Aug. 29 – NASA Sees Post-Tropical Cyclone Lane Come to an End
The once hurricane that dropped record-setting rainfall on the Hawaiian Islands has come to an end in the Central Pacific Ocean and NASA-NOAA’s Suomi NPP satellite captured a visible image of its final hours.
NASA-NOAA’s Suomi NPP satellite flew over Post-Tropical Cyclone Lane on Aug. 28 at 7:54 p.m. EDT (2354 UTC).The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA’s Suomi NPP satellite provided a visible image that showed wind shear has taken its toll on the storm and pushed all of the clouds northeast of the cloud-less center of circulation.
The final warning came from NOAA’s Central Pacific Hurricane Center at 0300 UTC on Aug. 29 (11 p.m. EDT on Aug. 28) when Lane’s center was located near 19.5 degrees north latitude and 168.3 degrees west longitude. That’s 330 miles south-southwest of French Frigate Shoals, Hawaii. At the time, maximum sustained winds were near 28.7 mph (25 knots/46.3 kph).
Lane has ceased to be a tropical cyclone and will dissipate soon.
By Rob Gutro
NASA’s Goddard Space Flight Center
Aug. 28 – NASA Looks at Fluctuating Strength of Tropical Storm Lane
When NASA’s Aqua satellite passed over tropical cyclone Lane on Aug. 27 it had just regained tropical storm status and showed powerful thunderstorms around east of its center of circulation. However, wind shear kicked back up and by 11 p.m. EDT that day, Lane had again weakened back to tropical depression status.
NASA’s Aqua satellite passed over Lane on Aug. 27 at 8:17 a.m. EDT (1217 UTC). The Atmospheric Infrared Sounder or AIRS instrument analyzed the storm in infrared light which provides temperature information. Temperature is important when trying to understand how strong storms can be. The higher the cloud tops, the colder and the stronger they are.
AIRS saw coldest cloud top temperatures being pushed east of center by strong vertical wind shear. Those cloud top temperatures were as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius). Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.
On Aug. 28, NOAA’s Central Pacific Hurricane Center or CPHC noted that there were no coastal watches or warnings in effect. However, CPHC cautioned that interests in the Northwestern Hawaiian Islands should continue to monitor the progress of Lane.
Infrared data on Aug. 28 showed only small, scattered and short-lived puffs of deep convection in the northern semicircle. CPHC said those were located from 50 nautical miles northwest to over 100 nautical miles northeast and east of the center.
The University of Wisconsin- Cooperative Institute for Meteorological Satellite Studies or UW-CIMSS diagnosed vertical wind shear of over 69 mph (60 knots/111 kph) were affecting Tropical Depression Lane. Those winds are ripping away the cloud tops of strong storms near the low-level center and pushing them to the northeast.
At 5 a.m. EDT (0900 UTC) on Aug. 28 (11 p.m. HST, Aug. 27) the center of Tropical Depression Lane was located near latitude 18.4 degrees north and longitude 167.4 degrees west. The depression is moving toward the west near 7 mph (11 kph). Lane is forecast to move to the north-northwest. Maximum sustained winds were near 35 mph (55 kph) with higher gusts. Slight weakening is forecast during the next 48 hours.
Lane is forecast to become a remnant low pressure area later in the day. The remnant low is then expected to dissipate on Wednesday, Aug. 29 as it becomes absorbed into a developing extratropical low farther to the north.
For updated forecasts, visit the Central Pacific Hurricane Center website: http://www.prh.noaa.gov/cphc/
By Rob Gutro
NASA’s Goddard Space Flight Center
Aug. 27, 2018 – NASA Finds Wind Shear Slamming Tropical Cyclone Lane
Infrared satellite imagery shows scientists where the coldest cloud tops are located in a tropical cyclone and can give a clear picture of wind shear’s effects. NASA’s Aqua satellite data showed wind shear was pushing Tropical Depression Lane’s strongest storms east of its center. Despite the wind shear, Lane strengthened back into a tropical storm on Aug. 27.
