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ACSPO SSTs over Lake Michigan and over the Pacific Ocean

The animation above shows ACSPO estimates of Lake Surface Temperature (LST) over Lake Michigan from 3 different VIIRS overpasses: NPP at 0703 and 0844, and NOAA-20 at 0753 UTC (despite the AWIPS label!) early on 18 July 2022; VIIRS data were downloaded at the CIMSS Direct Broadcast antennae, and ACSPO... Read More

VIIRS ACSPO SSTs, 0703, 0753 and 0844 UTC on 18 July 2022, along with buoy observations (Click to enlarge)

The animation above shows ACSPO estimates of Lake Surface Temperature (LST) over Lake Michigan from 3 different VIIRS overpasses: NPP at 0703 and 0844, and NOAA-20 at 0753 UTC (despite the AWIPS label!) early on 18 July 2022; VIIRS data were downloaded at the CIMSS Direct Broadcast antennae, and ACSPO SST fields were created using CSPP software; AWIPS-ready tiles are available via an LDM feed from CIMSS. Orange to red enhancement values show lake surface temperature at/above 20oC/68oF (the color bar limits are 41oF/77oF). Two NOAA buoys are also present within Lake Michigan, and both show lake temperatures of 69oF; satellite values show far greater variability within the lake than can be deduced from just two buoy-based observations.

GOES-R data are used to create lake-surface (and sea-surface) temperatures. The toggle below over Green Bay and central Lake Michigan shows the superior spatial resolution of the VIIRS instrument. Over the open lake, GOES-R SSTs run about 1/2oF warmer than SSTs from VIIRS.

GOES-16 and VIIRS SST estimates over Green Bay and central Lake Michigan, ca. 0900 UTC on 18 July 2022 (click to enlarge)

Similar imagery (also using Direct Broadcast data and created using CSPP software) was available slightly later off the coast of Oregon, as shown below. Three consecutive passes of VIIRS, at about 45-minute intervals, allow for changes in the surface temperature fields to be monitored with high spatial and temporal resolution.

VIIRS ACSPO SSTs, 0934, 1026 and 1118 UTC on 18 July 2022 (Click to enlarge)

ACSPO SST (and individual channel, and true/false color) imagery is routinely available at the CIMSS direct broadcast site at this link for NOAA-20 and this link for NPP. You can also find True Color imagery over the Great Lakes, such as the image below from NOAA-20, posted for your viewing pleasure.

NOAA-20 True-Color imagery over the Great Lakes, 1850 UTC on 14 July 2022 (Click to enlarge)

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Mesoscale Convective Vortex over southern Nevada

GOES-18 images shown in this blog post are preliminary and non-operational Overlapping 1-minute Mesoscale Sectors provided 30-second images of GOES-18 “Red” Visible (0.64 µm) data, which showed the circulation of a Mesoscale Convective Vortex (MCV) that moved northward across southern Nevada early in the day on 17 July 2022. Ongoing thunderstorms along the periphery... Read More

GOES-18 “Red” Visible (0.6.4 .µm) images [click to play animated GIF | MP4]

GOES-18 images shown in this blog post are preliminary and non-operational

Overlapping 1-minute Mesoscale Sectors provided 30-second images of GOES-18 “Red” Visible (0.64 µm) data, which showed the circulation of a Mesoscale Convective Vortex (MCV) that moved northward across southern Nevada early in the day on 17 July 2022. Ongoing thunderstorms along the periphery of this MCV slowly dissipated as they moved across California and Nevada — and according the morning NWS Las Vegas forecast discussion, some of these storms produced rare July rainfall in parts of Death Valley, California.

According to NAM40 model winds, this MCV was moving through an environment of generally low wind shear (below), where there was also sufficient moisture and instability.

GOES-17 “Red” Visible (0.6.4 .µm) image, with plots of NAM40 model 850 hPa and 500 hPa wind barbs [click to enlarge]

The GOES-18 Total Precipitable Water (source) derived product (below) also showed abundant moisture across much of the Desert Southwest as the MCV approached — which helped to sustain the MCV as it moved across southern Nevada.

