Remainder of the hurricane season may be more active

The Atlantic and Caribbean tropical storm and hurricane season began on June 1 and we’ve seen nine named storms as of Sunday. The normal amount for an entire season ending on Nov. 30 is 11.

In May, the National Oceanic and Atmospheric Administration (NOAA) predicted 10 to 16 named storms, with five to nine of them to become hurricanes. They also estimated that one to four of those hurricanes would become major. Recently, NOAA updated its prediction to 15 named storms with seven of them to become hurricanes. They also foresee that three of the hurricanes expected to form will become major before the season ends later this year.

For the 2018 season, many scientists have claimed that conditions through early September were relatively quiet. However, Florence became the fourth hurricane of the season and is forecast to become a major Category 4 storm later this week, threatening the eastern coastlines from Georgia to Washington D.C. As of early Sunday, tropical storms Helene and Isaac were also forming in the Atlantic Ocean.

Earlier this month, Tropical Storm Gordon made landfall just west of the Alabama-Mississippi border and dumped heavy rainfall. The storm’s peak intensity had maximum sustained winds of 70 mph. To be a Category 1 hurricane, sustained winds must be at 74 mph or above.

To be classified as a Category 5 hurricane, “sustained” winds must be at least 156 mph. Since 1851, there have been 32 hurricanes that reached Category 5 status. Amazingly enough, there only three of these hurricanes made landfall in the U.S. as a Category 5. In 2005, Katrina weakened to a Category 3 when it hit New Orleans.

The 2017 Atlantic hurricane season was a very destructive year. There were 17 named storms and 6 major hurricanes. It was the fifth-most active season since records began in 1851. Last year also had the highest number of hurricanes since 2005.

Last year was also the costliest tropical cyclone season on record with a price tag of $282.22 billion. That figure accounted for about 25 percent of all the combined natural disasters in the United States from 1980 until 2017. That didn’t include the major wildfires in the West — plus all the floods and droughts across the rest of the country.

A new study from the National Oceanic and Atmospheric Administration, claims that inactive hurricane seasons may have storms that have rapid intensifications, mainly in the Gulf of Mexico. Wind shear often prohibits the development of major hurricanes, especially during El Nino years. NOAA says that seasons with less storms typically have lower wind shears over the Gulf of Mexico, resulting in the intensifications. They also said that more active tropical storm and hurricane seasons would have more storms, but less of them get close to the U.S. coastlines.

Cliff and I have not changed our original prediction, as we believe that the rest of this season may have an above-average number of tropical storms or hurricanes. We see approximately 15-18 named storms with 6-8 of them becoming hurricanes. Four of these potentially deadly storms are expected to become major hurricanes, reaching at least Category 3 status.

The Far West continues to be dominated by a strong ridge of high pressure. The extended period of heat and dryness has sparked more wildfires in California, including a second blaze near Redding. This year, more than 1.2 million acres have burned in the Golden State, destroying over 1,200 homes. Last year, 1.4 million acres were charred. And, California’s fire season will likely extend well into the fall season.

According to the National Interagency Fire Center, computer models that are used to predict fire activity suggest that blazes would likely be more difficult to contain and will go more rapidly over the next several months. Over the summer, California saw some of the largest wildfires in history.

In terms of our local weather, Cliff tells me that if Coeur d’Alene didn’t get the rainfall from the storm in late August that dropped approximately .60 inches of moisture, the summer of 2018 would have likely finished in the top 3 for the hottest and driest since records began in 1895.

There is a chance of scattered rain showers this week from a series of weak Pacific storms. Then it will turn mostly dry, with more rain expected around the “full moon” cycle of Sept. 24. The normal precipitation for this month is 1.48 inches.

October and November’s precipitation total should turn to above-normal levels as more Pacific storms are expected to move into the region. October’s normal precipitation is 2.22 inches and November’s average moisture total is 3.07 inches. Snowfall totals may be below average in November if the warmer El Nino sea-surface temperature event forms in the waters of the south-central Pacific Ocean.

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Contact Randy Mann at randy@longrangeweather.com.