On Monday, August 27, 2018 there were no coastal watches or warnings in effect. However, NOAA’s Central Pacific Hurricane Center or CPHC said that interests in the Northwestern Hawaiian Islands should continue to monitor the progress of Lane.
At 8:15 a.m. EDT (1215 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard Aqua measured cloud top temperatures in Lane when it was a depression. Coldest cloud tops were near minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius), east of the center. Those storms were being pushed there by strong westerly winds. Storms with cloud top temperatures that cold have the capability to produce heavy rainfall.
Fortunately, that heavy rain is falling over open ocean waters. The infrared imagery showed that those strong storms were not reaching the Hawaiian Islands.
By 11 a.m. EDT (5 a.m. HST/1500 UTC), NOAA’s CPHC said that Lane regained strength and was upgraded from a tropical depression to a tropical storm. At that time the center of Tropical Storm Lane was located near latitude 18.9 degrees north and longitude 165.5 degrees west. That’s about 520 miles (835 km) west-southwest of Honolulu, Hawaii.
Lane is moving toward the west near 8 mph (13 km/h), and this motion is expected to continue today. A decrease in forward speed is expected tonight as Lane makes a turn toward the northwest. Lane is then expected to accelerate toward the northwest on Tuesday, Aug. 28 and Wednesday, Aug. 29.
Maximum sustained winds are near 40 mph (65 kph) with higher gusts. Some short-term weakening is forecast, and Lane is expected to become a post-tropical remnant low by Tuesday. Lane may strengthen as an extratropical low as it passes over portions of the Northwestern Hawaiian Islands from Tuesday night through Thursday, Aug. 30.
For updated forecasts from the CPHC, visit: http://www.prh.noaa.gov/cphc
By Rob Gutro
NASA’s Goddard Space Flight Center,
Aug. 26, 2018 – Former Hurricane Lane Weakened to a Depression
Tropical Depression Lane continues to weaken and move away from Hawaii. Satellite imagery showed a much more disorganized system with light to moderate rainfall.
A satellite image that combines infrared data from NOAA’s GOES-West satellite to show clouds with rainfall data from NASA/JAXA’s GPM satellite. The image provided a full picture of the depression and showed light rain was falling over the Hawaiian Islands on Aug. 26 at 1516 UTC (11: 16 a.m. EDT).
Lingering moisture associated with Lane will produce heavy rainfall over portions of the main Hawaiian Islands today, Aug. 26, which could lead to additional flash flooding and landslides.
On Aug. 26, there were no coastal watches or warnings in effect. NOAA’s Central Pacific Hurricane Center or CPHC noted that interests in the Northwestern Hawaiian Islands should continue to monitor the progress of Lane.
At 11 a.m. EDT (5 a.m. HST/1500 UTC), the center of Tropical Depression Lane was located near latitude 19.1 North, longitude 162.2 West. The depression is moving toward the west near 10 mph (17 km/h), and this general motion is expected to continue into Monday, Aug. 27. A brief slowing in forward motion is expected Monday night as Lane makes a turn toward the northwest. Lane is then expected to accelerate northwestward by Tuesday as it transitions to an extratropical low.
Maximum sustained winds are near 35 mph (55 kph) with higher gusts. Some weakening is forecast during the next 48 hours, and Lane is expected to become a post-tropical remnant low later today or tonight. In a couple of days, Lane may develop into a gale force extratropical low as it passes over portions of the Northwestern Hawaiian Islands.
For updated forecasts, visit: http://www.prh.noaa.gov/cphc
By Rob Gutro
NASA’s Goddard Space Flight Center
Aug. 25, 2018 – Lane’s Hawaii Soaking Continues as NASA Analyzes the Tropical Storm
By Aug. 25, Hurricane Lane had weakened to a tropical storm. Despite the drop in strength, the heavy rains persist over the Hawaiian Islands. NASA’s Aqua and GPM satellites provided a look at the location of Lane and the rainfall rates. NOAA’s Central Pacific Hurricane Center or CPHC said at 8 a.m. EDT (2 a.m. HST) today, Saturday, August 25, 2018, “Lane’s outer rain bands producing severe flooding across parts of the Hawaiian Islands.”
