Aircraft “hole punch” and “distrail” cloud features over Texas

February 12th, 2009 |
GOES-13 visible and 3.9 µm shortwave IR images

GOES-13 visible and 3.9 µm shortwave IR images

We received the following in an email from the  National Weather Service forecast office at Fort Worth, Texas:

Some of our forecasters noted an interesting feature on visible satellite imagery on Thursday, Feb 12, 2009. I would like to get an expert opinion on what was causing the observed features. There was a layer of ~ 15kft altocumulus along with some scattered-broken areas of cirrus.

Excellent question…and we appreciate the heads-up on this event. An animation of GOES-13 visible and 3.9 µm “shortwave IR” images (above; QuickTime animation) showed the evolution of two “hole punch” cloud features that were drifting eastward across northern Texas on 12 February 2009. The first hole punch cloud feature moved just to the north of Dallas/Fort Worth (DFW) around 14:45 UTC, while the second feature moved just south of DFW about an hour later (around 15:45 UTC). In addition, an elongated aircraft dissipation trail (or “distrail”) could be seen to the west of the first hole punch feature (oriented west-to-east on the 14:15 and 14:32 UTC visible images), with a second distrail forming about an hour later (oriented northwest-to-southeast on the 15:15 and 15:32 UTC visible images).

These aircraft “hole punch” and “distrail” cloud features form when an aircraft ascends or descends through a layer of supercooled water droplet cloud, with the engine exhaust causing the droplets to glaciate — the resulting ice crystals then fall toward the ground, creating a visible hole or trail in the cloud layer. Note that there is a subtle “brighter white” signal evident on the GOES-13 3.9 µm shortwave IR images in the area of the hole punch features — this colder signal confirms the idea that the aircraft engine exhaust was causing the supercooled water droplets to glaciate.

A NOAA-17 false color Red/Green/Blue (RGB) composite image using channels 01/02/04 (below) showed the second hole punch cloud as it was moving to the south of DFW at 15:58 UTC. Similar aircraft hole punch and distrail cloud features have been seen in the past: for example, over the southcentral US and also over Wisconsin.

NOAA-17 false color RGB image

NOAA-17 false color RGB image

GOES-13 visible and 10.7 µm IR images

GOES-13 visible and 10.7 µm IR images

GOES-13 10.7 µm IR data (above) showed cloud top brightness temperatures in the -20 to -30º C range (cyan to dark blue color enhancement) over much of the cloud patch where the initial hole punch feature was seen. Rawinsonde data from both Midland and Fort Worth in Texas (below) displayed a moist layer centered around 425 hPa that corresponded to those temperatures — this indicates that the hole punch and distrail features were at a fairly high altitude (around 20,000 feet or so). Dallas/Fort Worth METAR reports listed cloud bases at 15,000 feet during the period.

Midland TX and Fort Worth TX rawinsonde data

Midland TX and Fort Worth TX rawinsonde data

Aircraft “distrails” over the southcentral US

January 29th, 2007 |

GOES-12 visible image

GOES-12 visible channel imagery (above; Java animation) revealed numerous aircraft dissipation trails (otherwise known as “distrails” or “hole punch clouds”) during the day over eastern Texas, northern Louisiana, southern Arkansas, and Mississippi on 29 January 2007. Corresponding GOES-12 10.7 µm InfraRed (IR) imagery showed that cloud top temperatures over that region were generally between -20º and -35º C; as aircraft (likely air traffic to/from Dallas-Fort Worth airport KDFW) penetrated that supercooled cloud layer aloft, they caused the cloud droplets to glaciate and begin to fall out of the cloud (causing the “holes” and “streaks” that were evident on the visible imagery). A higher resolution view of these cloud features is available from the Terra MODIS (sourced from the NASA Rapidfire site) and Aqua MODIS overpasses. The 12 UTC rawinsonde data from Fort Worth, Texas (below) indicated that the likely elevation of the supercooled coud deck was around 25,000 feet or so. Photos of these cloud features can be seen on the MediaLine weather forum, Weather Underground WunderBlog, WKRG (Mobile AL), NASA Earth Observatory , and StormCenter Envirocast sites.
Fort Worth TX rawinsonde report

