originally there to keep it out. For this reason, officials are considering deliberately blowing holes in the levees to assist with drainage. That is precisely the sort of scenario envisioned in the pre-Katrina literature about the worst-case possibilities for New Orleans. In NOLA’s case, it would take a Category 3 or 4 storm to do it, but someday it will happen. Folks need to understand that, and not treat “Katrina” as synonymous with “The Worst Thing That Can Possibly Happen,” because that just isn’t so.

Plaquemines’ situation is also an object lesson in why, when authorities order you to evacuate, you evacuate. You don’t sit there and carp about “hype” and “hysteria,” and about how “it’s just a tropical storm” or “it’s just a Category 1″ or “we survived [insert previous storm here], we’ll be fine.” You don’t make up your own amateur weather forecast, in contradiction to the actual experts, based on gut instinct and life experience, and then make life-or-death decisions based on that self-forecast. No. You know what you do? YOU LEAVE. If you’re in a low-lying area vulnerable to surge flooding and the authorities tell you an evacuation is necessary, you get the Hell out of dodge. Period.

The people who stayed behind, despite mandatory evacuation orders, and then ended up predictably needing to be rescued, are endangering not only their own lives, but also the lives of the heroes — first responders, yes, but regular private citizens too — who came to their rescue. That’s inexcusable. However, I’m not saying this to berate them; they’ve suffered enough, and have undoubtedly learned their lesson. I’m saying it to the next group of people who might be tempted to do the same thing when the next storm threatens. Don’t. Do. It.

The disaster in Plaquemines occurred because of storm surge, which was almost as bad as Katrina’s for the area — not surprising, considering that Katrina, although more intense with a much bigger surge, made landfall to the east and kept its right-front quadrant away. This storm took a worst-case track, as I keep saying, and only its relative weakness spared the region a much more widespread catastrophe. Can you imagine if Isaac had managed to spin up to a Category 3, and then had done this? Good lord. Thank God for dry air.

Over in Mississippi, Biloxi was hit hard by flooding too, with the mayor confessing he wishes now he had ordered a mandatory evacuation. “I really didn’t anticipate this,” Mayor A.J. Holloway told The New York Times. “There’s a lot more water than I would have thought.” That attitude appears to be common among elected officials in several of the harder-hit areas, and I find it extremely irritating: Isaac’s effects should not have surprised anyone, as they were largely predicted in advance. Anyone who “didn’t anticipate this” was either not paying attention, was ignoring the worst case in favor of more desirable scenarios, or was disregarding the forecast in favor of their own instinct about what a Tropical Storm or Category 1 was likely to be capable of. Not a good plan.

Flooding has also occurred along Lake Pontchartrain, where the combination of storm surge and drenching rain has flooded various communities and subdivisions to varying degrees of severity. That appears to be improving now, but watch out for river flooding as the incredible rainfall totals work their way into the tributaries. This storm isn’t over yet. The National Hurricane Center predicts that it will take about another day to exit Louisiana completely. Ugh. Get the Hell out, Isaac!

Again, for the latest news on conditions in and around New Orleans, check NOLA.com and the local TV station websites. Here are the links to their livestreams:


Another great resource is the awesome WWL radio, which did amazing work during Hurricane Katrina and is doing so again. For Mississippi, check the Sun-Herald; for Baton Rouge, The Advocate.

[NOTE: Follow me on Twitter for the very latest on Isaac. Also, live tidal data here.]
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Hurricane Isaac is still going nowhere fast, sitting and spinning — and maintaining its strength — over the marshes and bayous of southeast Louisiana. Here’s a live radar animation from Weather Underground:

And here’s the current Doppler-estimated rainfall totals for the storm, which are going to be a bigger and bigger problem the longer this thing just sits and spins:

The storm surge is also continuing — heading into a second high tide now — because of Isaac’s persistence. Click here to view live tidal gauge data. Another excellent resource for water level and rainfall data is this Army Corps page.