A Tropical Storm Warning is in effect for Oahu, Maui County…including the islands of Maui, Lanai, Molokai and Kahoolawe and Hawaii County A Tropical Storm Watch is in effect for Kauai County…including the islands of Kauai and Niihau.
On Aug. 25, The MODIS instrument aboard NASA’s Aqua satellite showed that Lane was centered west of the Big Island (Island of Hawaii), while a band of thunderstorms stretched east bringing more drenching rainfall over the Island of Hawaii.
NASA and the Japan Aerospace Exploration Agency’s Global Precipitation Measurement mission or GPM satellite measured rainfall rates at 12:46 a.m. EDT (0446 UTC) and found the southwestern tip of the Island of Hawaii and the west coast were receiving rainfall at a rate over 1.2 inches per hour. The GPM was coupled with an infrared image from NOAA’s GOES-West satellite to show the clouds of the tropical storm and form and entire picture.
NOAA’s CPHC said “Lane’s outer rain bands will produce excessive rainfall this weekend, which could lead to additional flash flooding and landslides. Lane is expected to produce total rain accumulations of 10 to 20 inches in some areas. Localized storm total amounts well in excess of 40 inches have already been observed along the windward side of the Big Island.”
At 6 a.m. EDT (2 a.m. HST/1200 UTC), the center of Tropical Storm Lane was located near latitude 19.5 degrees north and longitude 158.4 degrees west. Maximum sustained winds are near 65 mph (100 kph) with higher gusts. Additional weakening is forecast through Sunday night. Tropical-storm-force winds extend outward up to 130 miles (215 km) from the center.
Lane is moving toward the north-northwest near 3 mph (6 kph), and this general motion is expected to continue through this morning. This will likely be followed by a turn toward the west with an increase in forward speed starting later today or tonight. This westward motion is forecast to continue through Sunday. On the forecast track, the center of Lane will pass south of Kauai and Niihau later today.
The CPHC forecast noted that Tropical storm conditions are still expected in and near outer rain bands that will affect Oahu, Maui County and the Big Island today. Tropical storm conditions are possible on Kauai starting later today. Large swells generated by Lane will impact the Hawaiian Islands. These swells will produce high surf along exposed south and east shorelines through this morning. Isolated tornados are possible through this morning across parts of the Big Island, Maui County and Oahu.
For updated forecasts, visit: http://www.prh.noaa.gov/cphc
By Rob Gutro
NASA’s Goddard Space Flight Center
Aug. 24, 2018 (#2) – Multiple NASA Instruments Capture Hurricane Lane
Instruments on NASA’s Terra and Aqua satellites were watching as Hurricane Lane — a category 2 storm as of Friday, Aug. 24 — made its way toward Hawaii.
NASA’s Multi-angle Imaging SpectroRadiometer (MISR) captured images of Lane on just before noon local time on Aug. 24. MISR, flying onboard NASA’s Terra satellite, carries nine cameras that observe Earth at different angles. It takes approximately seven minutes for all the cameras to observe the same location, and the motion of the clouds during that time is used to compute the wind speed at the cloudtops.
The image shows the storm as viewed by the central, downward-looking camera. Also included is a stereo anaglyph, which combines two of the MISR angles to show a three-dimensional view of Lane. The image has been rotated in such a way that north is at the bottom. You will need red-blue glasses to view the anaglyph (with the red lens placed over your left eye).
MISR was built and is managed by NASA’s Jet Propulsion Laboratory in Pasadena, California, for NASA’s Science Mission Directorate in Washington. JPL is a division of Caltech. The Terra spacecraft is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. The MISR data were obtained from the NASA Langley Research Center Atmospheric Science Data Center in Hampton, Virginia.