“Hole punch clouds” and aircraft “distrails”

November 15th, 2006 |

GOES-12 visible and shortwave IR image animation
Some interesting photos of “hole punch clouds” were captured on 15 November 2006 — the photos (which appeared on the 16 November Spaceweather.com site) were were taken at Stevens Point in central Wisconsin. A QuickTime animation of GOES-12 visible channel and 3.9µm shortwave IR images (above) revealed a series of aircraft dissipation trails (or “distrails”) drifting northeastward between Madison and Stevens Point during the day; particles in the aircraft exhaust were acting as ice nuclei, causing any supercooled cloud droplets to glaciate and also helping other existing cloud ice crystals to increase in size — these larger ice crystals then descended under the influence of gravity, creating precipitation-induced “holes” and “streaks” in the cloud layers aloft. A 500-meter resolution Aqua MODIS true color image centered on Madison shows better details of the structure of 2 of the northwest-to-southeast oriented “distrails” that were located north of Madison at the time of the satellite overpass.

Other MODIS images and products that were available on AWIPS included the 1000-meter resolution 3.7µm shortwave IR channel (below); the brighter (colder) curved cloud signature in this image suggests that one of the aircraft had recently made a loop in the area between Madison (KMSN) and Wisconsin Dells (KDLL). It is likely that military jets from Volk Field Air National Guard Base (KVOK) were performing training exercises north of Madison, with the jet exhaust helping to initiate some of the interesting cloud patterns that were visible both on the ground and via satellite.
AWIPS MODIS 3.7µm IR image

Aircraft hole punch and cloud dissipation features over Illinois, Indiana and Ohio

December 21st, 2017 |

Terra MODIS true-color and false-color RGB images [click to enlarge]

Terra MODIS True-color and False-color RGB images [click to enlarge]

A toggle between 250-meter resolution Terra MODIS True-color and False-color Red-Green-Blue (RGB) images from the MODIS Today site (above) revealed numerous aircraft “hole punch” and dissipation trail or “distrail” features over Illinois, Indiana and Ohio on 21 December 2017.  These cloud features were caused by aircraft that were either ascending or descending through a layer of cloud composed of supercooled water droplets — cooling from wake turbulence (reference) and/or particles from the jet engine exhaust acting as ice condensation nuclei causes the small supercooled water droplets to turn into larger ice crystals (many of which then fall from the cloud layer, creating “fall streak holes“). The ice crystal clouds appear as darker shades of cyan on the false-color image.

GOES-16 "Red" Visible (0.64 µm) and Near-Infrared "Snow/Ice" (1.61 µm) images over Illinois/Indiana [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images over Illinois/Indiana [click to play MP4 animation]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images showed the hole punch and distrail features over Illinois/Indiana (above) and over Indiana/Ohio (below). The glaciated (ice crystal) hole punch and distrail clouds appeared dark gray on the Snow/Ice images (since ice is a strong absorber of radiation at the 1.61 µm wavelength).

GOES-16 "Red" Visible (0.64 µm) and Near-Infrared "Snow/Ice" (1.61 µm) images over Indiana/Ohio [click to play MP4 animation]

GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images over Indiana/Ohio [click to play MP4 animation]

RealEarth is used to display Suomi NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.9 µm), Near-Infrared (1.61 µm), True-color and False-color RGB images at 1841 UTC (below). O ne the Shortwave Infrared images, the hole punch and distrail features are colder (brighter white) than the surrounding supercooled water droplet cloud deck — since water droplet are effective absorbers of incoming solar radiation, such clouds appear warmer (darker gray) in 3.9 µm images.

Suomi NPP VIIRS

Suomi NPP VIIRS “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), Near-Infrared “Snow/Ice” (1.61 µm), True-color and False-color RGB images [click to enlarge]