Rapid Intensification of Hurricane Maria just to the east of the Leeward Islands

September 18th, 2017 |

GOES-16 “Clean Window” Infrared 10.3 µm imagery, 1600-2017 UTC on 18 September 2017 (Click to animate). Note: The Label states GOES-17 in error, and the time annotation becomes stuck for a time.

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

Hurricane Maria underwent rapid intensification on 18 September as it moved through very warm waters to the east of the Leeward Islands. The animation of GOES-16 “Clean Window” Infrared Imagery (10.3 µm), above, shows the rapid development of a warm concentric eye between 1640 and 1940 UTC. The toggle below, between 1600 UTC and 2000 UTC, testifies to a great increase in organization and strength. Click here for an mp4 animation from 1400 UTC to 2100 UTC on 18 September showing the intensification in the Visible (0.64 µm) channel from ABI.

GOES-16 “Clean Window” Infrared 10.3 µm imagery, 1600 and 2017 UTC on 18 September 2017 (Click to enlarge). Note: The Label states GOES-17 in error.

The storm is in an environment of very low shear (below) and moving towards warm water that is quite deep as depicted by large values of Oceanic Heat Content (bottom). (Maps found at this site).

850-250 hPa wind shear, 1800 UTC on 18 September 2017 (Click to enlarge)

Oceanic Heat Content analysis, 1800 UTC on 18 September 2017. (Click to enlarge). Note the relative cool wake north of the Leeward Islands left behind by Hurricane Irma.

Geostationary Lightning Mapper (GLM) data over Maria for the two hours ending 2045 UTC on 18 September (from this site; click here for infrared imagery), shows lightning within the southern eyewall of the storm.

GLM Group Observations in 3-minute intervals plotted on top of GOES-16 Visible (0.64 µm) Imagery, 1830-2045 UTC on 18 September 2017 (Click to enlarge)

For more information on this dangerous storm, refer to the webpages of the National Hurricane Center, or to the CIMSS Tropical Weather website. People in the Leeward Islands in particular should pay close attention to this storm.

Hurricane Irma moves along the north coast of Cuba

September 9th, 2017 |

GOES-16 “Clean Window” Infrared Imagery (10.3 µm) from 0357 to 1202 UTC on 9 September 2017 (Click to animate)

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

Hurricane Irma hit Cuba as a category 5 Storm late on 8 September 2017. The animation above shows the storm paralleling the north coast of Cuba; outer rainbands are moving into southern Florida. Irma is forecast to turn northwest and north during the day on 9 September, and then move up along the Gulf Coast of Florida, threatening the entire Florida Peninsula with Hurricane-force winds. Irma’s prolonged proximity to the Cuban landmass has affected the storm’s structure and its satellite presentation.  (Compare this animation above to one from 8 September in this blog post). The microwave animation, below, (source) suggests that the disruption to the storm might include the eyewall, and the central pressure of the storm has increased.

Morphed Microwave Imagery of Irma for the 24 hours ending around 0900 UTC on 9 September 2017 (Click to enlarge)

 

850-250 hPa Wind Shear over Irma, 0900 UTC on 9 September (Click to enlarge)

Wind shear in the atmosphere, shown above as 850-250 mb wind shear (Source), remains very low over the storm.   Shear will increase over the storm during the day however as it moves north.  This could slow any intensification that might occur as the storm moves over the very warm waters of the Florida Straits and eastern Gulf of Mexico, where Sea-Surface Temperatures are 30-32 C.

The latest Geostationary Lightning Mapper data over the storm (from this source) as the sun rises, shows little lightning over the center of Irma.

GOES-16 Visible (0.64 µm) Imagery at 15-minute intervals underneath plots of GLM Group Activity in 3-minute intervals, 0945-1200 UTC9 September 2017 (Click to enlarge)

William Straka, CIMSS, provided the Suomi NPP Visible (from the Day Night Band) and Infrared Imagery below.

Suomi NPP VIIRS Day Night Band Visible (0.7 µm) from 0619 UTC on 9 September 2017 (Click to enlarge)

Suomi NPP VIIRS Infrared Imagery (11.45 µm) from 0619 UTC on 9 September 2017 (Click to enlarge)

A zoomed-in, annotated view of the eye is below. (Click here for an image with no labels)

Annotated Suomi NPP VIIRS Day Night Band Visible (0.7 µm) from 0619 UTC on 9 September 2017 (Click to enlarge)

For further information on this dangerous storm, consult the National Hurricane Center, or the CIMSS Tropical Weather Website.

Category 4 Hurricane Jose approaches the Leeward Islands

September 8th, 2017 |

GOES-16 Clean Window (10.3 µm) Infrared Imagery, 1715 UTC on 8 September 2017 (Click to enlarge)

 

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

Hurricane Jose is approaching the Leeward Islands, following Irma’s path through the region earlier in the week. The Category 4 storm is shown above in 10.3 µm Infrared Imagery from GOES-16. Its satellite presentation is excellent. Geostationary Lightning Mapper (GLM) Lightning data (from this site) plotted on top of ABI Visible (0.64 µm) Imagery is shown below.

3-minute Aggregates of GLM Group Lightning plots and ABI Visible imagery (0.64 µm) at 15 minute intervals, 2 hours ending 1745 UTC on 8 September 2017 (Click to enlarge)

 

Cirrus outflow from Hurricane Irma is visible in the Visible/GLM animation above over and to the west of the Lesser Antilles.  That shear is not yet affecting Jose.

For more information on Jose, consult the webpages of the National Hurricane Center, or the CIMSS Tropical Weather Website.

Hurricane Irma north of Hispaniola

September 7th, 2017 |

GOES-16 Low-Level Water Vapor Infrared (7.34 µm) Imagery, 0737 – 1232 UTC on 7 September 2017 (Click to animate)

GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing

GOES-16 Captured very strong Hurricane Irma, north of Hispaniola, early on the day on 7 September. The 7.34 µm channel shown is sensitive to water vapor, that is, water vapor in the atmosphere absorbs energy at 7.34 µm. The animation shows the storm moving steadily to the west-northwest. A far less-organized Hurricane Katia is over the southwestern Gulf of Mexico, with a strong jet extending from Katia northeastward along the east coast. A short animation of Visible Imagery with Geostationary Lightning Mapper data, below, from 1015-1230 UTC, shows considerable lightning activity continuing in the eye of the storm and in some of the convective bands that surround it.

GOES-16 Visible (0.64 µm) Imagery at 15-minute intervals underneath plots of GLM Group Activity in 3-minute intervals, 1015-1230 UTC 7 September 2017 (Click to animate)

Suomi NPP overflew Irma at about 1800 UTC on 7 September. Visible (0.64 µm) and Infrared (11.45 µm) imagery from the VIIRS Instrument on Suomi NPP is below.

Suomi NPP VIIRS Visible (0.64 µm) imagery, 1808 UTC on 7 September 2017 (Click to enlarge)

Suomi NPP VIIRS Infrared (11.45 µm) imagery, 1808 UTC on 7 September 2017 (Click to enlarge)