Tag Archive for: 2023 Atlantic Hurricane Season

2023 Hurricane Season Ranked 4th in Named Storms

Adapted from NOAA Post: The above-normal 2023 Atlantic hurricane season officially ended on Nov. 30. It was characterized by record-warm Atlantic sea-surface temperatures, a strong El Niño, and the fourth highest number of named storms in a season.

NOAA’s GOES-16 satellite captured Hurricane Idalia approaching the western coast of Florida while Hurricane Franklin churned in the Atlantic Ocean at 5:01 p.m. EDT on August 29, 2023.  (Image credit: NOAA Satellites )

20 Named Storms, One of Which was Unnamed

The Atlantic basin saw 20 named storms in 2023. That ranks fourth for the most-named storms in a year since 1950. The unnamed-named storm was a tropical storm in January that was retroactively classified as a tropical storm.

Seven storms were hurricanes and three intensified to major hurricanes. An average season has 14 named storms, seven hurricanes and three major hurricanes. 

The Atlantic basin saw 20 named storms in 2023, ranking 4th for most-named storms in a year. Tropical cyclone names are selected by the World Meteorological Organization. (Image credit: NOAA)

Only One U.S. Landfalling Hurricane

Hurricane Idalia was the only U.S. landfalling hurricane in 2023. It made landfall as a category-3 hurricane on Aug. 30 near Keaton Beach, Florida, causing storm surge inundation of 7 to 12 feet and widespread rainfall flooding in Florida and throughout the southeast. 

Tropical Storm Ophelia made landfall as a strong tropical storm with 70 mph winds on Emerald Isle, North Carolina, on Sept. 23 causing widespread heavy rainfall, gusty winds and significant river and storm surge flooding in portions of eastern North Carolina. 

Hurricane Lee made landfall as a post-tropical cyclone in Nova Scotia, Canada, on Sept. 16. Swells generated by Lee caused dangerous surf and rip currents along the entire U.S. Atlantic coast. Strong winds with hurricane‑force gusts from Lee caused extensive power outages in Maine and in parts of Canada.

Season Fell within Predicted Range

The 2023 Atlantic seasonal activity fell within the NOAA Climate Prediction Center’s predicted ranges for named storms and hurricanes in the August updated outlook.

“The Atlantic basin produced the most named storms of any El Nino influenced year in the modern record,” said Matthew Rosencrans, lead hurricane forecaster at NOAA’s Climate Prediction Center — a division of NOAA’s National Weather Service. “The record-warm ocean temperatures in the Atlantic provided a strong counterbalance to the traditional El Nino impacts.”

Eastern Pacific Also Above Normal, but Within Predicted Range

The eastern Pacific basin hurricane season was also above normal with 17 named storms, of which 10 were hurricanes and eight of those major hurricanes. From Aug. 16 to 21, Tropical Storm Hilary brought widespread heavy rainfall and flooding to Southern California, with some areas receiving up to 600% of their normal August rainfall. Hilary resulted in the first ever issuance of Tropical Storm Watches and Warnings for the Southern California coastline by NOAA’s National Hurricane Center. In addition, the Center distributed key hazard focused messages for Hilary in Spanish through the agency’s new language translation project

Hurricane Otis made landfall near Acapulco, Mexico, on Oct. 25 as a category-5 hurricane with sustained winds of 165 mph. Otis holds the record as the strongest landfalling hurricane in the eastern Pacific after undergoing rapid intensification in which wind speeds increased by 115 mph in 24 hours.

The central Pacific basin had a near-normal season with four tropical systems traversing the basin. Hurricane Dora, a category-4 storm, passed south of Hawaii in early August, marking the first major hurricane in the central Pacific basin since 2020. The strong gradient between a high pressure system to the north and Dora to the south was a contributing factor to the wind-driven, fast-moving wildfires in Hawaii.

Hurricane season activity for the eastern Pacific and central Pacific fell within predicted ranges.