Thus far, the New Orleans levees and pumps are reportedly holding up fine. A rural stretch of non-Army Corps levees in Plaquemines Parish has been overtopped, threatening some folks who did not heed the mandatory evacuation there.

For the latest news on conditions in and around NOLA, check NOLA.com and the local TV station websites. Here are the links to their livestreams:


And again, for the latest from me, follow me on Twitter.

Isaac Makes Second Louisiana Landfall

August 29th, 2012 - 5:16 am

[NOTE: Follow me on Twitter for the very latest on Isaac. Also, live tidal data here.]
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Exhausted from several short nights tracking Hurricane Isaac, I inadvertently dozed off on the couch just as I was about to publish a concerned update that was going to begin by referening this computer model animation, which shows Isaac drifting aimlessly west for about 12-18 hours, then dipping south, further back into the Gulf (but still close enough to dump additional rain on Louisiana), before at last making a final landfall in 30-36 hours and then recurving north and away. Such a scenario would likely be a disaster for New Orleans and environs, producing even more rain than the 12-20″ that is currently being forecast and allowing Isaac to maintain its strength or even intensity a bit as its center remains over the Gulf.

Thankfully, four hours later, that scenario has already been overtaking by events. Isaac has made its second landfall, west of Port Fourchon, LA, and is now meandering northwest. The eye is set to pass just west of New Orleans over the next several hours, bringing the heaviest wind and rain over the city.

The steering currents remain weak, and Isaac may continue to meander a bit. Certainly it will continue to move slowly, dumping copious rains and lashing the area with heavy winds. Even though it’s now solidly inland, Isaac may not immediately weaken tremendously, because it’s basically sitting over a swamp, and still sucking in moisture from the Gulf. Flat, moist “land” like the bayous aren’t particularly disruptive to a hurricane’s circulation. So weakening is not expected to begin in earnest just yet. And regardless, the rains will continue.

NOLA’s new and improved pumps are supposed to be able to handle 0.5″ per half-hour, but at some point, the massive, 20″+ amounts of rain being forecast have to become a problem. I’m even less an expert on this than I am on the hurricanes themselves, but I am a bit concerned, while hoping for the best. Cross your fingers that NOLA will come through this okay.

Anyway, from what I’ve read, the biggest problem in Louisiana right now is that an 18-mile stretch of levee in Plaquemines Parish has been over-topped. New evacuations are underway, mid-storm apparently. That sounds like a dangerous situation for sure.

On the bright side, the storm surge in Shell Beach, Louisiana has apparently peaked at 11 feet, and is now dropping:

The water level is still rising in and near Lake Pontchartrain, though. (See also here.)

Again, to track the storm live via satellite, radar and water gauges, click here.

Also, for the very latest, follow me on Twitter.

Isaac Slowly Spins Off Louisiana Coast

August 28th, 2012 - 11:21 pm

[NOTE: Follow me on Twitter for the very latest on Isaac. Also, live tidal data here.]
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Hurricane Isaac officially made landfall in Plaquemines Parish about 40 minutes after I prematurely called it, basically because its eye expanded and backed into the coast. It then moved back off the coast, and is currently sitting over the water, spinning slowly offshore:

With the eye remaining over water, Isaac still has a chance to maintain its strength, or even perhaps strengthen a little, for quite some time. Even once it moves over the swampy bayous, that may remain true. According to the 11pm NHC discussion, little change in strength in expected over the next 12 hours. (Note: the barometric pressure has actually dropped to 968 mb.)

So, at this speed, all of southeastern Louisiana is going to take an extended battering, both from the winds and, more importantly, from the rain — possibly as much as 20 inches or more — and storm surge. (The surge is still rising at Shell Beach, LA, for instance.)

Here are some high-resolution satellite images of the landfall:

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[NOTE: Follow me on Twitter for the very latest on Isaac. Also, live tidal data here.]
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Category 1 Hurricane Isaac has made landfall in Plaquemines Parish, Louisiana, near the Mouth of the Mississippi River. Here’s a screen grab of the WunderMap radar:


[UPDATE: I may have spoken too soon. Sure looked on radar like it had made landfall, but now it seems to be stalling or moving very slowly just offshore, and maybe strengthening a bit in the process.


Stay tuned.]

For the very latest, follow me on Twitter.

Also, see below or click here to keep watching the storm surge rise via tidal gauges.

Lots and lots more tidal and lake/river gauges can be found here.

Hurricane Isaac

August 28th, 2012 - 12:47 pm

[NOTE: Follow me on Twitter for the very latest on Isaac. Also, live tidal data here.]
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After confounding storm-watchers by refusing again and again since yesterday evening to officially declare Tropical Storm Isaac a hurricane when there seemed to be ample evidence for an upgrade — particularly this morning at 11:00 AM Eastern, when recon data showed flight-level winds of 101 mph, surface winds (via a dropsonde) of 81 mph, and a barometric pressure of 976 mb — the National Hurricane Center finally pulled the trigger in a special 12:20 PM EDT update:



So, there you have it. Hurricane Isaac, a Category 1, bearing down on southeastern Louisiana, on what would be a catastrophic track if this were a major hurricane. Thank goodness it’s not; thanks goodness for dry air. That said, Isaac may yet strengthen a little more before landfall tonight. But the main threats will be storm surge and rainwater flooding, and perhaps inland wind and widespread power outages (particularly if Isaac does intensify just before landfall, which would imply that it will remain strong over land for a longer period of time).

To watch Isaac on satellite and radar, and to track the surge with live tidal gauge data, view the post below.

And again, for the very latest, follow me on Twitter.

UPDATE, 2:30 PM: All along the Louisiana and Mississippi coasts, the water is rising as the storm surge comes in — even as it “should” be receding, now that we’re past high tide in most places. Take, for instance, the data from the tidal gauge in Shell Beach, Louisiana (which is located here, for reference). The red line is the water level; the blue line is what the water level “should” be doing, absent Isaac. The green line represents the storm surge (i.e. the red line minus the blue line).

The next high tide throughout most of these areas is around midday tomorrow. (The Gulf of Mexico has diurnal tides.) On the projected track, Isaac will continue piling water onto the shore throughout the ~24-hour period between now and then. If the surge continues to prevent the tide from going out, as it’s doing right now, that next high tide could be a significant problem.

I’ve been playing down the storm surge threat a little bit, comparing it to the “hive, not pimple” phenomenon of Ike and Irene, whose surges were underwhelming as compared to the dire projections. But the trajectory of the green surge line on graphs like the one above, combined with the sheer amount of time Isaac has left to keep driving the surge on shore, has me concerned now.

[UPDATE: The National Weather Service New Orleans office is definitely concerned too. They're labeling this as a potential "extreme" surge flooding event across much of southeastern Louisiana with surge levels of 9 feet or more, which is defined as:

Life threatening flooding possible in areas outside hurricane protection levees and in areas around Lakes Pontchartrain and Maurepas. Sections of west Jefferson, east St Charles and lower Lafourche hurricane protection levees could be over topped. Areas outside of hurricane protection levees will be severely inundated. People not heeding evacuation orders in single family, one or two story homes could face certain death. Many residences of average construction directly on the coast will be destroyed. Widespread and devastating personal property damage is likely elsewhere. Vehicles left behind will likely be swept away. Numerous roads will be swamped. Some may be washed away by the water. Entire flood prone coastal communities will be cutoff, perhaps for more than a week. Water levels may exceed 9 feet or more behind over topped levees. Significant storm surge flooding will move well inland especially along bays and bayous. Coastal residents in multi story facilities risk being cutoff for a week or more.

I'm not sure what "could face certain death" means -- are they saying it "could" happen, or that it's "certain" to happen? -- but there's obviously a high level of alarm. Note, though, that the above is definitional language for an "extreme" event of 9-15 feet. It wasn't written specifically for this storm. Still. Bad news.]

The water level is also rising in and near Lake Pontchartrain. (I can’t embed that graph, alas. But go look at it!) FWIW, Katrina caused these gauges to get up in the 9 to 12 foot range.

