CIMSS Satellite Blog
A weblog of meteorological satellite imagery relevant to current weather eventsSat, 25 Jun 2016 15:34:44 +0000en-UShourly1https://wordpress.org/?v=4.5.3Deadly tornado in Yancheng, China
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Himawari-8 0.64 µm Visible (top) and 10.4 µm Infrared Window (bottom) images [click to play animation]
Himawari-8 AHI Visible (0.64 µm) and Infrared Window (10.4 µm) images (above) showed the east-southeastward propagation of a mesoscale convective system which produced a deadly tornado in Yancheng, China around 2:30 pm local time on 23 June 2016 (Weather Underground blog). The location of Yancheng (33°23?N, 120°7?E) is denoted by the cyan * symbol, and the animation briefly pauses on the 0630 UTC images which match the reported time of the tornado. Overshooting tops are evident on the visible imagery, and cloud-top infrared brightness temperatures of -80º C or colder (violet colorenhancement) also appear, even after the storm crossed the coast and moved over the adjacent offshore waters of the Yellow Sea (note: due to parallax, the apparent location of the storm top features is displaced several miles to the north-northwest of their actual position above the surface). The spatial resolutions (0.5 km visible, 2 km infrared) of the AHI images are identical to those of the corresponding spectral bands that will be available from the ABI instrument on GOES-R.
An experimental version of the MIMIC Total Precipitable Water product which uses the MIRS retrieval TPW from POES, Metop, and Suomi NPP VIIRS satellites (below) revealed the band of high moisture pooled along the Mei-yu front, which appeared to surge northward across eastern China early in the day on 23 June.
MIMIC Total Precipitable Water product [click to play animation]
The 23 June/00 UTC rawinsonde report from Nanjing (located about 260 km southwest of Yancheng) indicated a total precipitable water value of 66.2 mm or 2.6 inches (below).
Nanjing, China rawinsonde report [click to enlarge]
http://cimss.ssec.wisc.edu/goes/blog/archives/21499/feed0First full day of Summer: snow in the Brooks Range of Alaska
http://cimss.ssec.wisc.edu/goes/blog/archives/21477#respondWed, 22 Jun 2016 23:59:32 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21477
GOES-15 Water Vapor (6.5 µm) images [click to play animation]
GOES-15 (GOES-West) Water Vapor (6.5 µm) images (above) showed the southeastward migration of an upper-level low across the North Slope and the eastern Brooks Range of Alaska during the 21 June – 22 June 2016 period. A potential vorticity (PV) anomaly was associated with this disturbance, which brought the dynamic tropopause — taken to be the pressure of the PV 1.5 surface — downward to below the 600 hPa pressure level over northern Alaska. Several inches of snow were forecast to fall in higher elevations of the eastern portion of the Brooks Range.
With the very large satellite viewing angle (or “zenith angle”) associated with GOES-15 imagery over Alaska — which turns out to be 73.8 degrees for Fairbanks — the altitude of the peak of the Imager 6.5 µm water vapor weighting function (below) was shifted to higher altitudes (in this case, calculated using rawinsonde data from 12 UTC on 22 June, near the 300 hPa pressure level).
GOES-15 Imager water vapor (Band 3, 6.5 µm) weighting function [click to enlarge]
The ABI instrument on GOES-R will have 3 water vapor bands, roughly comparable to the 3 water vapor bands on the GOES-15 Sounder — the weighting functions for those 3 GOES-15 Sounder water vapor bands (calculated using the same Fairbanks rawinsonde data) are shown below. Assuming a similar spatial resolution as the Imager, the GOES-15 Sounder bands 11 (7.0 µm, green) and 12 (7.4 µm, red) would have allowed better sampling and visualization of the lower-altitude portion of this particular storm system. The 3 ABI water vapor bands are nearly identical to those on the Himawari-8 AHI instrument; an example of AHI water vapor imagery over part of Alaska can be seen here.
GOES-15 Sounder water vapor weighting function plots [click to enlarge]
As the system departed and the clouds began to dissipate on 22 June, GOES-13 Visible (0.63 µm) images (below) did indeed show evidence of bright white snow-covered terrain on the northern slopes and highest elevations of the Brooks Range.
GOES-15 Visible (0.63 µm) images [click to play animation]
A sequence of 1-km resolution POES AVHRR Visible (0.86 µm) images (below) showed a view of the storm during the 21-22 June period, along with the resultant snow cover on 22 June. However, the snow quickly began to melt as the surface air temperature rebounded into the 50’s and 60’s F at some locations.
POES AVHRR Visible (0.86 µm) images [click to play animation]
The increase in fresh snow cover along the northern slopes and the highest elevations of the central and northeastern Brooks Range — most notably from Anaktuvuk Pass to Fort Yukon to Sagwon — was evident in a comparison of Suomi NPP VIIRS true-color Red/Green/Blue (RGB) images from 17 June and 22 June, as viewed using RealEarth (below). The actual time of the satellite overpass on 22 June was 2134 UTC.
Suomi NPP VIIRS true-color RGB images, 17 June and 22 June [click to enlarge]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21477/feed0Southwest US summer solstice: smoke, and solar panels
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Suomi NPP VIIRS Day/Night Band (0.7 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]
A nighttime comparison of Suomi NPP VIIRS Day/Night Band (0.7 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images at 0853 UTC on 20 June 2016(above) revealed 2 key features of the large Cedar Fire that had been burning in eastern Arizona: (1) the fire “hot spot” signature (black to yellow to red pixels) on the Shortwave Infrared image, located about 20 miles southwest of Show Low (KSOW), and (2) an approximately 50-mile-wide pall of dense smoke aloft — illuminated by a nearly-full Moon — that had drifted westward then northwestward during the previous 24 hours and was centered northwest of Prescott (KPRC). Note that there was no signature of this smoke feature on the Infrared Window image, since smoke is effectively transparent to infrared radiation.
During the following afternoon hours, a toggle between 2117 UTC Aqua MODIS Near-Infrared “Cirrus detection” (1.61 µm), Visible (0.65 µm), Infrared Window (11.0 µm) and Topography images (below) showed that the smoke aloft had moved northward during the day and was over far northwestern Arizona and southwestern Utah. On the Visible image, the dense layer of smoke obscured the view of surface features that are normally seen on a cloud-free day, but the edges of the smoke feature were difficult or impossible to identify. However, the smoke feature was quite evident on the Near-Infrared “Cirrus detection” image — due to the fact that this spectral band (which will be on the GOES-RABI instrument) is useful for detecting features composed of particles that are efficient scatterers of light (such as cirrus cloud ice crystals, airborne dust or volcanic ash, and in this case, smoke). As was seen in the VIIRS example above, there was no signature of the smoke on the Infrared Window image — the cooler (lighter gray) shades seen in that region were a result of higher terrain that exhibited cooler brightness temperatures due to more abundant vegetation.
Aqua MODIS Near-Infrared Cirrus (1.61 µm), Visible (0.65 µm), Infrared Window (11.0 µm), and Topography images [click to enlarge]
An animation of GOES-15 (GOES-West) Visible (0.63 µm) images (below) showed the aforementioned Cedar Fire smoke in northwestern Arizona early in the day (highlighted by a favorable forward scattering sun-satellite geometry), and also showed the smaller smoke plume from the Reservoir Fire that had just begun burning northeast of Los Angeles. In addition, the brief appearance of bright white flashes across Southern California and extreme southern Nevada (as seen on the 1800, 1830, 1841 and 1845 UTC images) were a result of reflection of sunlight from large solar panel farms.
GOES-15 Visible (0.63 µm) images [click to play animation]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21463/feed0Localized heavy rainfall and flooding in south-central Wisconsin
http://cimss.ssec.wisc.edu/goes/blog/archives/21448#respondWed, 15 Jun 2016 12:59:54 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21448
GOES-13 Infrared Window (10.7 µm) images [click to play animation]
GOES-13 Infrared Window (10.7 µm) images (above) showed the development of several rounds of deep convection which moved over parts of southern Wisconsin during the 14 June – 15 June 2016 period; these storms were responsible for heavy rainfall at some locations (NWS Milwaukee summary). As mentioned in a WPC Mesoscale Precipitation Discussion, some of these storms were focused along the nose of a low-level jet that was helping to push a warm frontal boundary (surface analyses) through the region. Moisture was also abundant south of the warm front, with a total precipitable water value of 55.1 mm (2.17 inches) seen in rawinsonde data from Davenport IA.
