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).
———————————————————————————————————-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.
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).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. 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.
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.
Although the storm produced a funnel cloud (prompting the issuance of Canada’s first tornado warning of 2016):
— The Weather Network (@weathernetwork) June 10, 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.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).