HURRICANE ANDREW TIMELINE – 3 DAYS TO LANDFALL + Watching a large disturbance in the Atlantic
Thirty years ago this afternoon – Friday, August 21, 1992 – Andrew was a solid tropical storm. The 5:00 PM advisory from the National Hurricane Center estimated the winds at 60 mph. Andrew was forecast to reach hurricane strength the next day.
The satellite showed that Andrew was obviously organizing, but it was not a very impressive-looking storm. The computer forecast models the National Hurricane Center most depended on insisted the storm would stay east of the Bahamas through the weekend and certainly not be a threat to Greater Miami.
In those pre-internet days, we didn’t have access to the spaghetti models, such as they were, at the TV station. We relied on the non-public Technical Discussions the National Hurricane Center specialists wrote with each advisory to know what direction the various spaghetti plots indicated the storm might go. The NHC also had access to other experimental computer models that tried to predict how strong the storm would be in the future, but we didn’t have much confidence in those models at that time.
The most important maps I received every day in the TV weather office were the printouts of a computer forecast model called the AVN – known as the Aviation. Today, the successor to that model is called the GFS for Global Forecast System. It’s the main weather forecast model run by the U.S. National Weather Service.
The maps that I was most interested in showed the general pattern of high- and low-pressure systems at the level in the atmosphere that determined which direction well-developed storms would be steered. The maps arrived in the weather office on an excruciatingly slow printer, and they arrive upside down. When time was of the essence, you had to wrench yourself around or stand on your head to see the details as the maps were coming in.
That Friday, I especially wanted to see how the AVN was going to predict the high-pressure system off North Carolina would develop over the next three days. If the high strengthened, Andrew could not turn north. It would be blocked, and more likely be deflected toward Florida. In addition, a strengthening high likely meant the steering flow toward Florida would be stronger, meaning the storm might move more quickly toward the state. A faster approach speed would mean, obviously, that Andrew could arrive at the Florida coast sooner than we had been thinking.
When the Monday forecast map finally arrived about 3:30 PM, I strained to read the fuzzy print, which would tell me the projected strength of the potential blocking high. When the number finally came into view, my reaction was something like, “Holy crap!” The map look like this.
The high-pressure system was projected to be even stronger than I had imagined. An extra-strong high could do more than just block a northward turn, it could also push Andrew south. For the first time, there seemed to be a chance that South Florida could be threatened.
In addition, there was a very practical matter in play. It was Friday. In 1992, most people didn’t have mobile phones, and many South Floridians would head out on their boat or down to the Keys to get away. The new school year would begin in just over a week, so people would want to soak in the end of summer. If Andrew made a turn toward Miami, it would be harder to inform people over the weekend.
I decided that we should discuss the possibility of a hurricane threat in detail on the news that Friday afternoon – not because I forecast Andrew to hit South Florida, but because I thought there was a risk it might. People needed to know there was a possibility they might have to jump into preparation mode if Andrew turned our way.
After the fact, I got credit for being the first one to forecast that Andrew was going to hit South Florida. But that wasn’t the case. I had the flexibility to talk about the risk of Andrew staying on the left side of the cone, to use today’s language. I presented as possibility – I was simply gauging the risk.
That Friday afternoon, my decision to discuss the possibility that we might have to prepare for a hurricane was based solely on communications challenges. I was worried that we couldn’t effectively get the word out over the weekend if Andrew came our way.
News Director Sharon Scott reconfigured the newscasts beginning at 5:00 PM. On the air, I discussed my concern about the high-pressure system and Andrew, and we ran hurricane-preparedness videos that were produced for hurricane specials we had run earlier that year.
And thus began the extended TV coverage of the storm that changed everything. The unimaginable, Category 5 Hurricane Andrew.
At that point, I thought Andrew was more likely to hit somewhere north of Miami, though I wasn't ruling out anywhere as the impact point. But with only 60 mph winds that Friday afternoon, nowhere in my mind did I imagine Andrew’s assault on Dade County with winds of 165 mph and gusts to 200 mph or more.
Looking back, it seems inconceivable that that Friday afternoon Hurricane Andrew was only 2 1/2 days from landfall.
AND IN 2022...
A large tropical disturbance on the far side of the Atlantic has a slight chance of developing as it treks off to the west in the general direction of the northeastern Caribbean islands. Its odds of development are low because it’s plowing into a large area of very dry air including some Saharan dust.
From the satellite view, you can see clumpy clouds over the ocean to the north and ahead of the disturbance. Those are similar to fair-weather clouds we would see over land. The atmosphere is too dry to support rain clouds, which often extend higher in the atmosphere.
While there is a slight chance this disturbance might find a moist enough pocket and develop into a tropical depression or tropical storm at least briefly, the more important effect of this system might be to moisten a corridor in the atmosphere for systems coming behind it.
This time of year, we expect a train of disturbances coming off Africa, of course. The major impediment to development seems to be the dry air at the current time. So when a large system moves into the Atlantic, it has to potential to draw moist air from the south and leave a pathway of atmosphere that is more conducive for development of subsequent disturbances.
In the western Gulf of Mexico, the system that looked like it was going to turn into a tropical storm never got there. In the mid-levels of the atmosphere, in apparently had a decent circulation. But at the surface, where it counts, the circulation never consolidated.
The system moved inland with little consequence. It will be absorbed into a larger northern-type low-pressure system over Texas that will bring significant rain. If it doesn’t all come at once, the rain will be a great counter to the damaging drought conditions that have plagued the state and surrounding areas. Periods of heavy rain are likely so some flooding is possible, however. Everybody in Texas and in the threatened areas needs to stay informed.
Over the next few weeks, we’ll be focused on the Atlantic to see if hurricane season kicks in as the calendar says it should. The moistening of the tropical Atlantic seems to be the key.
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