The toggle above includes nocturnal visible Suomi NPP VIIRS  Day Night Band (0.7 µm) imagery over New England after a strong storm (blogged here), compared with a reference image from 04 October 2017.  The primary nighttime light source for the Day Night Band over land on 31 October was cities (since the Moon was below the horizon), thus a comparison between the latest image with one earlier in the month having different lunar illumination (from October 4th) highlights regions that experienced significant power outages due to high winds.  Clouds will affect the interpretation of the Day Night Band imagery, and a reference Infrared Window (11.45 µm) image from 31 October at 2:38 AM EST is here.  The Day Night Band image with only cloud outlines is here.  (VIIRS imagery courtesy of Will Straka, CIMSS).

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

GOES-16 Mid-level Water Vapor (6.9 µm) images with hourly surface weather symbols plotted in red (above) showed the large-scale evolution of a storm system that deepened rapidly as it moved across the Northeast US during the 29 October – 30 October 2017 period (surface analyses). This storm produced widespread high winds and heavy rain (WPC storm summary | NWS Boston PNS | NWS Caribou PNS). Record low sea level pressures for the month of October were set in New York at Albany (977.7 hPa) and Fort Drum (977.5 hPa), and in Massachusetts at Nantucket (982.6 hPa) — a map of the minimum sea level pressures from the New York State Mesonet can be seen here.

Closer views of the Northeast US using images from the GOES-16 Upper-level Water Vapor (6.2 µm), Mid-level Water Vapor (6.9 µm) and Low-level Water Vapor (7.3 µm) bands are shown below, with hourly surface wind gusts (knots) plotted in red. The high winds caused extensive damage to trees and power lines, leading to power outages in some areas — and also contributed to coastal storm surge.

One interesting aspect of this rapidly-deepening storm was the absorption/merging of the northward-moving remnants of Tropical Storm Philippe (storm track), which was shown by the CIMSS 850 hPa relative vorticity product (below).

Additional details of this event can be found on the Satellite Liaison Blog.

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

The ABI “Cirrus” (1.37 µm) band is centered in a strong water vapor absorption spectral region — therefore it does not routinely sense the lower troposphere, where there is usually substantial amounts of water vapor. Hence, its main application is the detection of higher-altitude cirrus cloud features.

However, in areas of the atmosphere characterized by low amounts of total precipitable water, the Cirrus band can sense clouds (and other features, such as blowing dust) in the lower troposphere. Such was the case on 29 October 2017, when a ribbon of dry air resided over the northern Gulf of Mexico in the wake of a strong cold frontal passage; low-level stratocumulus clouds were very apparent on GOES-16 Cirrus band images (above). Also of note: cloud features associated with Tropical Storm Philippe could be seen east of Florida.

The three GOES-16 Water Vapor bands (Upper-level 6.2 µm, Mid-level 6.9 µm and Lower-level 7.3 µm) highlighted the pocket of dry air that was moving across the northern Gulf of Mexico on that day (below).

The MODIS instrument on Terra and Aqua has a 1.37 µm Cirrus band as well; 1619 UTC Terra images (below) also revealed the stratocumulus clouds (especially those over the northeastern Gulf, where the driest air resided). