Category Archives: Aqua

Snowfall across the Deep South

GOES-13 Visible (0.63 µm) images [click to play animation]

GOES-13 Visible (0.63 µm) images [click to play animation]

GOES-13 (GOES-East) Visible (0.63 µm) images (above) showed a broad swath of snow cover from Louisiana to Virginia on 09 December 2017. Some notable storm total accumulations included 6.5 inches at Kentwood, Louisiana, 7.0 inches at Bay Springs, Mississippi, 12.0 inches at Jacksonville, Alabama, 2.0 inches at Century, Florida, 18.0 inches at Mountain City, Georgia, 7.0 inches near Roan Mountain, Tennessee, and 25 inches at Mt. Mitchell State Park, North Carolina. Daily record snowfall accumulations included a Trace at New Orleans, Louisiana, 5.1 inches at Jackson, Mississippi and 1 inch at Mobile, Alabama.

A closer view of GOES-13 visible images (below) showed the band of snow cover across Louisiana, Mississippi and Alabama. Much of the the snow melted quickly, due to warm ground temperatures and a full day of sun.

GOES-13 Visible (0.63 µm) images, with station identifiers plotted in yellow [click to play animation]

GOES-13 Visible (0.63 µm) images, with hourly surface reports plotted in yellow [click to play animation]

A more detailed view of the snow cover was provided by 250-meter resolution Terra and Aqua MODIS true-color Red-Green-Blue (RGB) images from the SSEC MODIS Direct Broadcast site (below). Note that snow cover was evident all the way to the Gulf Coast at Atchafalaya Bay, Louisiana early in the day.

Terra and Aqua MODIS true-color RGB images of the central Gulf Coast region [click to enlarge]

Terra and Aqua MODIS true-color images of the central Gulf Coast region [click to enlarge]

Terra and Aqua MODIS true-color RGB images, centered over Atchafalaya Bay, Louisiana [click to enlarge]

Terra and Aqua MODIS true-color RGB images, centered over Atchafalaya Bay, Louisiana [click to enlarge]

Terra and Aqua MODIS true-color images, centered over New Orleans, Louisiana [click to enlarge]

Terra and Aqua MODIS true-color images, centered over New Orleans, Louisiana [click to enlarge]

Terra MODIS true-color image, centered over Atlanta, Georgia [click to enlarge]

Terra MODIS true-color image, centered over Atlanta, Georgia [click to enlarge]

It is interesting to note that with the aid of reflected moonlight — the Moon was in the Waning Gibbous phase, at 59% of Full — the Suomi NPP VIIRS Day/Night Band (0.7 µm) was able to detect the area of deeper snow cover across southeastern Louisiana and southern Mississippi at 0741 UTC or 1:41 AM local time; this snow cover was then seen during the following morning on GOES-13 Visible (0.63 µm) imagery at 1440 UTC or 8:40 AM local time (below). A VIIRS instrument is part of the payload on the recently-launched JPSS-1/NOAA-20 satellite.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and GOES-13 Visible (0.63 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and GOES-13 Visible (0.63 µm) images [click to enlarge]

Wildfires in southern California

GOES-15 Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-15 Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-15 (GOES-West) Shortwave Infrared (3.9 µm) images (above; also available as an animated GIF) showed the rapid development of wildfires driven by strong Santa Ana winds in Southern California on 05 December 2017. The fire thermal anomalies or “hot spots” are highlighted by the dark black to yellow to red pixels — the initial signature was evident on the 0230 UTC image (6:30 PM local time on 04 December), however the GOES-15 satellite was actually scanning that particular area at 0234 UTC or 6:34 PM local time. The Thomas Fire (the largest of the fires) advanced very quickly toward the southwest, nearly reaching the coast.

Nighttime image toggles between Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) data at 0904 UTC and 1044 UTC (below) revealed the large fire hot spots, along with the extensive smoke plume that was drifting over the adjacent nearshore waters of the Pacific Ocean. With ample illumination from the Moon (which was in the Waning Gibbous phase, at 95% of Full), the “visible image at night” capability of the VIIRS Day/Night Band — which will also be available from the recently-launched JPSS-1/NOAA-20 satellite — was clearly demonstrated.