Landsat-8 false-color image [click to enlarge]
A timely cloud-free overpass of the Landsat-8 satellite on the morning of 15 June provided a 30-meter resolution false-color image as viewed using RealEarth(above), which showed areas of flooding — water appears as darker shades of blue — in the Black Earth area of western Dane County in southern Wisconsin. A before/after comparison of Landsat-8 images processed using an equation to highlight water as blue (below,courtesy of Shane Hubbard, SSEC/CIMSS) revealed the areas of inundation due to the 14-15 June thunderstorms.
Landsat-8 derived water change, 30 May vs 15 June 2016 [click to enlarge]
Aerial footage from a drone flight (below) showed vivid images of the flooding along Black Earth Creek.
YouTube video from drone flight near Black Earth, Wisconsin [click to play]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21448/feed025-year anniversary of the 1991 Mount Pinatubo eruption
http://cimss.ssec.wisc.edu/goes/blog/archives/21415#respondWed, 15 Jun 2016 02:59:31 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21415
GMS-4 Infrared Window (11.5 µm) images [click to play animation]
During the first 2 weeks of June 1991 the Mount Pinatubo volcano on the island of Luzon in the Philippines began to produce a series of eruptions, culminating in the climactic eruption beginning at 0227 UTC on 15 June. An animation of 5-km resolution GMS-4 Infrared Window (11.5 µm) images (above) spans the period from 1831 UTC on 12 June to 1831 UTC on 16 June, and showed the very large volcanic cloud following the 15 June eruption (the animation pauses at the 0230 UTC image on 15 June — just after the time of the major eruption). Also evident in the imagery was the westward movement of what became Category 3 Typhoon Yunya (known locally in the Philippines as Diding) toward Luzon. A larger-scale version of the animation is available here.
A closer view of the GMS-4 Infrared Window (11.5 µm) images (below) revealed interesting characteristics of the volcanic plume which penetrated the tropopause (which was at an air temperature of around -83º C, according to nearby rawinsonde reports) during the 3-8 hours following the onset of the 0227 UTC eruption. Note the initial appearance of a small area of very warm IR cloud-top IR brightness temperatures (-21.6º C at 0631 UTC, and -25.7º C at 0730 UTC) which then blossomed outward and became a westward-moving stratospheric plume that was notably warmer than the majority of the cold volcanic cloud canopy (which exhibited IR brightness temperatures in the -80º to -90º C range, denoted by the violet to yellow color enhancement).
GMS-4 Infrared Window (11.5 µm) images [click to enlarge]
NOAA-10 AVHRR Infrared Window (10.8 µm), Visible (0.91 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]
A higher-resolution (1.1-km) view of the post-eruption cloud was provided by NOAA-10 AVHRR images at 1034 UTC on 15 June (above). Even though it was just past sunset over the Philippines, the narrow stratospheric plume could be seen towering above the canopy of the main volcanic cloud (the plume was at a high enough altitude — estimated at a maximum of 40 km (reference 1 | reference 2) — to still be illuminated by sunlight). The summit of Pinatubo is located 8.7 miles/14 km west-southwest of what was then Clark Air Force Base (station identifier RPLC). On the 10.8 µm Infrared Window image, cloud-top gravity waves could be seen propagating radially outward from the overshooting top located above the volcano (which exhibited a minimum IR brightness temperature of -86º C, violet color enhancement). Note the much warmer IR brightness temperatures (as warm as -31º C, green color enhancement) associated with the stratospheric plume just off the west coast of Luzon. A closer view is available here.
About 10 hours prior to the climactic eruption, a volcanic ash cloud from one of the earlier eruptions was captured by NOAA-10 AVHRR images at 2329 UTC on 14 June (below). Around this same time it can be seen that Yunya was making landfall as a minimal-intensity typhoon along the eastern coast of Luzon. A closer view is available here.
NOAA-10 AVHRR Infrared Window (10.8 µm), Visible (0.91 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21415/feed0Mesoscale Convective Vortex (MCV) in Texas
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GOES-13 Infrared Window (10.7 µm) images [click to play animation]
GOES-13 Infrared Window (10.7 µm) images (above) showed a large Mesoscale Convective System (MCS) that developed in far eastern New Mexico after 2000 UTC on 11 June 2016, then moved eastward and eventually southward over West Texas during the nighttime hours on 12 June. The MCS produced wind gusts to 75 mph and hail of 1.00 inch in diameter in Texas (SPC storm reports).
Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images [click to enlarge]
Suomi NPP VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0801 UTC or 3:01 am local time (above) showed cloud-top infrared brightness temperatures were as cold as -83º C (violet color enhancement), along with a number of bright streaks on the Day/Night Band image due to cloud illumination by intense lightning activity (there were around 5000 cloud-to-ground lightning strikes associated with this MCS). On the infrared image, note the presence of cloud-top gravity waves propagating outward away from the core of overshooting tops.
This MCS produced heavy rainfall, with as much as 3.44 inches reported near Lomax (NWS Midland TX rainfall map | PNS). An animation of radar reflectivity (below, courtesy of Brian Curran, NWS Midland) showed the strong convective cells moving southward (before the Midland radar was struck by lightning and temporarily rendered out of service).
Midland, Texas radar reflectivity [click to play MP4 animation]
During the subsequent daytime hours, GOES-13 Visible (0.63 µm) images (below) revealed the presence of a large and well-defined Mesoscale Convective Vortex (MCV) as the cirrus canopy from the decaying MCS eroded. A fantastic explanation of this MCV was included in the afternoon forecast discussion from NWS Dallas/Fort Worth. New thunderstorms were seen to develop over North Texas during the late afternoon and early evening hours as the MCV approached — there were isolated reports of hail and damaging winds with this new convection (SPC storm reports). Initiation of this new convection may have also been aided by convergence of the MCV with a convective outflow boundary moving southward from Oklahoma.
GOES-13 Visible (0.63 µm) images [click to play animation]
A sequence of Visible images from POES AVHRR (0.86 µm), Terra MODIS (0.65 µm), and Suomi NPP VIIRS (0.64 µm) (below) showed snapshots of the MCV at various times during the day.
Visible images from POES AVHRR (0.86 µm), Terra MODIS (0.65 µm), and Suomi NPP VIIRS (0.64 µm) [click to enlarge]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21393/feed0Canada’s first tornado warning of 2016
http://cimss.ssec.wisc.edu/goes/blog/archives/21376#respondThu, 09 Jun 2016 23:59:48 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21376
GOES-13 Visible (0.63 µm, top) and Infrared Window (10.7 µm, bottom) images [click to play animation]
GOES-13 (GOES-East) Visible (0.63 µm) and Infrared Window (10.7 µm) images (above) showed that a cluster of thunderstorms began to develop in far southeastern Saskatchewan around 20 UTC on 09 May 2016, which quickly grew into a large supercell thunderstorm that moved across southwestern Manitoba. This thunderstorm exhibited overshooting tops and a prominent anvil-top plume in the visible images, along with a well-defined “enhanced-V” storm top signature in the Infrared imagery. The minimum cloud-top infrared brightness temperature was -66º C at 2230 UTC.
A higher resolution view was provided by POES AVHRR Visible (0.86 µm) and Infrared (12.0 µm) imagery at 2332 UTC (below) — details of the overshooting top, anvil plume, and enhanced-V signature showed up very well in the 1-km resolution images.
POES AVHRR Visible (0.86 µm) and Infrared (12.0 µm) images, with surface reports [click to enlarge]
Although the storm produced a funnel cloud (prompting the issuance of Canada’s first tornado warning of 2016):
no tornado was confirmed. There were reports of golfball-size hail at Lauder (located just northeast of Melita, Manitoba CWEI) and wind gusts to 96 km/hour or 56 knots at Killarney (located east of Melita).
POES AVHRR CLAVR-x Cloud Top Temperature and Cloud Top Height products (below) indicated minimum values of -76º C and maximum values of 13 km, respectively.
POES AVHRR Cloud Top Temperature and Cloud Top Height products [click to enlarge]
A surface frontal analysis (below) showed that the thunderstorms formed in the broad warm sector of a large occluded low pressure system centered in Saskatchewan, with a secondary low moving eastward across northern North Dakota — the RTMA surface wind field depicted the broad southerly flow of warm, moist air into Manitoba ahead of the storms (in addition to an interesting area of strong southwesterly flow into the rear flank of the storm).
