The Climate Prediction Center predicted moderate chances that a tropical depression or a storm will form in the Caribbean during the last week of May.

Even if no storm develops, the prediction signals that the Atlantic is becoming primed for tropical activity as June 1, the official start of the six-month hurricane season, nears.

“It’s something to pay attention to. It might be a little earlier than normal,” said Eric Blake, a specialist with the National Hurricane Center.

While the two-week tropical hazard forecasts by the Climate Prediction Center are not very accurate now, meteorologists there are working with the National Hurricane Center to improve them. Within a few years, the two agencies plan to start making a joint two-week forecast, with the hurricane center taking the lead on the first week and the climate center handling the second, said Blake, who gave a presentation about the project at the Governor’s Hurricane Conference here on Tuesday.

He said the hurricane center began working with the climate center on the two-week outlook shortly after the busy 2005 hurricane season.

“The challenge has really been eliminating the false alarms,” Blake said.

The two-week outlook mostly relies on thunderstorm activity around the global tropics to predict where chances are increased for a tropical storm or depression to form. Clusters of thunderstorms occasionally move around the globe in a weather pattern called the Madden-Julian Oscillation or MJO. When the thunderstorms are over the Caribbean and Africa, the chances for tropical storms to develop in the Atlantic increase, Blake said.

But because weather is so variable, forecasts that extend beyond a week tend to have a large margin of error. The five-day forecast for tropical activity, however, is getting much better.

Blake said the hurricane center will experiment this year, in-house, with predicting the formation of tropical storms five days in advance. If the forecasts pan out, weather buffs, fishermen, shipping businesses, emergency planners and those in the oil and gas extraction industries could benefit from those forecasts beginning next year.

By Kate Spinner

The forecast team of Philip Klotzbach and William Gray released its early hurricane season forecast for 2012, saying that it is dispensing with the usual numerical forecast for the number of storms. Instead, Klotzbach and Gray issued their forecast in terms of the probabilities “of the key factors influencing the hurricane season.”

The reason for the change, they say, is the difficulty forecasters have in determining whether an El Niño will occur in the Pacific, which impacts the Atlantic hurricane season.

The team says there is a 45 percent chance that climate conditions that have persisted since 1995 will continue along with no El Niño development in the Pacific. These conditions include warmer water temperatures in the tropical Atlantic and reduced vertical wind shear—conducive conditions for hurricane formation.

Should that be the case, hurricane activity would be 140 percent of the average season, which would be characterized as 12 to 15 named storms, seven to nine hurricanes and up to four major hurricanes (Category 3, 4 or 5 with sustained winds of 111 mph and greater), the forecasters say.

The team says there is a 30 percent chance that Atlantic wind circulation remains unchanged and a significant El Niño occurs, which would reduce the tropical-cyclone season to approximately 75 percent of the average season. That would be 8 to 11 named storms, three to five hurricanes and one or two major hurricanes.

There is a 15 percent chance that current Atlantic wind conditions could become unusually strong, and no El Niño occurs, which would lead tropical-cyclone activity of up to 180 percent of average hurricane season—about 14 to 17 storms, 9 to 11 hurricanes and four to five major hurricanes.

And the forecasters say there is a 10 percent chance that current Atlantic wind conditions weaken and a significant El Niño develops, which would reduce the tropical-cyclone activity to 40 percent of the average season—five to seven storms, two to three hurricanes and possibly one major hurricane.

For 2011, the CSU forecast team had predicted that the hurricane season would be well above average. In June the team called for 16 named storms, nine hurricanes and five major hurricanes. The season produced 19 named storms, seven hurricanes and three major hurricanes.

By Mark E. Ruquet, PropertyCasualty360.com

The 19 tropical storms represent the third-highest total (tied with 1887, 1995, and 2010) since records began in 1851 and is well above the average of 11. However, according to NOAA, the number of hurricanes and major hurricanes is only slightly above the average of six and two, respectively. This year’s totals include a post-storm upgrade of Tropical Storm Nate to hurricane status, and the addition of a short-lived, unnamed tropical storm that formed in early September between Bermuda and Nova Scotia. This unnamed storm, along with several other weak, short-lived named storms, could have gone undetected without modern satellite technology.

Irene was the lone hurricane to hit the United States in 2011, and the first one to do so since Ike struck southeast Texas in 2008. Irene was also the most significant tropical cyclone to strike the Northeast since Hurricane Bob in 1991.

“Irene broke the ‘hurricane amnesia’ that can develop when so much time lapses between landfalling storms,” said Jack Hayes, Ph.D., director of NOAA’s National Weather Service. “This season is a reminder that storms can hit any part of our coast and that all regions need to be prepared each and every season.”