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) images, with plots of surface reports [click to enlarge]

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) images, with plots of surface reports [click to enlarge]

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) images, with plots of surface reports [click to enlarge]

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and Day/Night Band (0.7 µm) images, with plots of surface reports [click to enlarge]

A toggle between the two VIIRS Day/Night Band images (below; courtesy of William Straka, CIMSS) showed initial darkness resulting from fire-related power outages in Santa Barbara County to the north, and Ventura County to the south (in the Oxnard/Camarillo area).

Suomi NPP VIIRS Day/Night Band (0.7 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) images [click to enlarge]

This large wind-driven fire was also very hot — the maximum brightness temperature on the VIIRS 4.05 µm Shortwave Infrared image was 434.6 K or 322.6º F, which was above the saturation threshold of the VIIRS 3.75 µm Shortwave Infrared detectors (below).

Suomi NPP VIIRS 4.05 µm and 3.75 µm Shortwave Infrared images [click to enlarge]

Suomi NPP VIIRS 4.05 µm and 3.75 µm Shortwave Infrared images [click to enlarge]

In a comparison of daytime GOES-15 Visible (0.63 µm) and Shortwave Infrared (3.9 µm) images (below), the west-southwestward transport of smoke over the Pacific Ocean was clearly seen.

GOES-15 Visible (0.63 µm, top) and Shortwave Infrared (3.9 µm, bottom) images [click to play MP4 animation]

GOES-15 Visible (0.63 µm, top) and Shortwave Infrared (3.9 µm, bottom) images [click to play MP4 animation]

A more detailed view of the thick smoke originating from the 3 fires (from north to south: the Thomas, Rye and Creek fires) was provided by a 250-meter resolution Aqua MODIS true-color Red-Green-Blue (RGB) image from the MODIS Today site (below).

Aqua MODIS true-color RGB image [click to enlarge]

Aqua MODIS true-color RGB image [click to enlarge]

Immediately downwind of the Creek Fire, smoke was reducing the surface visibility to 1 mile at Van Nuys and adversely affecting air quality (below).

Time series plot of surface reports at Van Nuys, California [click to enlarge]

Time series plot of surface reports at Van Nuys, California [click to enlarge]

===== 06 December Update =====

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.75 µm and 4.05 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.75 µm and 4.05 µm) images [click to enlarge]

The fires in Southern California continued to burn into the following night, as shown by Suomi NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.75 µm and 4.05 µm) images (above; courtesy of William Straka, CIMSS). A large-scale view with Day/Night Band imagery revealed the extent of smoke transport westward over the Pacific Ocean.

GOES-15 Shortwave Infrared (3.9 µm) images (below) displayed the thermal signatures exhibited by the fires. Note the appearance of a new fire — the Skirball Fire — first appearing on the 1300 UTC (5:00 AM local time) image, just north of Santa Monica (KSMO). Although the Santa Ana winds were not quite as strong as the previous day, some impressive wind gusts were still reported.

GOES-15 Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

GOES-15 Shortwave Infrared (3.9 µm) images, with hourly surface plots [click to play MP4 animation]

A toggle between 250-meter resolution Terra (1911 UTC) & Aqua (2047 UTC) MODIS true-color images from MODIS Today (below) showed significant pyrocumulus development from a flare-up along the northeast perimeter of the Thomas Fire. The cloud plume only exhibited a minimum infrared brightness temperature of +5.5º C on the corresponding Aqua MODIS Infrared Window image, far above the -40ºC threshold assigned to pyroCumulonimbus clouds.

Comparison of Terra (1911 UTC) & Aqua (2047 UTC) MODIS true-color RGB images [click to enlarge]

Comparison of Terra (1911 UTC) & Aqua (2047 UTC) MODIS true-color RGB images [click to enlarge]

===== 07 December Update =====

Suomi NPP Day Night Band Imagery, 3-7 December 2017, over southern California

RealEarth imagery of the Day Night Band over 5 days (one image each night from 3 through 7 December), above, shows the evolution of the fire complex (Imagery courtesy Russ Dengel, SSEC). Similarly, a closer view of daily composites of VIIRS Shortwave Infrared (3.74 µm) imagery (below) revealed the growth and spread of the Thomas Fire from 04-07 December.

