![]() ![]() These winds tended to displace the storm’s thunderstorms away from its low-level circulation, causing the storm to lack a coherent vertical structure. ![]() What made this particular situation so challenging was wind shear, mainly due to strong upper-level westerly winds in Erika’s environment. If it had been obvious, we would have called an audible and changed the forecast. Of course, knowing whether such errors were going to occur and how to reduce them in real time wasn’t obvious. So the track issues weren’t really a surprise to us. In fact, the average 72-hr track error for all tropical depressions and weak tropical storms is around 155 n mi – just about exactly what the errors for Erika were. Why was Erika so difficult to get right?Įrika was a weak and disorganized tropical cyclone, and weak systems generally present us (and the computer simulations we consider) with tougher forecast challenges. As for intensity, Erika ended up being weaker than forecast the 72-hr intensity forecasts were off by about 20 kt on average, and the official 5-day forecasts called for a hurricane over or near Florida until as late as 2 AM Friday, when it became clear that Erika was going to have to deal with the high terrain of Hispaniola. And nearly all of this error was a rightward (northward) bias – that is, Erika moved consistently to the left of the NHC forecast track. A preliminary verification shows that the average 72-hr track error for Erika was 153 n mi, about 30% larger than the 5-year average of 113 n mi. The NHC official forecast errors were larger than average. So, in the spirit of searching for a tropical storm eureka, in this blog entry we present some of our own post-storm reflections. NHC’s forecasts were questioned while others lamented that NHC’s voice wasn’t strong enough amid all the chatter. Some in the media were accused of overinflating the threat, numerical models were bashed, and some public officials were charged with overreacting. Erika is no different, though there’s been more questioning and criticism than usual, with few components of the weather enterprise spared. After every storm we review our operations with an eye toward improving our products and services. Tropical Storm Erika, coming as it did so close to the beginning of the new college and professional football seasons, is a reminder that Monday-morning quarterbacking is nearly as popular an activity as the sport itself. Posted on SeptemUpdated on September 9, 2015 Erika is expected to reach hurricane status with 75 mph sustained winds as it approaches South Florida on Monday.After Further Review: Tropical Storm Erika That doesn’t mean Erika - the fifth named storm of the Atlantic hurricane season - will sputter out.īy the end of the week, forecast models predict that the storm will intensify. “No significant change in strength is anticipated during the next 48 hours,” the hurricane center said. And it shouldn’t get much worse anytime soon. The good news is that while Erika’s winds will be strong, they’ll be far short of historic.Įarly Thursday, the storm packed maximum sustained winds of 50 mph gusts. The hurricane center predicts 3 to 5 inches of rainfall, with as many as 8 inches in some locales. The bad news is that this means islanders and vacationers will get soaked and then some. Kitts and Nevis, Puerto Rico and both the U.S. Barthelemy, Montserrat, Antigua and Barbuda, St. This progression has led forecasters to issue tropical storm warnings - meaning sustained winds of 39 mph or more are expected in the next 36 hours - for numerous island locales including Anguilla, St. ![]() Its next stop will be in and around the Virgin Islands, before brushing the northern coast of the Dominican Republic on Friday. advisory, the storm was centered about 30 miles southeast of Antigua. Erika started moving over the edge of the eastern Caribbean Sea Thursday morning, according to the National Hurricane Center. ![]()
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