Hazards Felt Well Inland Underscores Need for Planning

“Another active hurricane season comes to a close where hazards from the storms extended well inland from the landfall location,” said NOAA National Hurricane Center Director Michael Brennan, Ph.D.  “This underscores the importance of having a plan to stay safe whether you’re at the coast or inland.” 

New System Improved Intensity Predictions, Response Times

NOAA’s new Hurricane Analysis and Forecast System helped National Hurricane Center forecasters improve intensity predictions this season. NOAA’s intensity forecasts showed Hurricane Idalia as a major hurricane impacting the coast of Florida as early as Aug. 28.

This lead time gave those in threatened areas more time to prepare and respond, and there were no storm surge fatalities from Idalia despite storm surge inundation of as much as 12 feet above ground level in some areas. Further, extending the National Hurricane Center’s tropical weather outlook product from five to seven days, this season provided emergency managers more time to prepare and stage resources before a storm.

NOAA’s Hurricane Research and Response

This season, NOAA Hurricane Hunter aircraft flew 468 mission hours to collect atmospheric data that is critical to hurricane forecasting and research, passing through the eye of a hurricane 120 times and deploying over 1,400 scientific instruments. Since 2020 through this 2023 season, NOAA’s two Lockheed WP-3D Orion have flown 40% more hurricane mission flights than the preceding four years (2016-2019). 

NOAA celebrated the first operational launch of a Black Swift drone from a NOAA WP-3D Orion to gather atmospheric data in and around Hurricane Tammy. Further, the first successful coordination of a low-flying drone (Anduril’s Altius 600), atmospheric profilers (dropsondes), and ocean profilers (bathythermographs) also launched from a NOAA WP-3D Orion.

Observations and information from these deployments are being evaluated to determine the feasibility of using the data to help with hurricane forecasting in the future. 

NOAA’s Beechcraft King Air flew 28 mission hours to collect aerial imagery used for emergency response after Hurricanes Idalia and Lee. Following Hurricane Idalia, NOAA’s National Ocean Service provided support to enable safe maritime navigation, gathering survey data for 36.8 linear nautical miles and identifying 29 potential obstructions along Florida’s coastal waterways.

NOAA also worked to identify hazards caused by capsized vessels, damaged docks and piers, parts of homes and other types of marine debris, and shared findings with Florida’s debris task force following Hurricane Idalia.  

New Use of Weather Satellites

NOAA’s geostationary and polar-orbiting weather satellites provided vital information for monitoring and forecasting the hurricanes and tropical weather that threatened our lives and property this season. Forecasters used one-minute geostationary satellite imagery to assess structure changes during the rapid intensity of storms such as Idalia, Lee and Otis. 

NOAA’s polar-orbiting satellites orbit the Earth from pole to pole 14 times a day, providing full global coverage twice daily. Throughout the hurricane season, these satellites made sophisticated and precise observations of the atmosphere, ocean and land, which were critical to developing daily and 3-5 day forecasts.

Timing for Next Year’s Forecast and Official 2023 Report

The National Hurricane Center and Central Pacific Hurricane Center Tropical Cyclone Reports for 2023, including synoptic history, meteorological statistics, casualties and damages, and the post-analysis best track, will be published on the 2023 Tropical Cyclone Report site in March 2024. 

NOAA’s Climate Prediction Center, a division of the National Weather Service, will issue its 2024 hurricane seasonal outlook in May 2024. The hurricane season officially begins on June 1. 

Adapted from NOAA Story by Bob Rehak

2290 Days since Hurricane Harvey

NOAA Increases 2023 Atlantic Hurricane Season Forecast

Reprinted from the National Hurricane Center website with some additions.

Scientists at NOAA’s Climate Prediction Center — a division of the National Weather Service — have increased their prediction for the ongoing 2023 Atlantic hurricane season from a near-normal level of activity to an above-normal level of activity.