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) image composites [click to enlarge\

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) image composites [click to enlarge]

In a toggle between Terra MODIS true-color and false-color RGB images (below), the large burn scar of the Thomas Fire (shades of red to brown) was very apparent on the false-color image.

Terra MODIS true-color and false-color images [click to enlarge]

Terra MODIS true-color and false-color images [click to enlarge]

Prescribed burn in Wisconsin

GOES-16 Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images, with plots of hourly surface reports [click to play MP4 animation]

GOES-16 Visible (0.64 µm, left) and Shortwave Infrared (3.9 µm, right) images, with plots of hourly surface reports [click to play MP4 animation]

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

GOES-16 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above; also available as an animated GIF) showed signatures associated with a prescribed burn in western Wisconsin on 28 November 2017. The Shortwave Infrared images revealed a warm thermal anomaly or “hot spot” (dark black to yellow to red pixels) — and on the visible images, a thin smoke plume could be seen drifting southeastward from the fire source.

Early in the animation sequence, however, a band of cirrus cloud was moving over the fire — yet a faint thermal signature (darker gray to black pixels) could occasionally be seen on the Shortwave Infrared imagery. The cirrus cloud layer was thin enough to allow some of the heat energy emitted by the fire to pass through and reach the satellite detectors. Once the cirrus moved to the south, the fire’s hot spot became much more apparent.

A toggle between Terra MODIS Shortwave Infrared (3.7µm) and Infrared Window (11.0 µm) images at 1812 UTC (below) also showed a faint warm fire signature through the cirrus clouds — the cloud-top Infrared Window brightness temperature directly over the fire in northern Monroe County was -33ºC, while the warmest Shortwave Infrared brightness temperature of the subtle fire signature was +1ºC.

Terra MODIS Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Terra MODIS Shortwave Infrared (3.7 µm) and Infrared Window (11.0 µm) images [click to enlarge]

As was seen on the GOES-16 imagery, after the band of cirrus moved south of the fire an Aqua MODIS Shortwave Infrared (3.7 µm) image at 1912 UTC (below) displayed a pronounced fire hot spot signature.

Aqua MODIS Shortwave Infrared (3.7 µm) image [click to enlarge]

Aqua MODIS Shortwave Infrared (3.7 µm) image [click to enlarge]

(Thanks to Dave Schmidt, NWS La Crosse, for bringing this case to our attention!)

Lake/river effect clouds in North Dakota

GOES-16

GOES-16 “Red” Visible (0.64 µm, top) and Near-Infrared “Snow/Ice” (1.61 µm, bottom) images, with plots of hourly surface reports [click to play MP4 animation]

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

As cold arctic air continued to move eastward across North Dakota on 07 November 2017, GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) showed “lake effect” cloud plumes streaming east-northeastward from Lake Sakakawea (and also from Missouri River). The Snow/Ice images were the most useful for discriminating between supercooled water droplet cloud plumes (brighter shades of white) and the surrounding snow-covered land surfaces (darker shades of gray).

During the preceding nighttime hours, Suomi NPP VIIRS and Aqua MODIS Infrared Brightness Temperature Difference images (below) — the legacy “fog/stratus product” — revealed that the orientation of the Lake Sakakawea cloud plume changed as surface winds switched from northwesterly to westerly.

Infrared Brightness Temperature Difference images from Suomi NPP VIIRS (11.45 µm = 3.74 µm) and Aqua MODIS (11.0 µm - 3.7 µm) [click to enlarge]

Infrared Brightness Temperature Difference images from Suomi NPP VIIRS (11.45 µm = 3.74 µm) and Aqua MODIS (11.0 µm – 3.7 µm) [click to enlarge]

The Aqua MODIS Sea Surface Temperature product (below) indicated that the water in Lake Sakakawea was as warm as 47.9ºF (darker green enhancement) — significantly warmer than the surface air passing over it, which was generally in the 5 to 15ºF range.