NASA’s Atmospheric Infrared Sounder (AIRS) captured Hurricane Lane when the Aqua satellite passed overhead on Aug. 22 and 23. The infrared imagery represents the temperatures of cloud tops and the ocean surface. Purple shows very cold clouds high in the atmosphere above the center of the hurricane, while blue and green show the warmer temperatures of lower clouds surrounding the storm center. The orange and red areas, away from the storm, have almost no clouds, and the ocean shines through. In the Aug. 22 image, a prominent eye is also visible. No eye is visible on the Aug. 23 image, either because it was too small for AIRS to detect or it was covered by high, cold clouds.
AIRS, in conjunction with the Advanced Microwave Sounding Unit (AMSU) senses emitted infrared and microwave radiation from Earth to provide a three-dimensional look at Earth’s weather and climate. Working in tandem, the two instruments make simultaneous observations all the way down to Earth’s surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, three-dimensional map of atmospheric temperature and humidity, cloud amounts and heights, greenhouse gas concentrations, and many other atmospheric phenomena. Launched into Earth orbit in 2002, the AIRS and AMSU instruments fly onboard NASA’s Aqua spacecraft and are managed by JPL.
More information about MISR is available at these sites: https://www-misr.jpl.nasa.gov/
https://eosweb.larc.nasa.gov/project/misr/misr_table
More information about AIRS is at: https://airs.jpl.nasa.gov/
Esprit Smith
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-4269
esprit.smith@jpl.nasa.gov
Aug. 24, 2018 (#1) – NASA Looks at Heavy Rainmaker in Hurricane Lane
Cloud top temperatures provide scientists with an understanding of the power of a tropical cyclone. NASA’s Aqua satellite observed Hurricane Lane in infrared light to those temperatures.
The higher the cloud tops, the colder and the stronger they are. So infrared light as that gathered by the MODIS instrument can identify the strongest sides of a tropical cyclone. Wherever cloud top temperatures are as cold as or colder than minus 63 degrees Fahrenheit (minus 53 degrees Celsius), those storms have the potential to drop heavy rain.
Hurricane Lane’s cloud top temperatures were colder than that, meaning that the storm has a potential to drop even heavier rainfall. Rainfall is the biggest threat from Lane.
On Aug. 23 at 7:35 p.m. EDT (2335 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Aqua satellite found the coldest temperatures of the strongest thunderstorms in Hurricane Lane were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius) north of the center. They were embedded in a large area of storms that circled the eye where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius).
Rainfall Expected
On Aug. 24, NOAA’s Central Pacific Hurricane Center or CPHC noted that catastrophic flooding occurring on the big island of Hawaii. CPHC said “Rain bands will continue to overspread the Hawaiian Islands well ahead of Lane. Excessive rainfall associated with this slow moving hurricane will continue to impact the Hawaiian Islands into the weekend, leading to catastrophic and life-threatening flash flooding and landslides. Lane is expected to produce total rain accumulations of 10 to 20 inches, with localized amounts up to 40 inches possible over portions of the Hawaiian Islands. Over 30 inches of rain has already fallen at a couple locations on the windward side of the Big Island.”
The slow movement of Lane also greatly increases the threat for prolonged heavy rainfall and extreme rainfall totals. This is expected to lead to major, life-threatening flash flooding and landslides over all Hawaiian Islands.
Warnings and Watches
A Hurricane Warning is in effect for Oahu, Maui County…including the islands of Maui, Lanai, Molokai and Kahoolawe. A Tropical Storm Warning is in effect for Hawaii County.
A Hurricane Watch is in effect for Kauai County…including the islands of Kauai and Niihau.
Key Messages and Cautions from NOAA’s CPHC
Lane will pass dangerously close to the main Hawaiian Islands as a hurricane on Friday, and is expected to bring damaging winds. The slow movement of Lane also greatly increases the threat for prolonged heavy rainfall and extreme rainfall totals. Large and damaging surf can be expected along exposed shorelines, especially along south and west facing coasts, with localized storm surge exacerbating the impacts of a prolonged period of damaging surf.
Although the official forecast does not explicitly indicate Lane’s center making landfall over any of the islands, this remains a very real possibility. Even if the center of Lane remains offshore, severe impacts could still be realized as they extend well away from the center.
