GOES-17 (GOES-West) Mid-level Water Vapor (6.9 µm) and Air Mass RGB images — with and without contours of RAP40 model PV1.5 pressure — (above) displayed a shear vortex moving southeastward toward the coast of California on 09 March 2022. These vortices frequently perturb the local “dynamic tropopause” (represented by the PV1.5 pressure), drawing it down to lower altitudes (as was seen here and here).

A Mid Level Wind Shear product from the CIMSS Tropical Cyclones site (below) showed that this satellite feature had developed along a tight gradient of wind shear off the California coast. Occasionally such shear gradient vortices can produce turbulence that affects aircraft, as was seen in this example.

View only this post Read Less

GOES-16 (GOES-East) Shortwave Infrared (3.9 µm), Fire Temperature RGB. Fire Temperature and Fire Power products (above) displayed signatures of the large Bertha Swamp Road Fire and a smaller Adkins Avenue Fire near Panama City in the Florida Panhandle on 06 March 2022. With the Bertha Swamp Road Fire, 3.9 µm Shortwave Infrared brightness temperatures reached 138.71ºC — the saturation temperature of ABI Band 7 detectors — the derived Fire Temperature maximum value was 2287.24 K, and Fire Power values peaked at 1440 MW. The Fire Temperature and Fire Power derived products are components of the GOES Fire Detection and Characterization Algorithm FDCA.

GOES-16 True Color RGB images created using Geo2Grid (below) showed smoke-laden pyrocumulus clouds (created by the very hot Bertha Swamp Road Fire), which rose above the level of boundary layer cumulus cloud streets that were moving inland across the area.

These fires were occurring in an area affected by the landfall of Hurricane Michael in 2018 — where a large amount of downed trees (within the shades of tan to light brown shown below on 18 October 2018) still remained. Both fires were located near the center of the MODIS images.

===== 07 March Update =====

On 08 March, increasing surface wind speeds led to a consolidation of fires to form the Chipola Complex — and GOES-16 Shortwave Infrared, Fire Temperature RGB, Fire Temperature and Fire Power (above) indicated that this fire complex was centered in far southwestern Calhoun County, Florida.  Clouds often partially obscured a clear view of the entire fire, but the 3.9 µm Shortwave Infrared brightness temperatures reached 135.91ºC, the derived Fire Temperature maximum value was 1649 K, and Fire Power values peaked at 2121 MW.

GOES-16 True Color RGB images (below) again showed some pyrocumulus clouds near the fire source, with a larger smoke plume that extended well into southwestern Georgia. 

View only this post Read Less

The animation above shows a progression of mid-tropospheric lapse rates between late on 4 March and late on 6 March 2022. The purple circles enclose regions of steep mid-level lapse rates; dotted purple circles show the location of the steep mid-level lapse rates in the previous image. This slow animation shows the progression of these steep lapse rates towards late-afternoon tornadic outbreaks, shown as the inset Storm Reports (5 March 2022 ; 6 March 2022) from the Storm Prediction Center.

Are the steep lapse rates picking up on Elevated Mixed Layers? Compare the NUCAPS plot at 0830 UTC on 5 March and the adjacent Skew-T from Dodge City Kansas at 1200 UTC on the 5th, shown below; or the NUCAPS plot from 0830 UTC on 6 March and the adjacent Skew-T from Amarillo at 1200 UTC on the 6th, shown at the bottom.

Consider viewing gridded NUCAPS estimates of Lapse Rates every morning as part of your situational awareness to determine whether an Elevated Mixed Layer might influence subsequent weather. Gridded NUCAPS fields are available here (A NASA SPoRT site) and here (a RealEarth site).

Many thanks to Chris Gitro, MIC at WFO Duluth, for discussions about this case!

View only this post Read Less

SPC (The Storm Prediction Center) issued a Convective Outlooks on 5 March 2022 (1630 UTC; 2000 UTC) showing an Enhanced Risk of Severe Weather over portions of southern Iowa. Preliminary Storm Reports for the day (link) showed tornadoes south of a line from southwestern Iowa to near Des Moines, starting near 2100 UTC. The animation above shows the Day Cloud Phase Distinction RGB and the derive Lifted Index as very strong convection (ultimately tornadic) develops over southwestern Iowa in a region where Lifted Index values are near -4.

NOAA-20 overflew the region of convective initiation at around 1930 UTC. Mid-tropospheric lapse rates (700-500 mb) are below. The stability diagnosis shows an unstable atmosphere. A diagnosis of the Total Totals index shows very large values — >50 — over southwestern Iowa and eastern Kansas. Convection in this airmass is likely to be strong.

The instability over eastern Kansas was also measured with a special radionsonde launch from Topeka at 2000 UTC, and that radiosonde is compared to a NUCAPS profile (close to Topeka in space and in time) below. Some aspects of the two profiles are similar.

What do other NUCAPS profiles look like over Iowa? The image below shows NUCAPS sounding availability points, and also 3 profiles at the points indicated. Steepest mid-tropospheric lapse rates are in the southern part of the domain. Recall that tornadoes were south of a line from the southwest corner of Iowa to Des Moines.

---

Legacy Atmospheric Profiles from GOES-16 are available at points, and a benefit is that they are produced every 30 minutes, so that changes in atmospheric stability with time can be monitored. (This profiling capability will be greatly enhanced with the sounder instrument scheduled to fly on GEO-XO). The single profile above documents a very steep mid-tropospheric lapse rate just to the south of Des Moines. That same profile (2051 UTC) and one at the same point 30 minutes later (2121 UTC) are shown below.

1-minute @NOAASatellites #GOES16/#GOESeast Visible images with time-matched plots of SPC Storm Reports show the daytime portion of today's outbreak of tornadoes across Iowa: https://t.co/moafbzYpn9 #IAwx @NWSOmaha @NWSDesMoines pic.twitter.com/f5iZ5WkOXt

— Scott Bachmeier (@CIMSS_Satellite) March 6, 2022

---

AWIPS imagery in this blog post was created using the NOAA/NESDIS TOWR-S AWIPS Cloud Instance.

View only this post Read Less