Aqua MODIS Sea Surface Temperature product [click to enlarge]

Aqua MODIS Sea Surface Temperature product [click to enlarge]

The large cloud plume from Lake Sakakawea was also very evident on GOES-16 Day Snow-Fog Red-Green-Blue (RGB) images (below). Farther to the east, smaller and shorter-lived cloud plumes could also be seen originating from Devils Lake (along the Benson/Ramsey county line) and Stump Lake (in Nelson county).

GOES-16 Day Snow-Fog RGB images [click to animate]

GOES-16 Day Snow-Fog RGB images [click to animate]

Taking a closer look at the Lake Sakakawea area, the brighter signature of steam plumes rising from power plants located south and southeast of the lake (2 in Mercer county, and 1 in McLean county) could be spotted on the Day Snow-Fog RGB images (below).

GOES-16 Day Snow-Fog RGB images [click to animate]

GOES-16 Day Snow-Fog RGB images [click to animate]

Due to the low sun angle and the snow-covered land surface, morning shadows from these rising steam plumes could be seen on GOES-16 “Red” Visible (0.64 µm) images (below).

GOES-16

GOES-16 “Red” Visible images [click to animate]

Special thanks to Carl Jones (NWS Grand Forks) for bringing this case to our attention, and supplying the AWIPS RGB and Visible images at the bottom of the blog post.

 

Severe weather across Indiana and Ohio

GOES-16 Visible (0.64 µm, top) and Infrared Window (10.3 µm, bottom) images, with SPC storm reports plotted in red (on Visible images) and black (on Infrared images) [click to play MP4 animation]

GOES-16 Visible (0.64 µm, top) and Infrared Window (10.3 µm, bottom) images, with SPC storm reports plotted in red (on Visible images) and black (on Infrared images) [click to play MP4 animation]

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

An outbreak of severe weather occurred across the Midwestern US on 05 November 2017, with a number of tornadoes (including a 39-mile long track EF-2 tornado) in Indiana and Ohio. A GOES-16 Mesoscale Sector provided imagery at 1-minute intervals during this event — “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) with plots of SPC storm reports (T=tornado; W=damaging winds; H=hail) showed the development and motion of the severe thunderstorms. The locations of the plotted SPC storm reports have been parallax-corrected upward from the surface, to match a mean storm-top height of 10 km.

A toggle between Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images (below) showed a snapshot of the storm at 1803 UTC. SPC storm reports within about  +/- 30 minutes of the image time are also plotted. The coldest storm-top infrared brightness temperatures were -71ºC (black enhancement), over southern and eastern Indiana. The VIIRS instrument will also fly on the JPSS series of satellites.

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images, with plots of SPC storm reports [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images, with plots of SPC storm reports [click to enlarge]

One interesting aspect seen on 1806 UTC Aqua MODIS Water Vapor (6.7 µm) imagery (below) was the signature of strong subsidence (darker blue enhancement) immediately upwind — along the western edge — of the 2 larger areas of severe convection. Once again, SPC storm reports within about +/- 30 minutes of the image time are plotted.

Aqua MODIS Visible (0.65 µm), Infrared Window (11.0 µm) and Water Vapor (6.7 µm) images, with SPC storm reports [click to enlarge]

Aqua MODIS Visible (0.65 µm), Infrared Window (11.0 µm) and Water Vapor (6.7 µm) images, with SPC storm reports [click to enlarge]

Additional information on this event can be found on the Satellite Liaison Blog, as well as the NWS forecast offices at Indianapolis IN, Northern IN, and Wilmington OH.

