Meteosat-10 0.75 µm visible channel and 10.8 µm IR channel images (click to play animation)

Twitter follower @PedroCFernandez alerted us to an interesting case of mesovortices (original Spanish language blog post | Google translate version) which developed within the circulation of a strong mid-latitude cyclone over the northeastern Atlantic Ocean (moving toward the British Isles) on 24-25 February 2014. McIDAS images of EUMETSAT Meteosat-10 daytime 0.75 µm high resolution visible channel and night-time 10.8 µm IR channel data (above; click to play animation) revealed the series of mesovortices that spun up along the “bent-back” occluded frontal boundary (surface analyses); this storm was producing hurricane force winds during the 12-18 UTC period on 24 February, according to the NWS Ocean Prediction Center. Mesovortex cloud-top IR brightness temperatures were around -40º C (green color enhancement), indicating significant vertical development of the cloud structure associated with these features.

Meteosat-10 0.75 µm visible channel and 10.8 µm IR channel images at 18:00 UTC

A comparison of the 18:00 UTC Meteosat-10 visible and IR images (above) showed two well-developed mesovortices at that time: #1, located southwest of the storm center, and #2, located west of the storm center;  a new mesovortex #3 was just in the process of forming to the northwest of the storm center (below).

Meteosat-10 10.8 µm IR channel image at 18:00 UTC

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GOES-15 0.63 µm visible channel images (click to play animation)

Hat-tip to Matt Sitkowski and Carl Parker of The Weather Channel for the heads-up on some interesting wave features that could be seen in the vicinity of Guadalupe Island on McIDAS images of GOES-15 0.63 µm visible channel data (above; click image to play animation) on 24 February 2014. Apparently a gravity wave had propagated northwestward through the region during the morning hours, perturbing the depth of the marine boundary layer (MBL) such that undulations in the MBL stratocumulus clouds were quite evident. In addition, an unusual “dry pulse” propagated outward from Guadalupe Island (located in the center of the images). These wave features eventually became hidden as layers of middle and high clouds overspread the area from the southwest.

AWIPS images of GOES-15 0.63 µm visible channel data with overlays of Real-Time Mesoscale Analysis (RTMA) surface winds (below) showed that the surface flow was very light or even calm across much of the Guadalupe Island region during the time that the “dry pulse” was most evident on visible imagery.

GOES-15 0.63 µm visible images with RTMA surface winds

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Suomi NPP VIIRS 1.38 µm near-infrared imagery (M09), 1736 UTC 21 February   2014 (click image to enlarge)

A strong late-winter cyclone brought significant snows and blizzard conditions to the upper Great Lakes/northern Plains on 21 February 2014 (NWS storm summaries: MPX | DLH | ARX). In the warm sector of the storm, there were numerous reports of tornadoes, large hail, and damaging winds in the eastern US. Suomi NPP viewed the storm multiple times, including just before 1800 UTC on 21 February.

The Suomi NPP VIIRS 1.38 µm imagery, above, was created using CSPP and highlights cirrus-level clouds, documenting just how widespread the canopy of this extratropical cyclone was (more imagery is available via ftp, and a description of the various bands is available here).

Suomi NPP VIIRS I1, Day/Night, I3, I4, I5 bands at 1736 UTC 21 February 2014 (click image to enlarge)

VIIRS imagery (375-meter resolution I-bands 1, 3, 4, and 5, along with the 750-meter resolution Day/Night Band) is available in AWIPS via an LDM subscription. The animation above cycles through these different bands as displayed using AWIPS: Visible (0.64 µm), Day/Night Band (0.70 µm), Snow/Ice Channel (1.61 µm), Shortwave IR (3.74 µm) and IR Window (11.45 µm) channels.

VIIRS 750-meter resolution M-bands can be used to create true-color imagery: the example from 1736 UTC is shown below.

Suomi NPP VIIRS True-color imagery, 1736 UTC 21 February 2014 (click image to enlarge)

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GOES-13 0.63 µm visible channel images (click to play animation)

A GOES-13 (GOES-East) North/South Station Keeping maneuver was performed on Wednesday, February 19, 2014, beginning 1145 UTC, and ending at 1945 UTC (Link). During this time, the navigation of the satellite degraded mostly in the north-south direction. At 1945 UTC, after the maneuver ended, the navigation snapped back to normal. (Compare the 1932 and 1945 UTC images).

Navigation error tracking is available online for some geostationary satellites. For example, this link, off this page, shows landmark errors from MTSAT. NOAA’s OSPO maintains a site for GOES satellites; however, results are posted weekly. (Link).

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