GOES-13 visible (0.63 µm) images (above; click image to play animation; also available as an MP4 movie file) revealed a large amount of ice remaining in southern and eastern portions of Hudson Bay, Canada on 07 August 2015. The ice can be seen “sloshing” back and forth during the day as winds and/or water currents moved it around.

The discrimination of ice vs supercooled water droplet clouds can be made by comparing Terra MODIS true-color and false-color Red/Green/Blue (RGB) images at 1611 UTC (below). On the false-color image, ice (and glaciated clouds with a high concentration of ice crystals at cloud top) appeared as darker shades of red, in contrast to supercooled water droplet clouds which appeared as varying shades of white to cyan.

A Suomi NPP VIIRS true-color image as visualized using the SSEC RealEarth web map server (below) showed the ice at 1800 UTC; even greater detail can be seen in this zoomed-in version of the image.

Maps from from the Canadian Ice Service (below) indicated that the concentration of this thick first-year ice (dark green) was still as high as 9/10ths to 10/10ths (red) on 07 August; on 03 August, the ice concentration departure from normal was as high as +9/10ths to +10/10ths (dark blue) in some locations.

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A sequence of 10-minute interval Himawari-8 true-color Red/Green/Blue (RGB) images covering the period 01 August to 06 August 2015 is shown above (also available as a very large 721 MByte animated GIF, a 66 Mbyte MP4 movie file, or an alternate version here on YouTube). One of the most prominent features seen is Typhoon Soudelor in the West Pacific Ocean, which reached Category 5 Super Typhoon intensity late in the day on 03 August, as indicated in a plot of the Advanced Dvorak Technique intensity estimate from the CIMSS Tropical Cyclones site (below).

Other features of interest seen during this 6-day animation include hazy-white plumes of urban pollution and/or wildfire smoke streaming eastward off the Asian continent, as well as light brown or tan-colored plumes of blowing dust/sand originating from the interior desert regions.

The Himawari-8 AHI data are provided by the JMA, acquired by NOAA/NESDIS/STAR, and processed at SSEC/CIMSS. The true-color images use information from AHI bands 1, 2, and 3, combined with a customized contrast stretch algorithm. No background image was used.

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The animation above (link) shows two-plus days of 10.35 µm Infrared imagery (from Himawari-8) of Typhoon Soudelor over the western Pacific Ocean. The animation of 2.5-minute interval images is from the Himawari-8 Target Sector that shifts as the Typhoon moves. The animation shows significant strengthening to Category 5 intensity and subsequent weakening as the storm undergoes an eyewall replacement cycle (ERC). That ERC is apparent in the MIMIC morphed microwave imagery, below. In addition, an SST Analysis from the CIMSS Tropical Cyclones site shows the storm traversing an area of relatively cooler Sea Surface Temperatures. Strengthening is expected in the next days as the storm approaches Taiwan.

A visible animation (0.52 µm, 2.5-minute time steps) from Himawari-8, below, (available here as an mp4, or here on YouTube) during the day on 4 August, shows a relatively clear eye with embedded vortices. In addition, tranverse banding at the cirrus level is obvious.

Suomi NPP overflew Soudelor during the night on 4 August. The toggle between the VIIRS Day/Night Band visible (0.70 µm) image and the Infrared (11.45 µm) image is shown below (courtesy William Straka, SSEC). The three-quarter full moon supplied ample illumination to yield a very crisp visible image at night.

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After a July with rainfall that was significantly above normal (Link), Tampa experienced heavy rain on both August 1st and August 3rd, leading to flooding conditions. The animation of Total Precipitable Water, above, from 2-4 August, shows the moisture-rich environment in which the showers and thunderstorms developed. Tampa appears to be in a corridor of moisture transport between tropical easterlies over the Atlantic and more westerly motion in advance of a surface trough that had sagged into the northern Gulf of Mexico. As a result of the rains (3.89″ on 1 August and 4.39″ on 3 August), Flood Warnings and Flood Watches persist on 4 August, and River Gauges (Source: http://water.weather.gov/ahps/index.php) continue to show conditions above flood stage (below).

GOES-13 Imagery, below, captured the evolution of the heavy rains on 1 August (Loop available here as mp4). These rains fell mostly during the day, and satellite data suggests training convection (that is, repeated development of thunderstorms over one region) produced the rain.

Visible imagery (Click here for mp4) during the day on 1 August (above) confirm the training nature of the convection over Tampa.

In contrast, the heavy rains early on 3 August were associated with a strong mesoscale convective system (loop shown below, or available here as mp4) that developed over the northeast Gulf of Mexico and then sagged southward over Tampa.

The toggle below of 11.45 µm Brightness Temperature and Day Night band visible (0.70 µm) imagery from 0751 UTC on 3 August shows very cold overshooting tops with temperatures as cold as -88 C over the northwest Gulf. Transverse banding around the periphery of the system is also apparent. Such bands are a signal of turbulence (although no reports were issued at that time).

How much rain has fallen in the week ending 4 August 2015? The image below, from this site, shows totals exceeding 10″ just north of Tampa.

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