Lake effect and river effect clouds in northeastern Montana

GOES-16 "Red" Visible (0.64 µm, top) and Near-Infrared "Snow/Ice" (1.61 µm, bottom) images, with hourly plots of surface observations [click to play MP4 animation]

GOES-16 “Red”Visible (0.64 µm, top) and Near-Infrared “Snow/Ice” (1.61 µm, bottom) images, with hourly plots of surface observations [click to play MP4 animation]

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

As arctic air began to spread eastward across Montana — where the coldest temperature in the US was -12ºF — behind an inverted trough (surface analyses) on 04 November 2017, GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) revealed bands of “lake effect” (from Fort Peck Lake) and “river effect” (slightly upstream, from the Missouri River) clouds. On the Snow/Ice images, sow cover (and cold ice crystal clouds) appear as darker shades of gray, in contrast to supercooled water droplet clouds which are brighter white. Note that surface air temperatures at Glasgow (KGGW) and Jordan (KJDN) were generally in the 15 to 20ºF range.

A 1-km resolution Aqua (overpass times) MODIS Sea Surface Temperature product (below) indicated that SST values were still 50ºF and warmer (darker shades of green) in parts of Fort Peck Lake. Farther to the west, a deeper portion of the Missouri River exhibited SST values in the mid-40s F (cyan) — this area  was likely the source of the river-effect cloud features. The temperature difference between the surface air and the warmer lake/river water was therefore in the 30-35ºF range.

Aqua MODIS Sea Surface Temperature product [click to enlarge]

Aqua MODIS Sea Surface Temperature product [click to enlarge]

In a toggle between 250-meter resolution Terra (overpass times) MODIS true-color (Bands 1/4/3) and false-color (Bands 7/2/1)  Red-Green-Blue (RGB) images from the MODIS Today site (below), the false-color image helps to highlight the bands of supercooled water droplet river effect and lake effect clouds (brighter white) — snow cover (and high-altitude ice crystal clouds) appear as shades of cyan.

Terra MODIS true-color and false-color RGB images [click to enlarge]

Terra MODIS true-color and false-color RGB images [click to enlarge]

A 30-meter resolution Lnndsat-8 false-color image (below) captured the dissipating remnants of the Missouri River cloud plume at 1800 UTC; a few cumulus cloud streets could also be seen over Fort Peck Lake, along the far eastern edge of the image swath.

Landsat-8 false-color image [click to enlarge]

Landsat-8 false-color image [click to enlarge]

Santa Ana winds in Southern California

GOES-16 Land Surface Temperature product, with hourly surface reports plotted in white [click to enlarge]

GOES-16 Land Surface Temperature product, with hourly surface reports plotted in white [click to enlarge]

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

The GOES-16 Land Surface Temperature product (above, courtesy of Jordan Gerth, CIMSS) revealed a dramatic increase in the land surface temperature (or surface “skin temperature”) following the onset of easterly/northeasterly Santa Ana winds in Southern California’s Ventura County during the overnight and early morning hours of 24 October 2017. Between 06-14 UTC (11 PM-7 AM local time), the surface air temperature increased from 66-91ºF at Oxnard (KOXR), 75-90ºF at Point Mugu (KNTD) and 77-91ºF at Camarillo (KCMA). Surface wind gusts of 32 mph were recorded at Camarillo during this period, although 64 mph was reported at South Mountain (elevation 2350 feet)..

A warming trend in that same area was also evident in the MODIS Land Surface Temperature product (below), during the time between the Terra (0539 UTC) and Aqua (0951 UTC) overpasses — LST values ranged from the low 60s F (lighter shades of yellow) to the upper 80s and low 90s F (darker shades of red) in the higher elevations.

Terra and Aqua MODIS Land Surface Temperature product [click to enlarge]

Terra and Aqua MODIS Land Surface Temperature product [click to enlarge]

A similar warming signature was seen over Ventura County on GOES-16 Shortwave Infrared (3.9 µm) images (below) — although an even more pronounced Santa Ana wind warming signal was evident farther to the southeast over Orange County (where winds gusted as high as 69 mph); note how the warmer orange-enhanced infrared brightness temperatures surged southwestward toward the coast.

GOES-16 Shortwave Infrared (3.9 µm) images [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm) images [click to play MP4 animation]

A number of record high temperatures resulted from this Santa Ana wind event:


Record high temperatures in the San Diego, California

Record high temperatures in the San Diego, California area

In fact, the highest temperature in the Lower 48 states that day was 108ºF at Miramar Naval Air Station and San Luis Obispo, California.