As far as landfalling major hurricanes (Category 3, 4 or 5 with top winds of 111mph and greater) are concerned, the lull continues. 2011 marks a record six straight years without one hitting the United States. The last one to do so was Wilma in 2005. Nonetheless, wind is not the only threat with tropical systems as proven by Irene and Lee, which caused deadly and destructive flooding. On average, more than half of the fatalities related to tropical systems are due to flooding.

Hayes said Hurricane Irene is an example of increasing accuracy in forecasting storm track. Its landfall in eastern North Carolina and path northward were accurately predicted more than four days in advance by NOAA’s National Hurricane Center using information from weather satellites, hurricane models, aircraft observations, and other data. NOAA’s forecasts allowed emergency officials to plan necessary evacuations and sparked individuals to take safety precautions. But a weaker-than- at landfall also highlighted the challenges that remain in forecasting storm intensity, NOAA officials said.

“Improving intensity forecasts is a focus of ongoing research and is part of NOAA’s Hurricane Forecast Improvement Project,” said Frank Marks, Ph.D., director of NOAA’s Hurricane Research Division. HFIP bridges research and operational components to better anticipate rapid changes in storm intensity and its goal to extend track forecasts from the current five days to seven days.

“Although the 2011 hurricane season has ended, our need to prepare for disasters hasn’t,” said Craig Fugate, administrator of the Federal Emergency Management Agency. “Being prepared for all kinds of hazards, from hurricanes to blizzards to tornadoes, is a year-round activity. We encourage all members of the team, especially the public, to continue to prepare for emergencies by staying informed of forecasted weather events, making an emergency plan, and building your emergency preparedness kit. Visit Ready.gov to learn more.”

NOAA said it will issue its initial outlook for the 2012 hurricane season in May just prior to the official start of the season on June 1.

Andover, Mass.-based WSI, a member of The Weather Channel Cos., released a forecast of 15 named storms in May. Its prediction for eight hurricanes and 4 intense hurricanes (Category 3 or more) remains unchanged.

With nine named storms already this year, well before the midpoint of the season, WSI “had no choice but to increase our named storms forecast from 15 to 18—and the current pace suggests that even this number may be too low,” says Todd Crawford, WSI’s chief meteorologist.

Warmer-than-normal Atlantic water temperatures, very low surface pressures in the hurricane development region and no El Nino event all bode well for a “quite active” tropical activity, Crawford adds.

Crawford says the Gulf Coast is under the greatest threat for the remainder of the season, as “persistent atmospheric blocking in the North Atlantic” that has prevented U.S. landfalls the past two years relaxes as September arrives.

“Our recent good fortune in avoiding land-falling hurricanes is not likely to last,” he says.

Forecasters at the National Oceanic and Atmospheric Administration (NOAA) said they are more confident that 2011 will be an active Atlantic hurricane season. They now expect three to five of this season’s storms could turn into major Category 3 or above hurricanes, with winds of more than 110 miles per hour

NOAA’s Climate Prediction Center, a division of the National Weather Service, updates its Atlantic hurricane season outlook every August.

“The atmosphere and Atlantic Ocean are primed for high hurricane activity during August through October,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at the Climate Prediction Center. “Storms through October will form more frequently and become more intense than we’ve seen so far this season.”

Key climate factors predicted in May continue to support an active season. These include: the tropical multi-decadal signal, which since 1995 has brought favorable ocean and atmospheric conditions, leading to more active seasons; exceptionally warm Atlantic Ocean temperatures (the third warmest on record); and the possible redevelopment of La Niña. Reduced vertical wind shear and lower air pressure across the tropical Atlantic also favor an active season.

Based on these conditions and on climate model forecasts, the confidence for an above-normal season has increased from 65 percent in May to 85 percent. Also, the expected number of named storms has increased from 12-18 in May to 14-19, and the expected number of hurricanes has increased from 6-10 in May to 7-10.

Across the entire Atlantic Basin for the whole season – June 1 to November 30 – NOAA’s updated seasonal outlook projects, with a 70 percent probability, a total of:

14 to 19 named storms (top winds of 39 mph or higher), including:
7 to 10 hurricanes (top winds of 74 mph or higher), of which:
3 to 5 could be major hurricanes (Category 3, 4 or 5; winds of at least 111 mph)
These ranges are indicative of an active season, and extend well above the long-term seasonal averages of 11 named storms, six hurricanes and two major hurricanes.

The Atlantic basin has already produced five tropical storms this season: Arlene, Bret, Cindy, Don and Emily. All eyes this week are on Emily, which continues to develop and move towards the United States.

The last hurricane to make landfall in the United States was Ike in 2008. Last year saw above-normal hurricane activity, but none made landfall in the United States.

