Suomi NPP VIIRS Day/Night Band (0.7 µm) imagery, below, from before (23 August) and after (30 August) Hurricane Harvey’s 26 August landfall, shows changes in city light illumination associated with power outages. Click and drag the slider bar to swipe between the two images. A toggle between larger versions of the two images is available here.

(Imagery courtesy of William Straka, SSEC/CIMSS)

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

Meandering Tropical Storm Harvey is near the Gulf Coast of Texas during the day on Monday 28 August as shown in the 4-panel Animation above. The Four panels include, clockwise from lower left, Upper Level Water Vapor (6.19 µm), Lower Level Water Vapor (7.3 µm), Clean Window (10.3 µm) and Snow/Ice Channel (1.61 µm) (ABI Bands 8, 10, 13 and 5, respectively). The deepest and strongest convection with Harvey has shifted eastward into Louisiana; dry mid-tropospheric air is apparent in both water vapor infrared images; Convection continues near the center of the storm; onshore low-level flow is apparent in the Snow/Ice channel. Total Precipitable Water computed from Microwave Imagery (at this site), below, shows that abundant moisture remains over southeast Texas and Louisiana.

GOES-16 Visible Imagery (0.64 µm), below, show the center of Harvey to be just offshore (Click here for the latest National Hurricane Center advisories on Harvey), with moist low-level flow from the Gulf into southeast Texas and southwest Louisiana. Geostationary Lightning Mapper (GLM) observations of Lightning Groups (Events are grouped into Groups, Groups are grouped into Flashes), show scant lightning associated with the center of Harvey. More lightning activity is apparent over southeastern Louisiana (including some apparently spurious signals near Baton Rouge). A similar animation over Infrared Imagery is here.

For the latest on Harvey and its dangerous rainfall, consult the National Hurricane Center website, or the CIMSS Tropical Weather Website, or the Hydrologic Prediction Website.

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

As Harvey moved across warm waters in the northwestern Gulf of Mexico (SST | OHC), it continued to intensify (ADT | SATCON) to a Category 4 hurricane just before making landfall along the Texas coast around 03 UTC on 26 August 2017 (10 pm local time on 25 August). Overlapping 1-minute GOES-16 Mesoscale Sectors had been positioned over Harvey, providing images at 30-second intervals — “Red” Visible (0.64 µm) images prior to sunset (below) showed the approach of the eye. A comparison of GOES-16 vs GOES-13 (GOES-East) Visible images is available here.

Hurricane Harvey had a large-diameter eye in GOES-16 “Clean” Infrared Window (10.3 µm) images at landfall, which persisted — albeit becoming smaller with time — for several hours after it moved inland (below). A longer-term animation of 5-minute GOES-16 Infrared Window images (covering the period 23-27 August) is available here.

A sequence of four Infrared Window images from Suomi NPP VIIRS and Terra/Aqua MODIS covering the period 0419-0851 UTC (below) showed the shrinking eye and erratic path of Harvey once it moved inland then turned eastward.

A recap of the torrential rainfall amounts and maximum wind gusts caused by Hurricane Harvey can be seen in the WPC Storm Summary. A map showing the final storm total rainfall from Harvey is available here. [January 2018 update: the NHC released its final report on Hurricane Harvey]

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

The Geostationary Lightning Mapper (GLM) on GOES-16 allows observations of lightning associated with Hurricane Harvey in the Gulf of Mexico. The animation above, from 1247 to 1332 UTC on 25 August 2017, shows lightning group observations every minute, color-coded by time (red is the oldest, yellow is the most recent, corresponding to the nominal time of the ABI Image), superimposed on GOES-16 ABI Channel 1 Visible Imagery (0.47 µm). Most of the Hurricane lightning is in the outer bands of the storm, with very little in the central core. This distribution is not unusual.

(A similar animation from 1812-1857 UTC on 24 August 2017, when lightning was observed near the storm core, is here.)

(Thanks to Dave Santek, SSEC, for this animation!)

Added: The animation below (for 1352-1437 UTC on 25 August) is over simulated True-Color Imagery, and for this GLM plot, the latest 1-minute Groups plots (that correspond to the ABI Image time) are red, and the earliest are Yellow.

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