POES AVHRR Infrared (12.0 µm) image, with surface fronts and RTMA surface winds [click to enlarge]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21376/feed0Wildfire on the Kamchatka Peninsula of Russia
http://cimss.ssec.wisc.edu/goes/blog/archives/21363#respondTue, 07 Jun 2016 12:59:55 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21363
Himawari-8 Visible (0.64 µm) images [click to play animation]
A large wildfire had been burning for several days from late May into early June 2016 (VIIRS fire detection hot spots) near the west coast of the Kamchatka Peninsula of Russia. On 07 June, Himawari-8 Visible (0.64 µm) images (above) showed smoke from the wildfire which became entrained within the clockwise circulation of a weak area of low pressure (surface analyses) just off the coast over the Sea of Okhotsk. Beneath the smoke aloft, a swirl of low-level stratus cloud associated with this low was also very apparent. Other features of interest seen in the 0.5 km resolution 10-minute imagery include the intermittent formation of standing wave clouds over the high terrain (east of the fire), and small ice floes drifting westward just off the coast of Magadan Oblast (northwest of the fire).
A closer view using Himawari-8 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (below) revealed numerous hot spots (dark black to yellow to red pixels) around the periphery of the burn scar of the large fire, along with the brief development of small pyrocumulus clouds over some of the larger, more active fires. Note that the ABI instrument on GOES-R will provide similar imagery at high spatial (0.5 km visible, 2 km infrared) and temporal (5 minute Full Disk coverage) resolutions.
Himawari-8 0.64 µm Visible (top) and 3.9 µm Shortwave Infrared (bottom) images [click to play animation]
A Suomi NPP VIIRS true-color Red/Green/Blue (RGB) image viewed using RealEarth(below) provided a high-resolution view of the fire region and the plume of smoke curving around the low pressure feature.
Suomi NPP VIIRS true-color image [click to enlarge]
]]>http://cimss.ssec.wisc.edu/goes/blog/archives/21363/feed0Tropical Storm Colin in the Gulf of Mexico
http://cimss.ssec.wisc.edu/goes/blog/archives/21341#respondMon, 06 Jun 2016 02:39:58 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21341
MIMIC Total Precipitable Water derived from Microwave imagery, 2300 UTC 02 June – 2200 UTC 05 June [click to enlarge]
The 2016 Atlantic Tropical Season’s third named storm has formed in the Gulf of Mexico just north of the Yucatan Peninsula; Colin became the earliest named “C” storm on record for that basin. MIMIC Total Precipitable Water values for the 72 hours ending at 2300 UTC on 5 June 2016, above, show the storm embedded within a deep band of tropical moisture that has surged northward from the Monsoon Trough / Intertropical Convergence Zone into the northwestern Caribbean and southern Gulf of Mexico (MIMIC TPW + surface analyses). Moisture extends northeastward along the projected path of the storm into northern Florida. Extensive rains are likely over the Southeast US as the storm moves north. Total Precipitable Water (TPW) from MIMIC is a simple band difference between two microwave channels; that difference is invalid over land where emissivity is highly variable. However, MIRS data can estimate TPW over land and water, and its distribution over the eastern United States, below, derived from a morphed animation of the observations, gives a better indication of the spread of rich moisture over the southeastern United States. In addition, the Blended TPW Product showed values in excess of 70 mm (2.76 inches) over the Gulf of Mexico, which were in excess of 170% of Normal.
MIRS-based Total Precipitable Water, 2300 UTC 05 June [click to enlarge]
Colin was poised to moved over a region of higher Ocean Heat Content that was located in the eastern Gulf of Mexico, which could help to fuel additional bursts of deep convection similar to that seen on POES AVHRR infrared imagery, below. For more information on Tropical Storm Colin, refer to the CIMSS Tropical Cyclones site and the National Hurricane Center.