August through October are peak months of the Atlantic hurricane season, and officials are urgings people not to be lured into a false sense of security by the lack of hurricanes so far this year.

Before the June 1-Nov. 30 season got under way, residents of hurricane danger zones were warned by many forecasters they faced a very high probability of a major hurricane making landfall along the U.S. coastline.

That has not happened and with the most active part of the season winding down in the next two weeks or so, the chances of a major impact on the U.S. mainland or on energy interests in the Gulf of Mexico are ebbing.

“If you just use (U.S.) landfall as a criteria and did not pay attention to the numbers, you’d think this was a really quiet year,” U.S. National Hurricane Center director Bill Read told Reuters.

“A couple of relatively minor impacts and some flooding and that’s what we’d have to show for it,” he said.

Read said 2010 was still likely to go down in the record books as another in a string of exceptionally busy seasons, however. The United States had just been very lucky in not getting hit by a major hurricane.

Hurricane Earl, which became a Category 4 hurricane on the five-step Saffir-Simpson scale of storm intensity, came the closest by approaching to about 100 miles off North Carolina and southern New England last month, Read said.

“That’s a relatively narrow escape if you look at it from the global perspective,” he said.

Read also noted that the 2010 Atlantic season had taken a high toll in flood and mudslide deaths in Central America and Mexico, meanwhile.

An average season produces about 10 storms, of which six become hurricanes. This year has seen 15 named storms so far, with Otto forming as a subtropical storm over the Western Atlantic Wednesday, but posing no immediate threat to land.

U.S. oil and gas installations in the Gulf of Mexico have been virtually unscathed by this year’s hurricane season, which posed an early threat to efforts to control and clean up oil spewing from the ruptured Gulf of Mexico well owned by BP Plc, which was the worst oil spill in U.S. history.

Read said the eastern portion of the Gulf and the Caribbean, along with southern Florida, were not totally out of the woods yet, however.

With sea surface temperatures still very high, conditions for storm or hurricane formation, especially over the Caribbean, remain favorable, Read said.

Tropical cyclones draw energy from warm sea water.

Read expressed particular concern for impoverished and nearly treeless Haiti, saying it had just been “an amazing stroke of good fortune” that the earthquake-ravaged nation had not been hit by a major storm so far this year.

“They’re so vulnerable, it wouldn’t take much to cause a crisis,” he said.

LANDFALLS TOUGH TO PREDICT

Though forecasters have cut their errors in predicting the track of a hurricane, Read said there were still problems in terms of their long-term “skill” in pointing to landfalls.

In June, for instance, leading U.S. forecasters at Colorado State University had said the chance a major hurricane would make a landfall on the U.S. coastline this year was 76 percent compared with the last-century average of 52 percent.

But Read said it was not surprising no major hurricanes had hit the U.S. coast directly, given global oceanic and atmospheric conditions.

“It’s highly dependent on where they form and the steering currents at the time,” Read said, when asked about the ability to predict landfalls.

“With the weather pattern that was in place and the fact that these (storms) formed so far out to the east, it’s not surprising that they turned off to the north,” he said.

“As soon as you find a weakness in the big high, the Bermuda-Azores high, you’ll get that effect. That’s why Igor and Danielle and Julia among others went straight north pretty much.”

The weather pattern known as La Nina was also a factor behind this year’s hurricane season, since it brought wind conditions that foster Atlantic hurricanes.

La Nina is a cooling of the sea surface in the tropical Pacific and has had an impact on global weather. It tends to reduce the shearing winds that can disrupt nascent storms in the Atlantic.

“In the eastern Pacific this will be one of the quietest seasons on record,” Read said. “That’s what you see in a La Nina pattern, a lessening of storms in the Pacific and a greater chance of storms in the Atlantic.”

By Tom Brown
October 7, 2010
(Editing by Pascal Fletcher and Eric Walsh)

Read more: http://www.insurancejournal.com/news/national/2010/10/07/113880.htm#ixzz11hVMqJ5v

The National Oceanic and Atmospheric Administration (NOAA) said it now anticipates 14 to 20 tropical storms, with eight to 12 expected to strengthen into hurricanes.

Four to six of these storms are expected to become “major” hurricanes, which are defined as Category 3 or higher and can have winds of more than 110 mph.

In their previous forecast, NOAA had forecasted 14 to 23 tropical storms, with eight to 14 developing into hurricanes, and three to seven escalating into major hurricanes.

The revision comes as a result of a lower-than-expected number of storms during June and July.

So far, the 2010 season has seen just three tropical storms, with only one reaching hurricane strength.

According to Gerry Bell, the lead hurricane seasonal forecaster with NOAA’s Climate Prediction Season, “We’re still predicting a very active hurricane season, and it’s very important that people understand that.”

The CSU team saw a 75 percent probability of a major hurricane making landfall along the U.S. coastline.