GOES-18 Total Precipitable Water derived product [click to play animated GIF | MP4]

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Himawari-8 and NUCAPS observations of an upper-level feature in the western Pacific

Himawari-8 Imagery, above (courtesy JMA, the Japan Meteorological Agency, from this site), shows a cyclonically rotating feature over the western Pacific, approaching the northern Marianas Islands by the end of the animation. Periodic weak convection is forming within the center of the circulation, with more widespread convection developing to its east.... Read More

ABI Sandwich Product (Day TIme) and Band 13 (10.41 µm, night time) from 0000 UTC on 10 July 2022 through 2350 UTC on 12 July 2022 (Click to enlarge)

Himawari-8 Imagery, above (courtesy JMA, the Japan Meteorological Agency, from this site), shows a cyclonically rotating feature over the western Pacific, approaching the northern Marianas Islands by the end of the animation. Periodic weak convection is forming within the center of the circulation, with more widespread convection developing to its east. Gridded NUCAPS fields, below, from this site, show that the cyclonic feature is associated with relatively cool temperatures at 500 mb. At the beginning of the animation, the cool temperatures are near Wake Island; the cool temperatures progress steadily westward just south of 20o N latitude over the following days and are over the Marianas at the end of the animation.

Gridded NUCAPS estimates of 500-mb temperatures, 09-13 July 2022 (click to enlarge)

Examination of surface-based winds (from scatterometers, at this site) suggests that the mid-level circulation does not extend all the way to the surface.


Update, 14 July 2022

By 0333 UTC on 14 July 2022, the cool region at 500 mb was centered just west of 20oN, 150oE. (Its westward progress has slowed significantly) The cool region overlaps a ‘green’ Quality Control Region, meaning the retrieval there converged to a solution. Yellow regions likely correspond with clouds, and the infrared retrieval did not converge (but the microwave one did); red points depict a lack of convergence in the infrared and microwave retrievals. For more information on the retrieval, check out this training video on NUCAPS profiles.

Gridded NUCAPS field of 500-mb Temperature, and NUCAPS Quality Control Flag, 0333 UTC on 17 July 2022 (Click to enlarge)

Did the cold pool aloft have a surface signature? Scatterometry overlain on top of Himawari-8 Visible (0.64 µm) imagery, along with a streamline analysis from the NOAA/NWS/NCEP Global Forecasting System (GFS) model, shown below (courtesy Brandon Aydlett, WFO Guam), shows anticyclonic flow underneath the region of the upper-level cold pool. Upper-level (300-mb) streamline (shown here overlain on top of Himawari-8 Upper Level water vapor imagery (Band 8, 6.24 µm), also courtesy Brandon Aydlett) shows an upper-level cyclonic circulation associated with the cold pool.

Himawari-8 Visible Imagery (0.64 µm) at 0140 UTC, ASCAT observations (0130-0300 UTC), and GFS Surface Streamlines (3-h forecast valid 0300 UTC), all on 14 July 2022 (click to enlarge)

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Pyrocumulonimbus cloud in northwestern Canada

1-minute Mesoscale Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.35 µm) and Fire Temperature RGB images (above) showed a wildfire just southwest of Yellowknife (CYZF) in Canada’s Northwest Territories, which produced a pyrocumulonimbus (pyroCb) cloud during the afternoon hours on 12 July 2022.This large fire burned very hot,... Read More

GOES-17 “Red” Visible (0.64 µm, top left), Shortwave Infrared (3.9 µm, top right), “Clean” Infrared Window (10.35 µm, bottom left) and Fire Temperature RGB (bottom right) images [click to play animated GIF | MP4]

1-minute Mesoscale Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), “Clean” Infrared Window (10.35 µm) and Fire Temperature RGB images (above) showed a wildfire just southwest of Yellowknife (CYZF) in Canada’s Northwest Territories, which produced a pyrocumulonimbus (pyroCb) cloud during the afternoon hours on 12 July 2022.

This large fire burned very hot, with 3.9 µm Shortwave Infrared brightness temperatures reaching 138.71ºC — which is the saturation temperature of ABI Band 7 detectors. The coldest pyroCb cloud-top 10.35 µm Infrared Window brightness temperatures were around -49ºC (lighter shades of blue).

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