Hurricane Aletta
June 8th, 2018 by Jorel TorresHurricane Aletta has grown tremendously over the past 24 hours, and it is now determined as a Category 4 hurricane, as of this morning, 8 June 2018. Aletta is currently located southwest of Mexico, in the eastern Pacific Ocean. Aletta is moving northwestward, and is forecasted to drop in intensity by the weekend, as the system moves into higher wind shear, colder sea surface temperatures and decreasing ocean heat content. Aletta is quite large in areal extent, where preliminary reports had the ‘eye’ of the storm at approximately 20-miles in diameter. The latest National Hurricane Center (NHC) forecast track of Aletta is seen below, valid at 3pm MDT, 8 June 2018.
Satellite imagery observing Hurricane Aletta is also provided. Below is the Advected Layered Precipitable Water (ALPW) product at 18Z, 8 June 2018, highlighting the areal extent and the moisture profile of the hurricane. Product is derived from a Microwave Integrated Retrieval System (MIRS), derived from polar-orbiting satellites, and is at a 16-kilometer resolution.
The ALPW product identifies, where the moisture is predominately concentrated within four layers (i.e. thicknesses) of the atmosphere: surface-850mb, 850-700mb, 700-500mb, and 500-300mb. In the image below, the color bar is uniform across all layers, where 0-3 inch precipitable water values are seen. For this event, the majority of the precipitable water is found near the surface, where precipitable water values are ~1 inch (orange, red colors), and values decrease aloft. Black colors within Hurricane Aletta, indicate ‘missing data’, where microwave retrievals can be made within cloudy regions, however, not through areas of precipitation.
Additionally, here is the latest RAMMB-SLIDER satellite imagery of Hurricane Aletta, using GOES-16, 0.64um, visible satellite imagery near 21Z, 8 June 2018. Click on the following animation.
For the latest updates on Hurricane Aletta, click the following link.
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Storm-relative animations for right-moving and left-moving storms
June 8th, 2018 by Dan BikosThis blog entry will compare traditional satellite animations of right-moving and left-moving storms with storm-relative animations as observed by GOES-16 visible imagery in AWIPS with the Feature Following Zoom tool. Also, comparisons will be made between different temporal resolutions, that is, AWIPS CONUS 5-minute versus mesoscale 1-minute sectors.
We will start with the traditional satellite animation which is for the 0.64 micron visible band CONUS sector (5-minute):
In the eastern Texas panhandle, we observe a storm that turns right (towards the southeast) as it intensifies. Meanwhile, in the northeast Texas panhandle into the Oklahoma panhandle we see a left-moving storm moving northeastward that appears to be moving faster than the right-moving storm.
Compare the animation with a storm-relative animation centered on the right-moving storm (CONUS sector):
and also compare with a storm-relative animation centered on the left-moving storm (CONUS sector):
How does the storm-relative animation affect your interpretation of the satellite imagery? What can you see more effectively in the storm-relative animations?
Fortunately, on this day a Mesoscale sector covered the region of interest, allowing us to make further comparisons with 1-minute temporal resolution imagery.
First, the traditional satellite animation for the Mesoscale sector:
Compare the animation with a storm-relative animation centered on the right-moving storm (Mesoscale sector):
and also compare with a storm-relative animation centered on the left-moving storm (Mesoscale sector):
How does the storm-relative animation affect your interpretation of the satellite imagery? What can you see more effectively in the storm-relative animations?
Summary:
The storm-relative animations definitely allow the user to more effectively analyze features at cloud top (overshooting tops, cloud motions, gravity waves). Features in the vicinity of the storm may be viewed more efficiently as well (clouds moving into the storm, such as potential inflow feeder clouds). Also, the storm motion relative to a boundary can be visualized more readily. This can be particularly useful in situations where you are monitoring storms that may go more parallel or perpendicular to a boundary with obvious consequences on storm intensity.
Storm speed can be seen in a relative sense as well, in this case we adjusted the loop speeds to make them look more favorable, but you may change the loop speed so that they are all the same to prove to yourself how much faster the left-moving storm is moving relative the right-moving storm. At the end of the URL, the loop_speed_ms= parameter can be edited to your preference, see what effects the same number (i.e., loop_speed_ms=20) has.
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Volcan de Fuego, Guatemala erupts again!
June 4th, 2018 by Jorel TorresYesterday, Volcan de Fuego erupted again in southern Guatemala. The pyroclastic flow of Fuego surprised many, and as of this morning 4 June 2018, at least 25 people have died, while many others are injured. Locals near Fuego, are in the process of being evacuated from the area.
