Florence produces record rainfall in North Carolina and South Carolina

September 17th, 2018 |

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images, with hourly precipitation type symbols plotted in yellow and SPC storm reports plotted in cyan, 13-17 September [click to play MP4 animation]

After Hurricane Florence made landfall in North Carolina during the morning hours on 14 September, it moved very slowly (at times only 2-3 mph) southwestward into South Carolina during 15-16 September (surface analyses). Prolonged heavy rainfall resulted (WPC summary), with new state records (see below) for precipitation from a tropical cyclone being set in North Carolina (35.93 inches) and South Carolina (23.63 inches). GOES-16 (GOES-East) “Clean” Infrared Window (10.3 µm) images every 5 minutes during the 4-day period of 13-16 September (above) showed the evolution of banding and the development of new convection that produced the heavy rainfall — widespread flooding along with strong winds caused power outages across portions of the 2 states (NC | SC), and closed sections of Interstates 95 and 40. Note that the power outages caused extended dropouts of the plotted surface reports — especially in eastern North Carolina; reports were missing when the gray 4-letter station identifiers disappeared — even though many of those sites were likely experiencing heavy rainfall during those dropout times.

Florence also spawned a few tornadoes on 14, 15 and 16 September — SPC storm reports are plotted in cyan on the GOES-16 Infrared images.

Hourly images of the MIMIC Total Precipitable Water product (below) showed tropical moisture associated with Florence as it moved inland during the 13-17 September period.

MIMIC Total Precipitable Water product [click to play animation | MP4]

MIMIC Total Precipitable Water product, 13-17 September [click to play animation | MP4]

Animations of plots of rawinsonde data from the coastal sites of Newport/Morehead City, North Carolina and Charleston, South Carolina (below) revealed the increase in deep tropical moisture from 13-16 September — Total Precipitable Water values were as high as 68.6 mm (2.70 inches) at Newport and 67.8 mm (2.67 inches) at Charleston.

Daily plots of rawinsonde data from Newport/Morehead City, North Carolina [click to enlarge]

Daily plots of rawinsonde data from Newport/Morehead City, North Carolina [click to enlarge]

Daily plots of rawinsonde data from Charleston, South Carolina [click to enlarge]

Daily plots of rawinsonde data from Charleston, South Carolina [click to enlarge]

As the remnants of Florence moved from Kentucky to West Virginia during the daylight hours of 17 September, numerous tornadoes occurred in central Virginia (SPC storm reports | NWS Wakefield summary). 1-minute GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (below) showed the development of thunderstorms which produced these tornadoes.

GOES-16 "Red" Visible (0.64 µm, left) and "Clean" Infrared Window (10.3 µm, right) images, with plots of SPC storm reports [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm, left) and “Clean” Infrared Window (10.3 µm, right) images, with plots of SPC storm reports [click to play MP4 animation]

 

===== 18 September Update =====

Before/after (26 August/18 September) Terra MODIS False Color RGB images [click to enlarge]

Terra MODIS False Color RGB images, 26 August vs. 18 September [click to enlarge]

A comparison of before/after (26 August/18 September) Terra MODIS False Color Red-Green-Blue (RGB) images from the MODIS Today site (above) showed areas of inland flooding (increasing water coverage appears as darker shades of blue) in the wake of Florence across far southeastern North Carolina and far northeastern South Carolina.

Looking slightly to the south, a similar before/after comparison of Terra MODIS True Color RGB images (below) revealed areas of sediment runoff into the Atlantic Ocean.

Terra MODIS True Color RGB images, 26 August vs. 18 September [click to enlarge]

Terra MODIS True Color RGB images, 26 August vs. 18 September [click to enlarge]

Hurricane Florence makes landfall in North Carolina

September 14th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface wind gusts in knots [click to play MP4 animation]

Hurricane Florence made landfall near Wrightsville Beach, North Carolina at 1115 UTC (7:15 am EDT) with estimated maximum winds of 78 knots (90 mph) and a minimum central pressure estimate of 958 hPa (28.29″). Overlapping GOES-16 (GOES-East) Mesoscale Domain Sectors provided images every 30 seconds — “Red” Visible (0.64 µm) images (above) and “Clean” Infrared Window (10.3 µm) images (below) showed the storm as it slowly moved inland after sunrise. A peak wind gust of 105 mph was recorded at Wilmington NC (which is located at the center of the GOES-16 images); in northeastern North Carolina, winds gusted to 105 mph at Fort Macon and 112 mph at the New River Inlet Buoy.

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images, with hourly plots of wind gusts [click to play MP4 animation]

The MIMIC Total Precipitable Water product (below) showed abundant moisture associated with Florence moving inland during the 48-hour period ending at 23 UTC on 14 September.

MIMIC Total Precipitable Water product [click to play animation | MP4]

MIMIC Total Precipitable Water product [click to play animation | MP4]

Toggles between Visible and Infrared Window images from Terra/Aqua MODIS and Suomi NPP VIIRS are shown below.