National Temperature extremes

National Temperature extremes

Ex-hurricane Ophelia over Ireland and the United Kingdom

Meteosat-10 Water Vapor (6.25 µm) images, with hourly surface wind gusts (knots) plotted in red [click to play MP4 animation]

Meteosat-10 Water Vapor (6.25 µm) images, with hourly surface wind gusts (knots) plotted in red [click to play MP4 animation]

After reaching Category 3 intensity over the eastern Atlantic Ocean on 14 October, Hurricane Ophelia (storm track) rapidly underwent transition to an extratropical storm which eventually spread high winds across much of Ireland and the United Kingdom on 16 October 2017. EUMETSAT Meteosat-10 upper-level Water Vapor (6.25 µm) (above) and lower-level Water Vapor (7.35 µm) images (below) revealed the familiar “scorpion tail” signature of a sting jet (reference). Hourly wind gusts (in knots) from primary reporting stations are plotted in red.

Meteosat-10 Water Vapor (7.35 µm) images, with hourly surface wind gusts (knots) plotted in red [click to play MP4 animation]

Meteosat-10 Water Vapor (7.35 µm) images, with hourly surface wind gusts (knots) plotted in red [click to play MP4 animation]

Two sites with notable wind gusts were Cork, Ireland (67 knots at 0930 UTC) and Valley, UK (70 knots at 1500 UT), shown below. In fact, a wind gust of 103 knots (119 mph or 191 km/hour) was reported at the Fastnet Rock Lighthouse off the southwest coast of Ireland.

Time series plot of surface data from Cork, Ireland [click to enlarge]

Time series plot of surface data from Cork, Ireland [click to enlarge]

Time series plot of surface data from Valley, United Kingdom [click to enlarge]

Time series plot of surface data from Valley, United Kingdom [click to enlarge]

———————————————————————————-

Terra and Aqua MODIS true-color images [click to enlarge]

Terra and Aqua MODIS true-color images [click to enlarge]

In a toggle between Terra MODIS (overpass time around 1159 UTC) and Aqua MODIS (overpass time around 1345 UTC) true-color Red/Green/Blue (RGB) imagery (above), a somewhat hazy appearance was seen over the Irish Sea on the Terra MODIS image. This was due to an airborne plume of sand from the Sahara Desert (UK Met Office story).

In fact, blowing sand was observed about 3 hours later at Isle of Man, from 1520-1620 UTC — during that time period their surface winds gusted to 68 knots (78 mph), and surface visibility was reduced to 2.2 miles (below).

Time series plot of surface data from Isle of Man [click to enlarge]

Time series plot of surface data from Isle of Man [click to enlarge]

Hurricane Harvey makes landfall

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

As Hurricane 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 (which occurred around 03 UTC on 26 August 2017, or 10 pm local time on 25 August). A GOES-16 Mesoscale Sector had been positioned over Harvey, providing images at 30-second intervals; some of these are shown with “Red” Visible (0.64 µm) images prior to sunset (below). A GOES-16 vs GOES-13 (GOES-East) Visible image comparison is available here.

GOES-16 Visible (0.64 µm) images, with hourly surface ports plotted in yellow (Click to play MP4 animation)

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface ports plotted in yellow [click to play MP4 animation]

Hurricane Harvey had a large eye on GOES-16 “Clean” Infrared Window (10.3 µm) images at landfall, which persisted — albeit becoming smaller with time — for many 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.

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images, with hourly surface reports plotted in yellow [click to play MP4 animation]

A sequence of 4 Infrared Window images, from Suomi NPP VIIRS and Terra/Aqua MODIS, covering the period 0419-0851 UTC (below) showed the shrinking eye and the erratic path of Harvey once it moved inland.

Terra/Aqua MODIS (11.0 µm) and Suomi NPP VIIRS (11.45 µm) Infrared Window images [click to enlarge]

Terra/Aqua MODIS (11.0 µm) and Suomi NPP VIIRS (11.45 µm) Infrared Window images [click to enlarge]

A recap of the torrential rainfall amounts and maximum wind gusts caused by Hurricane Harvey can be seen in the WPC Storm Summary.