Lots and lots more tidal and lake/river gauges here. Watch the storm surge in real time.

And — again — for the very latest, follow me on Twitter.

[NOTE: check the blog homepage and follow me on Twitter for the very latest.]
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Tropical Storm Isaac remains at the very cusp of hurricane status, declared “nearly a hurricane” as of 7:00 AM. Its barometric pressure remains more typical of a Category 2 hurricane, and the most recent NHC discussion, at 5:00 AM, stated that “THE INNER CORE CIRCULATION IS BECOMING BETTER DEFINED…AND STRENGTHENING MIGHT BE IMMINENT.” (Stop me if you’ve heard that one before. What a confounding storm to forecast!) Yet for now, on the morning of the day it will hit the U.S. mainland, Isaac remains stuck at 70 mph. I confess I’m a bit surprised the NHC hasn’t just gone ahead and declared it a hurricane — it’s so close, either decision would probably be justifiable — and then let the year-end Tropical Cyclone Report retroactively downgrade it if necessary. But they’re playing this one by the book.

Whether it hits as a 70 mph tropical storm or a 75 mph hurricane, Isaac’s effects will largely be the same. I still think inland flooding and perhaps inland wind will be the biggest impacts; storm surge is also a threat. If Isaac does start to (finally) rapidly intensify, and end up approaching Cat. 2 status, its immediate landfall effects will be a bit more severe. But either way, this seems likely to be a serious, but non-catastrophic, hit. (The inland flooding is the one thing that still has some potential to be catastrophic, or nearly so; we’ll see.) Folks in the storm’s path should remain hunkered down, if that’s what they’ve chosen to do, and not let down their guard. But the media should also dial back the hype, as I wrote last night. This isn’t going to morph into an apocalyptic hellstorm in the final hours before the landfall. It genuinely did have that potential, but thanks to some lucky dry air entrainment, it didn’t realize its potential, despite generally near-perfect environmental conditions. So now let’s not pretend a gas station roof blowing in the wind, or some predictable storm surge in an extremely flood-prone coastal area, or inevitable widespread power outages, constitutes armageddon, mmkay?

Anyway… as I did during Irene, I thought it would be helpful to post some live tidal-gauge data here, as a sort of “one-stop shop” for tracking Isaac’s storm surge. But then I realized: why stop there? How about a one-stop shop for landfall-watching data generally? So, before we get to the tidal gauges, how about some satellite and radar maps?

Lots of images after the jump…

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Isaac Stubbornly Refuses To Become A Hurricane

August 28th, 2012 - 12:10 am

[NOTE: check the blog homepage and follow me on Twitter for the very latest.]
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For the third consecutive advisory, the belief that Isaac might imminently become a hurricane was not vindicated at 11:00 PM EDT, as the storm’s winds were held at 70 mph, just shy of hurricane strength — even as the pressure dropped to 979 millibars, which is usually more typical of a borderline Category 1/Category 2 hurricane.

In this sense, Isaac is reminiscent of a poor man’s Hurricane Ike, which at one point had a pressure of 944 mb, typical of a borderline Category 3/Category 4 hurricane, yet its winds refused to budge from 100 mph (borderline Category 1/Category 2). People kept insisting that Ike’s winds would inevitably “catch up” to the pressure, in a burst of rapid strengthening that was always just around the corner. There was also fear that the pressure, plus the storm’s immense size, would lead to an epic storm surge well out of proportion to the winds and category. Similar fears are being expressed with Isaac. Yet Ike’s winds never did “catch up” with its pressure, and the surge underwhelmed — it was a hive, not a pimple.

Likewise, another “I” storm — last year’s Hurricane Irene — at one point had a pressure of 942 mb, typical of a Category 4, but winds of 110 mph that never “caught up” with the pressure. Indeed, Irene eventually weakened to a minimal hurricane, 75 mph, with a pressure of 958 mb (typical of a mid-range Category 3), and then to a tropical storm, 60 mph, with a pressure of 966 mb (typical of a high-end Category 2). Irene, too, produced fears of a storm surge vastly out-of-proportion to its wind and category — yet the reality again underwhelmed.

