** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

As pointed out by NWS Caribou:

Beautiful gravity waves over Gulf of Maine today, at several different levels too! #GOES16 data is preliminary, non-operational. #mewx pic.twitter.com/jbQEbAnPzz

— NWS Caribou (@NWSCaribou) April 27, 2017

numerous packets of wave clouds associated with undular bores were seen on GOES-16 Visible (0.64 µm) imagery over the Gulf of Maine on the morning of 27 April 2017. A longer animation with surface wind plots (below; also available as an MP4 animation) revealed the presence of 3 distinct bore structures: the largest and most well-defined which was moving eastward; a second (and much smaller) off the coast of Cape Cod which was moving southeastward; and a third which as moving northwestward  (and eventually intersected the northern end of the primary eastward-moving bore).

A comparison of GOES-16 and GOES-13 (GOES-East) Visible images (below; also available as an MP4 animation) showed that undular bore wave cloud structures were more clearly clearly seen with the higher spatial spatial resolution of GOES-16 (0.5 km at satellite sub-point, vs 1.0 km for GOES-13). The comparison also showed that the visible imagery from GOES-13 (launched in May 2006, and operational as GOES-East since April 2010) was not as bright as that from GOES-16; this is due to the fact that the performance of GOES visible detectors tends to degrade over time.

So what caused these undular bores to form and propagate across the Gulf of Maine? Such gravity waves are ducted within strong temperature inversions — and rawinsonde data from Chatham, Massachusetts and Yarmouth, Nova Scotia indicated that such inversions were in place above the surface that morning. The northwestward-moving bore could have been initiated by surface outflow from thunderstorms associated with a mid-latitude cyclone (which was producing storm force and gale force winds: surface analyses) — GOES-16 Infrared Window (10.3 µm) images (below; also available as an 88 Mbyte animated GIF) showed these thunderstorms which developed within the warm sector of the coastal low pressure system. However, the forcing mechanism(s) that generated the eastward and southeastward moving bores remains somewhat of a mystery.

View only this post Read Less

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

A daytime comparison of GOES-16 ABI “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above; also available as an MP4 animation) displayed the smoke plume and “hot spots” (black to yellow to red pixels) associated with the West Mims Fire that was burning in far southeastern Georgia on 25 April 2017 (this fire complex had been burning since 06 April, during which time the drought conditions had been worsening across that region). Downwind of the fire, in far northeastern Florida, smoke reduced the surface visibility to 2 miles at Jacksonville and 5 miles at Fernandina Beach.

During the subsequent nighttime hours — as the fires were beginning to decrease in both intensity and areal coverage — a comparison of “Snow/Ice” Near-Infrared (1.61 µm), “Cloud-Top Phase” Near-Infrared (2.24 µm) and Shortwave Infrared (3.9 µm) images (below; also available as an MP4 animation) showed that a bright glow from the most intense fires was evident in both of the Near-Infrared spectral bands.

Although the spatial resolution of the 1.61 µm Band 5 is 1 km (at satellite sub-point) versus 2 km for the 2.24 µm Band 6, the bright nighttime fire signature was more defined on the 2.24 µm imagery; this is explained by examining a plot of the Spectral Response Function (SRF) for each band (below; courtesy of Mat Gunshor, CIMSS). For a very hot fire target — represented by the red 1200 K line — the 2.24 µm Band 6 SRF is located near the peak of the 1200 K curve, so more of the fire-emitted radiance can be sensed by Band 6 (in spite of its lower spatial resolution).

View only this post Read Less

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

To commemorate Earth Day 2017, Full Disk images using all 16 spectral bands on the GOES-16 ABI instrument at 17:25:22 UTC on 22 April are displayed above. One feature that was prominent in most of the shorter-wavelength bands — which are able to sense a good deal of radiation/reflectance from the Earth’s surface — was the large area of sun glint near the center of the images (over the Pacific Ocean, just west of Panama/Costa Rica). The westward migration of this sun glint signature could be followed on an animation of Visible (0.64 µm) images (below). GOES-16 remained in a Mode 4 scan strategy during much of the day (until 1930 UTC), providing Full Disk images every 5 minutes.

Taking a closer look at a portion of the Amazon River in Brazil, a comparison of Blue Visible (0.47 µm), Red Visible (0.64 µm) and Near-Infrared Vegetation (0.86 µm) band imagery (below) highlighted the ability of the 0.86 µm images to discriminate between land and water (water appears very dark). This makes 0.86 µm imagery useful for identifying and monitoring areas of inland flooding.

View only this post Read Less

** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **

GOES-16 was operated in “Mode 4” on 21 April 2017 — this scanning strategy provides Full Disk images every 5 minutes (the current routine scan schedule for GOES-15 and GOES-13 only provides one Full Disk image every 3 hours). Shown below are animations of Upper-Level Water Vapor (6.2 µm), Mid-Level Water Vapor (6.9 µm) and Lower-Level Water Vapor (7.3 µm) Full Disk images covering the 12:00 to 23:55 UTC period. You can explore the differences between Water Vapor weighting functions for these 3 ABI bands (and how they change depending on airmass type, satellite viewing angle, etc) at this site.

View only this post Read Less