Ice motion in the Great Lakes

February 14th, 2018 |
GOES-16 "Red" Visible (0.64 µm) images, with hourly plots of surface wind barbs in cyan and wind gusts (kn0ts) in red (click to play Animated GIF)

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface wind barbs in cyan and wind gusts (knots) in red (click to play Animated GIF | MP4 also available)

GOES-16 “Red” Visible (0.64 µm) images showed ice motion in the western Great Lakes (above) and the central/eastern Great Lakes (below) on 14 February 2018. A flow of southwesterly winds at the surface was helping to move the lake ice toward the northeast. With increasing winds and a return of warmer air, the ice coverage of Lake Superior, Lake Michigan and Lake Huron had decreased slightly from their seasonal peaks a few days earlier — while the ice coverage for Lake Erie remained neared its seasonal peak. The total ice coverage for the Great Lakes as a whole was 57.9% on this day.

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface wind barbs in cyan and wind gusts (knots) in red (click to play Animated GIF | MP4 also available)

Closer views of southern Lake Michigan and southern Lake Huron are shown below. In Lake Huron, small ice floes can be seen breaking away from the land fast ice.

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface wind barbs in cyan and wind gusts (knots) in red (click to play Animated GIF | MP4 also available)

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of surface wind barbs in cyan and wind gusts (knots) in red (click to play Animated GIF | MP4 also available)

250-meter resolution Terra and Aqua MODIS True-color Red-Green-Blue (RGB) images from the MODIS Today site (below) provided more detailed views of the ice floes in southern Lake Michigan, southern Lake Huron and western Lake Erie. The Aqua satellite overpass was about 90 minutes later than that of Terra.

Terra and Aqua MODIS True-color RGB images of southern Lake Michigan [click to enlarge]

Terra and Aqua MODIS True-color RGB images of southern Lake Michigan [click to enlarge]

Terra and Aqua MODIS True-color RGB images of southern Lake Huron [click to enlarge]

Terra and Aqua MODIS True-color RGB images of southern Lake Huron [click to enlarge]

Terra and Aqua MODIS True-color RGB images of western Lake Erie [click to enlarge]

Terra and Aqua MODIS True-color RGB images of western Lake Erie [click to enlarge]

Temporary transition from Himawari-8 to Himawari-9

February 13th, 2018 |

Himawari-8 and Himawari-9

Himawari-8 and Himawari-9 “Clean” Infrared Window (10.4 µm) images [click to play Animated GIF | MP4 also available]

Himawari-9 temporarily took over for Himawari-8 beginning at 0250 UTC on 13 February 2018, as Himawari-8 underwent a 2-day scheduled maintenance. “Clean” Infrared Window (10.3 µm) images of Category 4 Cyclone Gita in the South Pacific Ocean during the satellite transition is shown above.

Himawari-9 was launched on 02 November 2016.

Cyclone Gita in the South Pacific Ocean

February 12th, 2018 |

Himawari-8

Himawari-8 “Red” Visible (0.64 µm, top) and “Clean” Infrared Window (10.4 µm, bottom) images, with hourly plots of surface reports [click to play Animated GIF | MP4 also available]

Himawari-8 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.4 µm) images (above) showed Cyclone Gita as it moved toward Tonga in the South Pacific Ocean during 11 February – 12 February 2018. The tropical cyclone reached Category 4 intensity (ADT | SATCON) near the end of the animation period.

A longer animation of Himawari-8 Infrared images (below) revealed that the center of Gita moved just south of the main island of Tongatapu. Surface observations from Fua’Amotu (NFTF) ended after 0735 UTC.

Himawari-8

Himawari-8 “Clean” Infrared Window (10.4 µm) images, with hourly surface plots [click to play Animated GIF | MP4 also available]

MIMIC-TC morphed microwave imagery (below) showed that Gita underwent an eyewall replacement cycle after moving to the southwest of Tongatapu — a small eyewall was replaced by a larger eyewall, which was very apparent in DMSP SSMIS Microwave (85 GHz) images at 1533 and 1749 UTC.

MIMIC-TC morphed microwave imagery

MIMIC-TC morphed microwave imagery

Metop ASCAT scatterometer surface winds (below) showed Gita around the time that the storm center was just south of Tongatapu at 0850 UTC.

Metop ASCAT scatterometer surface winds [click to enlarge]

Metop ASCAT scatterometer surface winds [click to enlarge]

Large hail in Argentina

February 8th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, top) and “Clean” Infrared Window (10.3 µm, bottom) images, with hourly surface reports (metric units) for Córdoba, Argentina [click to play animated GIF — MP4 also available]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) showed the development of severe thunderstorms which produced very large hail in Córdoba, Argentina on 08 February 2018. Distinct above-anvil plumes were evident on the Visible imagery, with pulses of overshooting tops exhibiting Infrared brightness temperatures in the -70 to -80ºC range (black to white enhancement). The hail reportedly began around 1930 UTC or 4:30 PM local time.

The above-anvil plumes could also be seen in GOES-16 Near-Infrared “Snow/Ice” (1.61 µm) images (below).

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Snow/Ice” (1.61 µm) images, with hourly surface reports (metric units) for Córdoba, Argentina [click to play animated GIF — MP4 also available]

An Aqua MODIS True-color Red-Green-Blue (RGB) image viewed using RealEarth (below) showed the thunderstorm just west of Córdoba around 1850 UTC.

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

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

According to the Worldview site, the coldest Aqua MODIS cloud-top infrared brightness temperature at that time was -78ºC (below).

Aqua MODIS True-color and Infrared Window (11.0 µm) images [click to enlarge]

Aqua MODIS True-color and Infrared Window (11.0 µm) images [click to enlarge]

A time series plot of surface observations at Córdoba (below) showed the warm temperatures and high dew points prior to the arrival of the thunderstorms; there were a number of hail reports between 19 UTC and 02 UTC (4 PM to 11 PM local time).

Time series of surface observations at Córdoba, Argentina [click to enlarge]

Time series of surface observations at Córdoba, Argentina [click to enlarge]