The 2010 Atlantic hurricane season has been predicted to be very active, with one private forecaster, Weather Services International (WSI), foreseeing 20 named storms, 11 hurricanes and five intense hurricanes of Category 3 or greater. This is significantly above the long-term average taken between 1950-2009 which shows 10 named storms, six hurricanes and two intense hurricanes.

In addition to the risk that major hurricanes can pose to about one-quarter of U.S. oil production and more than a tenth of natural gas output offshore in the Gulf of Mexico, this year’s storms threaten to complicate efforts to address the environmental disaster of BP’s blown-out oil well.

Although the ruptured Macondo seabed well was provisionally capped in mid-July, halting the leak of oil from it into the Gulf of Mexico, storms could still disrupt ongoing efforts to ”kill” the well with a permanent plug.

All of the major forecasters see a much more active season than last year’s season, which was one of the quietest in a decade with just nine tropical storms.

There have already been three named storms this season, Alex, Bonnie and Colin. Alex, the season’s first hurricane so far, drenched the Texas-Mexico border on April 1 as it made landfall as a Category 2 storm.

The season is just approaching its traditional busy phase, which runs from mid-August to October.

Read more: http://www.insurancejournal.com/news/national/2010/08/05/112214.htm#ixzz0vq1VrTzI

Across the entire Atlantic Basin for the six-month season, which begins June 1, NOAA (National Oceanic and Atmospheric Administration) is projecting a 70 percent probability of the following ranges:

14 to 23 named storms (top winds of 39 mph or higher), including:
8 to 14 hurricanes (top winds of 74 mph or higher), of which:
3 to 7 could be major hurricanes (category 3, 4 or 5; winds of at least 111 mph)
“If this outlook holds true, this season could be one of the more active on record,” said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. “The greater likelihood of storms brings an increased risk of a landfall. In short, we urge everyone to be prepared.”

The outlook ranges exceed the seasonal average of 11 named storms, six hurricanes and two major hurricanes.

According to NOAA, the expected factors supporting this outlook are:

Upper atmospheric winds conducive for storms. Wind shear, which can tear apart storms, will be weaker since El Niño in the eastern Pacific has dissipated. Strong wind shear helped suppress storm development during the 2009 hurricane season.

Warm Atlantic Ocean water. Sea surface temperatures are expected to remain above average where storms often develop and move across the Atlantic. Record warm temperatures – up to four degrees Fahrenheit above average – are now present in this region.

High activity era continues. Since 1995, the tropical multi-decadal signal has brought favorable ocean and atmospheric conditions in sync, leading to more active hurricane seasons. Eight of the last 15 seasons rank in the top ten for the most named storms with 2005 in first place with 28 named storms.

“The main uncertainty in this outlook is how much above normal the season will be. Whether or not we approach the high end of the predicted ranges depends partly on whether or not La Niña develops this summer,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “At present we are in a neutral state, but conditions are becoming increasingly favorable for La Niña to develop.”

FEMA Ready
Meanwhile, the Federal Emergency Management Agency is urging residents to prepare.

“FEMA is working across the administration and with our state and local partners to ensure we’re prepared for hurricane season,” said FEMA Administrator Craig Fugate. “But we can only be as prepared as the public, so it’s important that families and businesses in coastal communities take steps now to be ready. These include developing a communications plan, putting together a kit, and staying informed of the latest forecasts and local emergency plans. You can’t control when a hurricane or other emergency may happen, but you can make sure you’re ready.”

President Obama recently designated May 23 through 29 as National Hurricane Preparedness Week. NOAA and FEMA encourage those living in hurricane-prone states to use this time to review their overall preparedness. More information on individual and family preparedness can be found at http://www.Ready.gov and http://www.hurricanes.gov/prepare.

NOAA said its scientists will continue to monitor evolving conditions in the tropics and will issue an updated hurricane outlook in early August, just prior to what is historically the peak period for hurricane activity.

Read more: http://www.insurancejournal.com/news/national/2010/05/27/110239.htm#ixzz0pu54dqxt

Forecasters also said that at least three of the storms would move through the region currently affected by the Gulf of Mexico oil spill.

According to AccuWeather’s chief hurricane forecaster, Joe Bastardi, the U.S. will experience its worse storms during September. “Expect eight named storms in September and three or four U.S. impacts.”

Forecasters are predicting more activity in part because sea temperatures are higher than normal west of Africa, while activity related to El Nino, which can act to retard Atlantic hurricane activity, has declined.

The U.S. National Oceanographic and Atmospheric Administration (NOAA) is also predicting an active season, forecasting 14 to 23 named storms. The most active season on record occurred in 2005, when there were 28 named storms, including Hurricane Katrina.