Using NUCAPS profiles before Pyrocumulus events

September 11th, 2022 |
GOES-17 True-color imagery, 2101 UTC 10 September to 0106 UTC on 11 September

A CSPP Geosphere mp4 animation from late on 10 September, above (link), shows the development of a pyrocumulus cloud at the south edge of the Cedar Creek fire complex in Oregon (previously discussed here, here and here). The animation above starts at 2101 UTC, shortly after a NOAA-20 overpass above the region. NUCAPS profiles over the regions can define the thermodynamics to help forecasters determine is pyrocumulus clouds might develop. The Green points in the sounding availability plots, below, denote retrievals that converged to a solution using both microwave and infrared data from the ATMS and CrIS instruments, respectively. This includes the profiles near the very warm Cedar Creek fire pixels in east-central Oregon. (Here is a zoomed-in view over the fire with GOES-17 FDCA Fire Power observations; note the two different regions of active fire).

GOES-17 Band 7 (3.9 µm) imagery at 2020 UTC on 10 September 2022 along with NUCAPS Sounding Availability plots (Click to enlarge)

The animation below steps through 3 NUCAPS profiles near the fire. A dry atmosphere is apparent, but note also the very steep lapse rates. If convection develops, aided by the heat of the fire, there is little to inhibit its growth to the tropopause.

NUCAPS profiles east, over and west of the Cedar Creek fire, ca. 2050 UTC on 10 September 2022 (Click to enlarge)

NUCAPS profiles can be gridded to provide horizontal fields of thermodynamic variables. The lapse rate computed from 850 and 500 mb temperatures, below, also shows very steep lapse rates (note that portions of Oregon are at/above 850 mb and no data are available).

GOES-17 Band 7 (3.9 µm) imagery along with NUCAPS gridded lapse rates (850-500 mb), ca. 2030 UTC on 10 September 2022 (Click to enlarge)

One things that happens when a Pyrocumulus develops: the cloud is trackable (in contrast to any surrounding smoke). The CSPP Geosphere animation below (link) shows the Night Microphysics (at night) and True-Color (during the day) — the cloud can be tracked until is dissipates near dawn, and the true-color imagery the next day shows the smoke associated with the pyrocumulus has also moved to the east. Note also in the animation how the active fires show up in the GOES-17 Night Microphysics as different shades of magenta.

Hourly imagery from CSPP Geosphere, 2206 10 September 2022 – 1706 UTC on 11 September 2022

Although infrared imagery is challenged to view smoke at night, as suggested in the animation above, the VIIRS Day Night band sees it (if there is sufficient illumination by the Moon). That was the case early on 11 September, as shown below (in an image taken from the VIIRS Today website). Both the light signature from fires are apparent as is the smoke plume from the pyrocumulus.

NOAA-20 Day Night Band visible (0.7 µm) imagery over Oregon, ca. 1100 UTC on 11 September 2022 (click to enlarge)

AWIPS Satellite imagery in this blog post were created using the TOWR-S AWIPS. Thank you!

CSPP Geosphere views of smoke in Oregon and Idaho

September 9th, 2022 |
GOES-West True-Color imagery, 1506-1911 UTC on 9 September 2022

CSPP Geosphere animations from GOES-West (above, link) and GOES-East (below, link) both show an active fire — the Cedar Creek fire — over Oregon (previously discussed here). Low-level winds (as shown in the 1200 UTC sounding from Medford OR) are moving the smoke plume out over the Pacific Ocean. The oblique side-view from GOES-East (below) gives a better view of the structure of the smoke plume.

CSPP Geosphere GOES-East view over Oregon, 1506 – 1911 UTC on 9 September 2022

Later in the day, a brief pyrocumulus jump ejected smoke to higher altitudes, where westerly winds prevailed:

Fires over Idaho are also producing smoke that has been trapped in valleys, as shown below. Much of Idaho is under an Air Quality Alert (link). A current map of Air Quality can be viewed here. The image from 2000 UTC on 9 September is here.

GOES-West True-Color image from CSPP Geosphere, 1506 UTC on 9 September 2022 (Click to enlarge)

Blowing dust and wildfire smoke in northern Argentina

August 15th, 2022 |

GOES-16 True Color RGB and Nighttime Microphysics RGB images [click to play MP4 animation]

GOES-16 (GOES-East) True Color RGB and Nighttime Microphysics RGB images from the CSPP GeoSphere site (above) showed an arc of blowing dust (along with multiple wildfire smoke plumes) moving northward across northern Argentina — behind a cold front — on 15 August 2022.

Embedded within the broad arc of blowing dust were dense plumes originating from salt flats along the northern edge of Mar Chiquita Lagoon — a closer view of those plumes is shown below.

GOES-16 True Color RGB images [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm) images (below) include plots of hourly surface reports — and as the cold front moved northward, surface report data (SACO | SANT | SARC | SARF | SASA | SASJ) revealed southerly wind gusts as high as 34 knots and visibility restrictions as low as 3 miles (due to blowing dust) along/behind the front.

GOES-16 “Red” Visible (0.64 µm) images [click to play animated GIF | MP4]

Saharan Air Layer dust reaches the Southeast US coast

August 10th, 2022 |

GOES-16 True Color RGB images, from 1130-2250 UTC on 08 August, 09 August and 10 August [click to play animated GIF | MP4]

GOES-16 (GOES-East) True Color RGB images created using Geo2Grid (above) covered the daytime period from 1130-2250 UTC on 08 August, 09 August and 10 August 2022 — and displayed the hazy signature of Saaran Air Layer (SAL) dust as it approached the Southeast US coast (Florida, Georgia and South Carolina in particular). This hazy dust signature was more pronounced early and late in the day, when the forward scattering of light was more pronounced (due to a lower usun angle).

The GOES-16 Aerosol Optical Depth (AOD) derived product (below) provided a quantitative measure of the density of this dust — with AOD values generally ranging from 0.5 to 0.8. Note the westward-moving semicircular region where no AOD appears every day: these are areas where the product is not created, due to contamination by sun glint off the water.

GOES-16 Aerosol Optical Depth derived product, from 1110-2230 UTC on 08 August, 09 August and 10 August [click to play animated GIF | MP4]

GOES-16 Split Window Difference SAL product images (source) covering the 8-day period from 03-10 August (below) showed the westward transport of this SAL dust across the Atlantic Ocean.

GOES-16 Split Window Difference SAL product, from 03-10 August [click to play animated GIF | MP4]

Some of this airborne SAL dust subsided into the boundary layer, occasionally reducing the surface visibility to 5-7 miles at a few sites near and along the coast in Florida (KSGJ, KJAX, KFHB, K42J), Georgia (KSSI, KJES) and South Carolina (KJZI, KARW).