Island / coastal effects in the northeast on 19 June 2017

The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing.  Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.

A loop of GOES-16 visible (0.64 micron) imagery on 19 June 2017 over the northeast:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/19jun17&loop_speed_ms=80

illustrates the effects of various islands and coastalines.  The surface winds are southerly with warm/moist air advecting northwards.  Low clouds (and perhaps fog) develop over the ocean as the warm/moist air advects over the relatively cooler ocean surface.  These low clouds converge along the coastlines as well as various islands.  The islands also act as a barrier to the flow with various convergence / divergence patterns around the islands.

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Colorado: Dead Dog Wildfire

Another fire is catching headlines in Colorado the past few days, it is called the Dead Dog Wildfire located within Dead Dog Gulch. The fire is located approximately 10 miles north-west of Rangely, Colorado. Hot, windy and dry conditions have persisted in northwest Colorado over the past few days, where the fire initiated over the past weekend. According to news outlets, the fire has burned approximately 18,000+ acres so far and will continue to burn more acreage.

To visualize and emphasize the magnitude of the wildfire, one can use the Day/Night Band (DNB) which utilizes a sun/moon reflectance model to illuminate atmospheric features, sense emitted lights and assist in cloud monitoring during the nighttime. A DNB satellite image is shown below, where the fire is located within the highlighted red circle. To complement the DNB, one can also use the I-4 band (3.74um), also provided below, which senses fire ‘hotspots': areas where the satellite sensor recognizes ‘hot’ regions, expressed in brightness temperatures (i.e. orange, yellow and red colors) on the Earth’s surface.

DNB image taken at 0849Z, 13 June 2017

DNB_one

I-4 Band (3.74um)  image taken at 0849Z, 13 June 2017

IR_one

The latest updates of the fire can be seen via the following link.

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Mesoscale Convective Vortex (MCV) over Texas on 9 June 2017

The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing.  Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.

GOES-16 IR band 13 at 10.35 microns depicts an MCS across Texas:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/8jun17/B13&loop_speed_ms=100

The MCS decays during the loop.  Can you identify a Mesoscale Convective Vortex (MCV) in this loop?

Next, look at the GOES-16 visible (0.64 micron) loop:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/8jun17/B02&loop_speed_ms=100 

Now can you identify a Mesoscale Convective Vortex (MCV)?  On the northwest flank of the decaying convection, a circulation can be readily seen in the visible imagery associated with a MCV.  Note that it can be detected in the IR loop as well, although it was more subtle.  In fact, due west of the decaying convection we can see another circulation, likely an MCV associated with convection that took place prior to the start of the IR loop.

For MCV identification, using both IR and visible imagery in tandem is ideal in that the IR imagery can trace the origins of the MCV from the MCS while the visible imagery generally provides a clear indication of the circulation associated with the MCV after the decay of the MCS.

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Tropical Storm Beatriz

Yesterday evening, Thursday, 1 June 2017, Tropical Storm Beatriz made landfall in southern Mexico state of Oaxaca. The tropical storm brought heavy rains, flooding and mudslides to the area, resulting in 2 deaths as of Friday, 2 June 2017. Once deemed a tropical storm, turned back into a tropical depression soon after making landfall and is currently a remnant low. Flights were cancelled across the region where the city of Puerto Angel received 9+ inches of rain so far. The storm is moving slowly over southern Mexico, and high amounts of precipitation is expected across the region over the next few days.

Looking at the latest overpass from the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite, Beatriz is highlighted by one of the 22 spectral channels (i.e. Imagery Band 5 (I-5) (11.45um)) apart of the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument on-board Suomi-NPP. The I-5 band is an infrared band that detects the emissivities of the atmospheric phenomena and land/ocean surfaces (i.e. the amount of thermal energy produced by atmospheric phenomena and surface features, detected by satellite).

The image below describes the thermal energy detected by satellite via brightness temperatures in degrees Kelvin over the southern Mexico and Central America domain. The range of brightness temperatures are from 180K (-132 degrees F) to 320K (116 degrees F). The low to high clouds are seen via cooler colors (i.e. blue, light blue), while the land and ocean are seen via warmer colors (i.e. orange). One can see the location of tropical storm Beatriz as it made landfall in southern Mexico at 0711Z, 2 June 2017. There are also small storms located east of Beatriz along the Yucatan Peninsula.

modified_I5_06022017

*Sources: National Hurricane Center and The Weather Channel.

Posted in Heavy Rain and Flooding Issues, Miscellaneous, POES, Satellites, Tropical Cyclones | Leave a comment