POES AVHRR Visible (0.86 µm) and Infrared (12.0 µm) images [click to enlarge]
http://cimss.ssec.wisc.edu/goes/blog/archives/21307#respondSun, 29 May 2016 21:15:39 +0000http://cimss.ssec.wisc.edu/goes/blog/?p=21307
GOES-13 6.5 µm Water Vapor Infrared images[click to play animation]
Tropical Depression 2 was upgraded to Tropical Storm Bonnie at 2100 UTC on Saturday 28 May, the second named storm of the 2016 Atlantic Season (Hurricane Alex, which formed in January, was the first named storm). The water vapor animation above shows that Bonnie’s initial spin may be traced to a front associated with an occluded system which crawled through the eastern United States, exiting on about 23 May 2016. It’s not uncommon for vorticity associated with extratropical cyclone fronts to sow the seed of a tropical cyclone, especially early (or late) in the season. In this case, the cold front failed to pass Bermuda, and by 27 May, persistent thunderstorms about halfway between Bermuda and the Bahamas suggested tropical cyclogenesis was underway (GOES-13 visible image animations: 26 May | 27 May).
MIMIC Total Precipitable Water derived from Microwave imagery, 1800 UTC 28 May – 1700 UTC 30 May [click to enlarge]
Total Precipitable Water fields from the microwave MIMIC product, above, show the system was embedded deep within tropical moisture (24-26 May animation). Tropical moisture associated with the storm moved up the east coast of the United States into the mid-Atlantic States with local flooding reported. This longer animation (from 21 through 28 May) shows that persistent westward motion of moisture occurred over the tropical Atlantic well in advance of Bonnie’s formation.
Rapidscat Scatterometer Winds, 1012 UTC on 27 May [click to enlarge]
The tropical wave that produced Bonnie showed a closed circulation as early as 1012 UTC on 27 May according to Rapidscat scatterometer winds, above, and MODIS Sea Surface Temperatures, below, showed very warm water (with SST values of 80º F) over the Gulf Stream.
MODIS-based Sea Surface Temperatures, 1848 UTC on 27 May [click to enlarge]
Suomi NPP VIIRS Day/Night Band (0.70 µm Visible) and Infrared (11.45 µm) Imagery at 0621 UTC on 27 May 2016 [click to enlarge]
Suomi NPP overflew this tropical system at various times during its lifecycle. Shortly after midnight on 27 May 2016, above, strong convection was centered just north of the apparent surface circulation (as inferred by the curved bands of low-level clouds, clouds made visible by moonlight in the night-time VIIRS Day/Night Band visible imagery). Twenty-four hours later, at 0742 UTC on 28 May, below, in a more zoomed-in view, the (then) Tropical Depression Number 2 is supporting strong convection that is obscuring the low-level circulation center.
Suomi NPP VIIRS Day/Night Band (0.70 µm Visible) and Infrared (11.45 µm) Imagery at 0742 UTC on 28 May 2016 [click to enlarge]
Suomi NPP VIIRS Day/Night Band (0.70 µm Visible) and Infrared (11.45 µm) Imagery at 0723 UTC on 29 May 2016 [click to enlarge]
Finally, at 0723 UTC on 29 May, (above) after strong wind shear has displaced all convection well north of the center, the low-level circulation of Tropical Storm Bonnie is southeast of the South Carolina Coast. Strong convection is over North Carolina. This shear was noted in the 0300 UTC and 0900 UTC (29 May) Discussions from the National Hurricane Center. The effect of shear is apparent in the two GOES-13 Infrared Images below, from 2045 UTC on 28 May when convection was close to the center, and from 1045 UTC on 29 May, shortly before landfall, when convection was stripped from the center and displaced well to the north.
GOES-13 Infrared (10.7 µm) Imagery at 2045 UTC on 28 May and at 1045 UTC 29 May 2016; the Yellow Arrow points to the low-level circulation center [click to enlarge]
GOES-13 Visible (0.63 µm) images [click to play MP4 animation]
The remnant circulation of Bonnie moved very slowly northeastward during the 30 May – 01 June period, as seen in GOES-13 Visible (0.63 µm) images covering each of those 3 days (above; also available as a large 95 Mbyte animated GIF). The periodic formation of deep convective clusters continued to produce heavy rainfall over parts of far eastern North and South Carolina.
On the morning of 01 June, an overpass of the Metop-B ASCAT instrument sampled the flow around the low-level circulation center (LLCC) off the coast of North Carolina; several hours later, Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images provided a high-resolution view of the system at 1755 UTC (below). Cloud-top IR brightness temperatures were as cold as -78º C within the small convective cluster located just north of the LLCC.
Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]