23 March 2017 Convection and Dust in Texas / New Mexico

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.

On the afternoon of 23 March 2017, an upper level trough in the western US moving eastward was responsible for a strong lee cyclogenesis event.  The mesoscale sector for GOES-16 observed convection along the dryline with blowing dust on either side of it:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/23mar17/vis_meso&loop_speed_ms=80

The dust is lighter in color.  To the east of the dryline, it’s oriented in boundary layer rolls oriented NNW-SSE while west of the dryline where the boundary layer is much deeper in a hot / dry air mass, the dust is much more widespread.  What additional details can you see in the convection that you normally would not see with GOES-13/15?

In a GOES-16 4 panel loop showing all 3 water vapor bands in addition to the RGB Air Mass Product:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/23mar17/wv_amrgb&loop_speed_ms=80

What additional features do you see?  Do you see the blowing dust in any of the water vapor bands?  Why would the dust be observed in these band(s)?  Hint, see the weighting function profile for the 3 GOES-16 water vapor bands, based on the sounding from Amarillo, TX at 0000 UTC 24 March:

ama_wf

 

Remember that the weighting function profile is valid for clear skies only

Posted in Convection, Dust, GOES R, Severe Weather | Leave a comment

24 March 2017 fog / low stratus in the West

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.

On the morning of 24 March 2017, there were some interesting fog / low stratus events in the West.  In northeast Montana, we can see fog surging up the Milk River Valley in the GOES-16 visible imagery:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/24mar17/MT&loop_speed_ms=80

Saturated soil (due to snowmelt runoff flooding) from the Big Muddy Creek contributed to the fog event:

Meanwhile, at the same time in Arizona we see fog / low stratus sloshing back and forth (most likely in a canyon or valley) south of Sedona:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/24mar17/AZ&loop_speed_ms=80

 

Posted in Ceilings, Fog, GOES R, Orographic Effects, Visibility | Leave a comment

22 March 2017 undular bore

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.

An undular bore occurred on the morning of 22 March in the southern states and can be seen in this GOES-16 visible loop from southern Mississippi, northwestward across Louisiana into northeast Texas:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/22mar17/B02

Compare and contrast with the 1.6 micron loop over the same time period:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/22mar17/B05

 

Posted in GOES R, Satellites | Leave a comment

14 March 2017 Blizzard

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.

The 13-14 March 2017 blizzard that affected portions of the northeast can be viewed from a moisture perspective via the CIRA advected layer precipitable water (LPW) product:

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/14mar17/alpw

The loop shows the rapid advection of moisture northward from the Gulf of Mexico and off the southeast US coast.  Once the low started to deepen rapidly, moisture convergence also contributed to increasing moisture through a deep layer.

An overlay of winds (ASCAT surface winds over the sfc – 850 mb layer, and RAP model winds for their respective layers in the other panels):

alpw_winds_z3

gives an idea of the wind at different levels to readily identify moisture source regions.

A closer look at the ASCAT wind pass overlaid with the RGB airmass product and surface observations clearly shows the circulation around the surface low:

rgbam_ascat_16z_zout

Finally, GOES-16 1-minute visible imagery over the Washington DC vicinity provides a spectacular view of gravity waves that exist at many spatial/temporal scales:

http://rammb.cira.colostate.edu/ramsdis/online/loop.asp?data_folder=loop_of_the_day/goes-16/20170314000000&number_of_images_to_display=100&loop_speed_ms=40

 

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