Forecasters believe that current ocean and atmospheric conditions, such as record-warm Atlantic sea surface temperatures, are likely to counterbalance the usually limiting atmospheric conditions associated with the ongoing El Nino event.

Chances of Above Normal Season Increase from 30% to 60%

NOAA forecasters have increased the likelihood of an above-normal Atlantic hurricane season to 60% (increased from the outlook issued in May, which predicted a 30% chance). The likelihood of near-normal activity has decreased to 25%, down from the 40% chances outlined in May’s outlook. This new update gives the Atlantic a 15% chance of seeing a below-normal season. 

Prediction for Named Storms Increase from 12-17 to 14-21

In May 2023, NOAA predicted 12-17 named storms. NOAA’s update calls for 14-21 named storms (winds of 39 mph or greater). Of those, 6-11 could become hurricanes (winds of 74 mph or greater). And of those, 2-5 could become major hurricanes (winds of 111 mph or greater).

NOAA provides these ranges with a 70% confidence. These updated ranges include storms that have already formed this season.

2023 Atlantic Hurricane Season Forecast
The updated 2023 Atlantic hurricane season probability and number of named storms. (Image credit: NOAA)

The Atlantic basin experienced an active start to the hurricane season with five storms that have reached at least tropical storm strength, including one hurricane already. An average hurricane season produces 14 named storms, of which seven become hurricanes, including three major hurricanes.

Climate Factors Influencing Predictions

“The main climate factors expected to influence the 2023 Atlantic hurricane activity are the ongoing El Nino and the warm phase of the Atlantic Multi-Decadal Oscillation, including record-warm Atlantic sea surface temperatures,” said Matthew Rosencrans, lead hurricane season forecaster with NOAA’s Climate Prediction Center.

Sea surface temperature departures from normal for August 10, 2023. Source: NOAA

Considering those factors, the updated outlook calls for more activity, so NOAA urges everyone to prepare now for the continuing season.

Activity should ramp up quickly in August and September, if this season follows the pattern for the last 100 years.

El Nino conditions are currently being observed and there is a greater than 95% chance that El Nino will continue through the Northern Hemisphere winter, according to the latest ENSO discussion from the Climate Prediction Center.

El Nino usually results in atmospheric conditions that help to lessen tropical activity during the Atlantic hurricane season. So far, those limiting conditions have been slow to develop.

Climate scientists forecast that the El-Nino associated impacts that limit tropical cyclone activity may not be in place for much of the remaining hurricane season.

NOAA’s Climate Prediction Center

A below-normal wind shear forecast, slightly below-normal Atlantic trade winds and a near- or above-normal West African Monsoon were also key factors in shaping this updated seasonal forecast.

Five Storms Already

The Atlantic basin experienced a tropical storm in January which was unnamed. Since the start of the season, we have already experienced four other storms.

2023 Atlantic Hurricane Season Names
The 2023 Atlantic tropical cyclone names selected by the World Meteorological Organization. (Image credit: NOAA)

More About Hurricane Season Outlooks

NOAA’s hurricane outlooks are forecasts of overall season activity, not landfalls. A storm’s landfall is usually the result of mesoscale weather patterns and are typically predictable within roughly one week of a storm approaching a landmass. 

In June, NOAA deployed a new model to help produce hurricane forecasts. The Hurricane Analysis and Forecast System was put into operations on June 27 and will run alongside existing models for the 2023 season before replacing them as NOAA’s premier hurricane forecasting model.

NOAA urges everyone in vulnerable areas to have a well-thought-out hurricane plan and stay informed through official channels as this season progresses. 

I bookmark the National Hurricane Center landing page and check it first thing every morning during the season. NHC expects no tropical activity in the Atlantic during the next seven days.

Reposted by Bob Rehak on 8/11/2023 from the National Hurricane Center

2073 Days since Hurricane Harvey