Fuego erupted around 18 UTC, 3 June 2018, ejecting hot gas, smoke and ash in the atmosphere, where geostationary and polar-orbiting satellites observed the phenomena. Below is a video of the volcanic eruption, utilizing the CIRA-GeoColor satellite imagery from RAMMB-SLIDER, between 18-21 UTC, June 3 2018. Notice the rapid volcanic plume (brownish cloud) that develops and is advected eastward, within the time-frame.
The Suomi-National Polar-orbiting Partnership (SNPP) satellite also observed the volcanic plume. The Visible Infrared Imaging Radiometer Suite (VIIRS) True Color and Imagery Band 5 (11.45um, brightness temperature) both show static images of the events at ~19 UTC, 3 June 2018. Static images are taken approximately 1-hour after the volcanic eruption started. Both images are courtesy of the NASA Worldview data archive website.
VIIRS True Color Imagery
VIIRS Imagery Band 5 (11.45um, brightness temperatures)
For the latest updates on Fuego de Volcan, click the following link.
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Ute Park Fire, New Mexico
June 1st, 2018 by Jorel TorresThe Ute Park Fire initiated and has erupted over the past 24 hours. As of this morning, 1 June 2018, the fire has burned over 8,000 acres and is at zero percent containment, forcing mandatory evacuations. The fire is located in Ute Park, NM and is east of Eagle Nest, NM. Several structures have already been burned, and the cause of the fire is under investigation.
The Ute Park Fire and the Buzzard Fire (that has been burning for several weeks) can be seen in an array of satellite products and imagery, below.
The Near-Constant Contrast (NCC), a derived product of the Day/Night Band (DNB), utilizes a sun/moon reflectance model to illuminate atmospheric features during the nighttime, such as emitted (i.e. wildfires, city lights) and reflected (i.e. clouds) light sources. The emitted light from both fires can be seen in the NCC product below, along with the emitted city lights. Product is at 750-m resolution and image is taken at 0818 UTC, 1 June 2018.
In complement to the NCC, the GOES-16 3.9um, infrared satellite imagery is used to identify the ‘hotspots’ of the fires. In the imagery, brightness temperature values are high, expressing over 90 degree Celsius temperatures for the Ute Park Fire. The Buzzard Fire expressed lower brightness temperature values at this timestamp. Product is at 2-km resolution and image is taken at 0817 UTC, 1 June 2018.
Both fires are seen in the CIRA-GeoColor Product as well, highlighting the smoke from both fires. Video animation is taken between 15-16 UTC, 1 June 2018.
Now where is the smoke from the fires going to go? Utilizing an experimental High-Resolution Rapid Refresh (HRRR) Smoke Model, two forecast products can be used to potentially determine where the smoke is going to go. Both forecast products are the Near-Surface Smoke (expressed in micrograms per meter-cubed) and the Vertically Integrated Smoke (expressed in milligrams per meter-squared). Both products, seen below, are utilizing the 12 UTC run, valid at 00UTC 2 June 2018.
Near-Surface Smoke (below) determines the fire emitted Particulate Matter (PM2.5, also known as ‘fire smoke’) concentrations at approximately 8 meters above the ground.
Vertically Integrated Smoke (below) simulates the total PM2.5 mass within vertical columns over each model grid cell. Vertical columns are approximately 25-km above the ground. Product incorporates the smoke within the boundary layer and aloft, displaying the integral effect of ‘fire smoke’ throughout the atmosphere.
For more updates on the Ute Park Fire, click the following link.
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Alberto
May 29th, 2018 by Jorel TorresAs of 29 May 2018, subtropical depression Alberto has been advecting northward, through the southeastern United States. Alberto made landfall yesterday 28 May 2018, along the Gulf Coast, near the Florida Panhandle. Alberto produced heavy rainfall and has the potential for tornadoes, as it pushes north into the Ohio Valley within the next few days. Rain estimates are 3+ inches in several southeastern states.
Below are two static satellite images of Alberto. The first one is the Near-Constant Contrast (NCC), a derived product of the Day/Night Band (DNB). NCC utilizes a sun/moon reflectance model that illuminates atmospheric features, and senses emitted (i.e. city lights) and reflected light sources (i.e. clouds) during the nighttime. NCC imagery is taken at 0735Z, 29 May 2018, during the full-moon stage of the lunar cycle. Notice the large areal extent of Alberto, engulfing a few southeastern states. Spatial resolution is at 750-meters.
The second image is of the GOES-16 infrared, low-level water vapor imagery (channel 10, 7.3um) at 0737Z, 29 May 2018. Imagery shows the convective, cold cloud tops (cold brightness temperatures, indicated in blue and green colors) of Alberto that can produce heavy precipitation and severe weather. Spatial resolution is at 2-kilometers.
More updates on Alberto can be seen by the following link.
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