Wildfire burning in Greenland

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation]

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation]

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

GOES-16 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above; a zoomed-in version is available here) displayed a subtle hazy signature of a smoke plume along with an intermittent “hot spot” (darker black pixels) associated with  a small fire — located near the center of the cyan circle — that was burning close to the southwest coast of Greenland on 01 August 2017. The approximate latitude/longitude coordinates of the fire were 67.87º N / 51.48º W, a location about halfway between Ilulissat (station identifier BGJN) and Kangerlussuaq (station identifier BGSF) and about halfway between the western edge of the Greenland Ice Sheet and the west coast .

Closer views using daily composites of 250-meter resolution Terra and Aqua MODIS true-color Red/Green/Blue (RGB) images (from 30 July to 04 August), sourced from RealEarth (below) indicated that the fire may have started close to 1540 UTC on 31 July — when a small white smoke and/or cloud feature (just north of the cursor) was seen at the fire source location on the Terra image (overpass time). The Aqua overpass time was around 1600 UTC.

Daily composites of Terra MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Terra MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Similar daily composite RGB images from Suomi NPP VIIRS (31 July to 04 August) are shown below. Note that the initial fire signature was not seen on the 31 May VIIRS image, due to the earlier overpass time  (1513 UTC) of the Suomi NPP satellite.

Daily composites Suomi NPP VIIRS true-color RGB images,.from 31 July to 04 August [click to enlarge]

Daily composites of Suomi NPP VIIRS true-color RGB images,.from 31 July to 04 August [click to enlarge]

On 03 August, a 1507 UTC overpass of the Landsat-8 satellite provided a 30-meter resolution Operational Land Imager (OLI) false-color RGB image of the fire (below). This was the same day that a pilot took photos of the fire, as reported on the Wildfire Today site.

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 OLI false-color RGB image [click to enlarge]

A comparison of one “before” (27 July) and two “after” (03 and 05 August) Landsat-8 OLI false-color RGB images (below) showed differences in smoke plume transport as the wind direction changed.

Landsat-8 false-color images on 27 July, 03 August and 05 August [click to enlarge]

Landsat-8 OLI false-color images on 27 July, 03 August and 05 August [click to enlarge]

It is possible that this “natural fire” is similar to the Smoking Hills type of spontaneous combustion that has been observed in the Canadian Arctic (thanks to Ray Hoff, retired UMBC Professor of Physics, for that tip).

Credit to Mark Ruminski (NOAA/NESDIS) for first bringing this interesting event to our attention.

===== 09 August Update =====

The animations of daily Terra and Aqua true-color RGB images (below) have been extended to 09 August and 08 August, respectively.

Daily composites of Terra MODIS true-color RGB images, from 30 July to 09 August [click to enlarge]

Daily composites of Terra MODIS true-color RGB images, from 30 July to 09 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 08 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 08 August [click to enlarge]

Suomi NPP VIIRS true-color RGB images from 04-09 August (below) include VIIRS-detected fire locations plotted in red. The 09 August image showed that smoke from the fire had drifted west-southwestward over the adjacent offshore waters of Davis Strait.

Daily composites of Suomi NPP VIIRS true-color RGB images, from 04-09 August, with fire detection points plotted in red [click to enlarge]

Daily composites of Suomi NPP VIIRS true-color RGB images, from 04-09 August, with fire detection points plotted in red [click to enlarge]

===== 12 August Update =====

Landsat-8 OLI false-color images on 03, 05 and 12 August [click to enlarge]

Landsat-8 OLI false-color images on 03, 05 and 12 August [click to enlarge]

Another overpass of Landsat-8 on 12 August provided a glimpse of the fire burn scar, which appeared as a darker hue of reddish-brown. Note that the fire had burned eastward to the coast, during a day when stronger westerly winds prevailed.

Related sites:

NASA Earth Observatory

NPR

ESA Space in Images

AGU EOS