I’m not saying that Isaac is Ike redux or Irene redux — every storm is different — and I certainly think folks in surge-prone areas should prepare for the worst (or, more precisely, should already have prepared for the worst), including by evacuating if appropriate. But the parallels do give me some pause about the current storm-surge predictions. We shall see.

Meanwhile, I still suspect Isaac will become a hurricane overnight — but I can’t help but wonder, what if my Thursday-morning post, “Might Isaac Never Become A Hurricane?,” turns out to be accurate? I had given up on the notion days ago, but with less than 24 hours until landfall, the storm is running out of time!

In any case, it makes little difference — a 70 mph tropical storm and a 75 mph hurricane are basically the same thing. The question isn’t whether Isaac will become a minimal hurricane, but whether it will have the type of overnight/morning rapid intensification phase, just before landfall, foreseen by the GFS earlier today. It still may. And intensification at landfall would make the storm feel like much more of a beast, as I explained earlier. But every time you think this storm is about to go “rapid,” dry air keeps interfering. That’s very good news for New Orleans & environs, and although I feel a certain dread about the inevitable cries of “OVERHYPE!!!1!” if that good luck continues, it’s obviously best for everyone if it does.

I’ll try to post an update in the morning sometime around 8:00 AM Eastern. Maybe Isaac will finally be a hurricane by then. Stay tuned, as they say.

P.S. One final note. Up until now, talk of various worst-case scenarios, or at least of very-bad scenarios, has been justified and proper, because of the forecast uncertainty and the very real possibilities of calamity that existed. Several people have asserted to me that there was “no evidence” Isaac would become a major hurricane, but that’s just categorically false: multiple reliable computer models had multiple consecutive runs showing a Category 3 or stronger hurricane making landfall on the Gulf coast. Those models weren’t invented by TV pundits or weatherbloggers. They were real, and they were scary. Moreover, although this storm has proven to lack intensity, it’s taking a horrific track from NOLA’s perspective, and if it weren’t for several very persistent dry-air entrainments — something that just can’t be predicted with any degree of certainty — we really could be looking an extremely dire situation right now. This was a close-run thing. The large-scale conditions for strengthening to a major hurricane (good outflow, low shear, warm waters) were nearly perfect; only hard-to-predict small-scale features (dry air, core structure) prevented Isaac from reaching its potential. Meteorologically speaking, particularly in light of the track, this was closer to a disaster than the overhype-troll crowd will ever understand.


Barring significant overnight intensification, the media must dial back the “hype” in the morning. Unless we all wake up to an exploding Isaac that’s finally worked out its dry-air and inner-core issues and is seriously ramping up just before landfall, the worst-case scenarios in terms of intensity will no longer be valid or relevant. So it’ll be time to stop talking about them, and indeed, to explicitly acknowledge that they’re now off the table. Yes, there will still be a significant (though, let’s not kid ourselves, probably not catastrophic) storm surge, plus major threats in terms of inland flooding (that one COULD be catastrophic) and perhaps inland winds, power outages, etc., etc. But those concerns are of a different order from the apocalyptic fears many of us justly felt when we saw model maps like this. It insults readers’ and viewers’ intelligence to treat “ordinary” storm impacts, like typical coastal flooding, downed trees, widespread power outages, gas station roofs blowing in the wind, etc., as epic events of grave significance on par with the sort of impacts we originally feared. This is where media gets hurricanes wrong: not by discussing worst-case scenarios early on, when they’re still plausible and in fact the public needs to be aware of them, but by failing to back off the “hype” once it’s clear that the worst isn’t happening. There’s a reason you’ve seen this blog steadily backing off the worst-case talk today: I always try my best to “keep it real,” and call it like I see it — and it’s become increasingly clear to me that this storm, while very serious (all hurricanes, and near-hurricanes, are!), isn’t going to be an epic catastrophe, after all. It could have been, but now it’s very likely not going to be. I try to make sure my coverage reflects that once it becomes clear. I hope the MSM will do so too.