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images at 1620 UTC [click to enlarge]

Aqua MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Aqua MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images at 1801 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1835 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1835 UTC [click to enlarge]

Over the western Atlantic Ocean, strong winds associated with Florence created large waves which induced upwelling of colder water from below the ocean surface, as seen in Ocean Heat Content data (below).

Ocean Heat Content data from 14 September [click to enlarge]

Ocean Heat Content data from 14 September [click to enlarge]

Super Typhoon Mangkhut makes landfall in the Philippines

September 14th, 2018 |

Himawari-8 Infrared Window (10.4 µm) images [click to play MP4 animation]

Himawari-8 Infrared Window (10.4 µm) images [click to play MP4 animation | Animated GIF]

Himawari-8 Infrared Window (10.4 µm) images (above) showed Super Typhoon Mangkhut making landfall as a Category 5 intensity storm over the far northern portion of Luzon in the Philippines just after 17 UTC on 14 September 2018 (1 am local time on 15 September). The eye quickly deteriorated and became cloud-filled after moving inland.

The MIMIC-TC morphed microwave product (below) indicated that Mangkhut was in the process of completing an eyewall replacement cycle shortly before making landfall.

westernMIMIC-TC morphed microwave product [click to enlarge]Mangkhut moved over waters of the western Philippine Sea having high values of Ocean Heat Content and Sea Surface Temperature during the final day preceding landfall (below).

Ocean Heat Content and Sea Surface Temperature data along the path of Mangkhut [click to enlarge]

Hurricane Florence off the coast of North Carolina

September 13th, 2018 |

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

A toggle between NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (above) showed Category 2 Hurricane Florence off the coast of North Carolina at 0646 UTC on 13 September 2018. GCOM AMSR2 Microwave (89 GHz), Convective Rain Rate and Surface Rain Rate (below) indicated that the southern and southeastern portions of the eye and eyewall had become fragmented. (VIIRS and AMSR2 imagery courtesy of William Straka, CIMSS)

GCOM AMSR2 Microwave (89 GHz), Convective Rain Rate and Surface Rain Rate [click to enlarge]

GCOM AMSR2 Microwave (89 GHz), Convective Rain Rate and Surface Rain Rate [click to enlarge]

In a toggle between DMSP-17 SSMIS Microwave (85 GHz) and GOES-16 Infrared Window (10.3 µm) images from the CIMSS Tropical Cyclones site (below), microwave imagery revealed the very large internal core of the hurricane at 1216 UTC.

DMSP-17 SSMIS Microwave (85 GHz) and GOES-16 Infrared Window (10.3 µm) images [click to enlarge]

DMSP-17 SSMIS Microwave (85 GHz) and GOES-16 Infrared Window (10.3 µm) images [click to enlarge]

The Metop-A satellite passed over the western edge of Florence, with ASCAT sensing surface winds as high as 66 knots along the western edge of the storm core (below).

GOES-16

GOES-16 “Red” Visible (0.64 µm) image at 1427 UTC, with plots of buoy reports and Metop-A ASCAT surface scatterometer winds [click to enlarge]

Comparisons of Visible and Infrared Window images from Terra MODIS (1538 UTC), NOAA-20 VIIRS (1804 UTC) and Suomi NPP VIIRS (1854 UTC) are shown below.

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images at 1538 UTC [click to enlarge]

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images at 1538 UTC [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1804 UTC [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1804 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1854 UTC [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 1854 UTC [click to enlarge]

As Florence approached the coast, it moved over Gulf Stream waters as warm as 82-85ºF, as seen in a comparison of 12 September MODIS Sea Surface Temperature product and 13 September MODIS Visible images (below).

12 September Terra MODIS Sea Surface Temperature product and 13 September Terra MODIS Visible (0.65 µm) image [click to enlarge]

12 September Terra MODIS Sea Surface Temperature product and 13 September Terra MODIS Visible (0.65 µm) image [click to enlarge]

The strong winds associated with Florence created large waves which induced upwelling of colder water from below the ocean surface:


Overlapping GOES-16 (GOES-East) Mesoscale Domain Sectors were providing images every 30 seconds; “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) animations are shown below. Note that a secondary eyewall began to form following a convective burst which developed southwest of the eye around 1920 UTC (Visible | Infrared) — and as the new eyewall convection quickly wrapped around to the north, Cape Lookout, North Carolina (Buoy CLKN7) recorded a peak wind speed of 73 knots at 20 UTC and 21 UTC.

GOES-16

GOES-16 “Red” Visible (0.64 µm) images [click to play MP4 animation]

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images [click to play MP4 animation]

The large pattern of upper-tropospheric outflow was quite apparent on GOES-16 Near-Infrared “Cirrus” (1.37 µm) images (below) — spanning a distance of approximately 1000 miles.

GOES-16 Near-Infrared "Cirrus" (1.37 µm) images [click to play MP4 animation]

GOES-16 Near-Infrared “Cirrus” (1.37 µm) images [click to play MP4 animation]