This website works best with a newer web browser such as Chrome, Firefox, Safari or Microsoft Edge. Internet Explorer is not supported by this website.

CIMSS Satellite Blog

MENU

NUCAPS Sounding profiles surrounding Colorado’s East Troublesome Fire

By Scott Lindstrom •

The East Troublesome Fire in Colorado expanded greatly on 21 October (click here for more information), and produced pyrocumulus clouds.  NOAA-20 overflew the fire at around 1930 UTC (linked-to overpass map from this site) on 21 October, and NUCAPS profiles, shown above, diagnosed the stability of the mid- and upper-troposphere.  The toggle below between the NOAA-20 VIIRS Visible (0.64 µm) and Infrared (11.45 µm) imagery and NUCAPS Sounding availability... Read More

NOAA-20 NUCAPS Profiles over Colorado, at locations indicated, at ca. 1900 UTC on 21 October 2020 (click to enlarge)

The East Troublesome Fire in Colorado expanded greatly on 21 October (click here for more information), and produced pyrocumulus clouds.  NOAA-20 overflew the fire at around 1930 UTC (linked-to overpass map from this site) on 21 October, and NUCAPS profiles, shown above, diagnosed the stability of the mid- and upper-troposphere.  The toggle below between the NOAA-20 VIIRS Visible (0.64 µm) and Infrared (11.45 µm) imagery and NUCAPS Sounding availability points show the relationships between cloudiness and point color.

Suomi NPP Visible (0.64 µm) and Infrared (11.45 µm) imagery at 2015 UTC on 21 October 2020, as well as (NOAA-20) NUCAPS Sounding availability points at ~1900 UTC on 21 October (Click to enlarge)

Gridded NUCAPS fields, below, of 500-300 mb lapse rates show very weak stability in and around the fire location.  A fire-driven updrafts in the region would not find much in the way to impede its vertical development.

NUCAPS estimates of upper-tropospheric (500-300 mb) lapse rates at ca. 1900 UTC on 21 October 2020 (Click to enlarge)

View only this post Read Less

Blowing dust from the Copper River Delta in south-central Alaska

By Scott Bachmeier •

Strong gap winds accelerating out of the Copper River Valley along the southern coast of Alaska were lofting fine particles of glacial silt/sand and transporting those aerosols southward across the Gulf of Alaska on 20 October 2020. 1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Dust Red-Green-Blue (RGB) images (above) displayed the plume... Read More

GOES-17

GOES-17 “Red” Visible (0.64 µm) and Dust RGB images [click to play animation | MP4]

Strong gap winds accelerating out of the Copper River Valley along the southern coast of Alaska were lofting fine particles of glacial silt/sand and transporting those aerosols southward across the Gulf of Alaska on 20 October 2020. 1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Dust Red-Green-Blue (RGB) images (above) displayed the plume of airborne dust during the period of 1700-2300 UTC.

A good visualization of the dust plume was provided by GOES-17 True Color RGB images created using Geo2Grid (below).

GOES-17 True Color RGB images [click to play animation | MP4]

GOES-17 True Color RGB images [click to play animation | MP4]

A comparison of Suomi NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images at 2040 UTC is shown below — note that the dust plume appeared warmer (darker shades of gray) on the Shortwave Infrared image, since the small dust particles were efficient reflectors of incoming solar radiation.

Suomi NPP VIIRS Visible, Shortwave Infrared and Infrared Window images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]

The dust plume also exhibited a good signature in the VIIRS Aerosol Optical Thickness (AOT) product from the eIDEA-AK site (below).

VIIRS True Color RGB and Aerosol Optical Thickness images [click to enlarge]

VIIRS True Color RGB and Aerosol Optical Thickness images [click to enlarge]

View only this post Read Less

Thundersnow in South Dakota and Minnesota

By Scott Bachmeier •

GOES-16 (GOES-East) Day Cloud Phase Distinction Red-Green-Blue (RGB) images with a overlay of GLM Flash Extent Density (above) displayed clusters of convection — some with brief bursts of lightning activity — which were moving eastward and enhancing snowfall rates from Watertown, South Dakota (station identifier KATY) into far western Minnesota on 20 October 2020. The resulting snowfall amounts... Read More

GOES-16 Day Cloud Phase Distinction RGB images, with an overlay of GLM Flash Extent Density [click to play animation | MP4]

GOES-16 Day Cloud Phase Distinction RGB images, with an overlay of GLM Flash Extent Density [click to play animation | MP4]

GOES-16 (GOES-East) Day Cloud Phase Distinction Red-Green-Blue (RGB) images with a overlay of GLM Flash Extent Density (above) displayed clusters of convection — some with brief bursts of lightning activity — which were moving eastward and enhancing snowfall rates from Watertown, South Dakota (station identifier KATY) into far western Minnesota on 20 October 2020. The resulting snowfall amounts included 6.0 inches near Watertown and 8.0 inches near Ortonville, Minnesota.

View only this post Read Less

Tropical Storm Epsilon in the Atlantic

By Scott Bachmeier •

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed Tropical Depression 27 as further intensified to become Tropical Storm Epsilon at 15 UTC on 19 October 2020. While the low-level circulation (LLC) generally remained exposed during that time, deep convection was increasing around the LLC (including a small convective burst near the... Read More

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed Tropical Depression 27 as further intensified to become Tropical Storm Epsilon at 15 UTC on 19 October 2020. While the low-level circulation (LLC) generally remained exposed during that time, deep convection was increasing around the LLC (including a small convective burst near the storm center forming around 1630 UTC).

GOES-16 Visible image with plots of available NUCAPS profiles [click to enlarge]

GOES-16 Visible image with plots of available NUCAPS profiles [click to enlarge]

A GOES-16 Visible image with plots of available NOAA-20 NUCAPS profiles (above) showed one valid infrared (CrIS) + microwave (ATMS) sounding (green dot) just southeast of the center of Epsilon at 1640 UTC — that sounding profile (below) revealed a moist (PW = 1.95″) and unstable (MU CAPE = 1066 J/kg, and LI = -3) atmosphere just after the time of development of the convective burst near Epsilon’s center.

NUCAPS profile just southeast of the center of Tropical Storm Epsilon [click to enlarge]

NUCAPS profile just southeast of the center of Tropical Storm Epsilon [click to enlarge]

GOES-16 Visible images with overlays of deep-layer wind shear and GLM Flashes from the CIMSS Tropical Cyclones site (below) indicated that Epsilon was in an environment of moderate shear, with limited lighting activity near the storm center.

GOES-16 “Red” Visible (0.64 µm) images, with overlays of deep-layer wind shear and GLM Flashes [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) images, with overlays of deep-layer wind shear and GLM Flashes [click to enlarge]

A toggle between the MIMIC Total Precipitable Water and Saharan Air Layer products (below) showed that Epsilon was embedded within a pocket of abundant moisture, with dry air situated to the north and northwest.

MIMIC Total Precipitable Water and Saharan Air Layer product [click to enlarge]

MIMIC Total Precipitable Water and Saharan Air Layer product [click to enlarge]

Tropical Storm Epsilon was located over water having Sea Surface Temperature values around 28ºC and a modest Ocean Heat Content (below).

Sea Surface Temperature and Ocean Heat Content [click to enlarge]

Sea Surface Temperature and Ocean Heat Content [click to enlarge]



View only this post Read Less

  • last_page First
  • Last last_page

Search blog