Wind Shear Affecting Lane
CPHC said, “Hurricane Lane is beginning to show some signs of slow weakening due to wind shear of over 20 knots from the southwest according to the SHIPS and UW-CIMSS analyses. There is no eye evident in satellite imagery, which is likely a result of these hostile conditions.”
Lane’s Location on Aug. 24
At 11 a.m. EDT (5 a.m. HST/1500 UTC), the center of Hurricane Lane was located near latitude 18.7 degrees north and longitude 158.0 degrees west.
Lane is moving toward the north near 5 mph (7 kph), and this general motion is expected to continue through tonight. A turn toward the west is anticipated on Saturday, with an increase in forward speed. On the latest forecast track, the center of Lane will move dangerously close to portions of the central Hawaiian Islands later today, Aug. 24 and tonight.
Maximum sustained winds are near 110 mph (175 kph) with higher gusts. Lane is now Category 2 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some additional weakening is forecast later today and tonight, but Lane is expected to remain a dangerous hurricane as it approaches the islands. Further weakening is expected on Saturday, Aug.25. The estimated minimum central pressure is 962 millibars.
For updated forecasts, visit: http://www.prh.noaa.gov/cphc
By Rob Gutro
NASA’s Goddard Space Flight Center
Aug. 23, 2018 – NASA Analyzes a Solid Ring of Cold Cloud Tops Hurricane Lane
An infrared look by NASA’s Terra satellite provided forecasters with temperature data in the Category 4 hurricane near Hawaii. Terra data showed a large ring of coldest and most powerful storms around Hurricane Lane’s eye on Aug. 23.
NOAA’s Central Pacific Hurricane Center or CPHC noted that a Hurricane Warning is in effect for Oahu, Maui County including the islands of Maui, Lanai, Molokai and Kahoolawe and Hawaii County. A Hurricane Watch is in effect for Kauai County, including the islands of Kauai and Niiha.
On Aug. 23 at 4:15 a.m. EDT (0815 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA’s Terra satellite analyzed cloud top temperatures in infrared light. MODIS found cloud top temperatures of the strongest thunderstorms northeast and southwest of the eye were as cold as or colder than minus 80 degrees Fahrenheit (minus 62.2 Celsius). They were embedded in a large area or storms that circled the eye where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius).
Cloud top temperatures that cold indicate strong storms that have the capability to create heavy rain. Rainfall is expected to be the biggest threat from Lane.
CPHC said, “The cloud-filled eye continues to be surrounded by a solid ring of cold cloud tops, with lightning bursts persisting in the northern eye wall for the last several hours.”
CPHC also noted, “Excessive rainfall associated with Lane will impact the Hawaiian Islands into the weekend, leading to significant and life-threatening flash flooding and landslides. Lane is expected to produce total rain accumulations of 10 to 20 inches, with localized amounts in excess of 30 inches over the Hawaiian Islands.”
At 8 a.m. EDT (2 a.m. HST/1200 UTC) on Aug. 23, the eye of Hurricane Lane was located by satellite and radar near latitude 16.5 degrees north and longitude 157.3 degrees west.
NOAA’s CPHC said, “Lane is moving toward the northwest near 7 mph (11 kph). This general motion is expected to continue today, with a gradual turn toward the north-northwest. On Friday, a turn toward the north is anticipated as Lane’s forward motion slows even more. A turn back toward the west is expected on Saturday. On the forecast track, the center of Lane will move very close to or over the main Hawaiian Islands later today through Friday (Aug. 24).”
Maximum sustained winds are near 130 mph (215 kph) with higher gusts. Hurricane-force winds extend outward up to 40 miles (65 km) from the center and tropical-storm-force winds extend outward up to 140 miles (220 km).
Lane is a powerful category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.
CPHC said, “Some weakening is forecast during the next day or so, with more significant weakening thereafter. Lane is expected to remain a hurricane as it approaches the islands.”
For updated forecasts, visit: http://www.prh.noaa.gov/cphc
By Rob Gutro
NASA’s Goddard Space Flight Center
For earlier information on Lane go to: https://www.nasa.gov/feature/goddard/2018/lane/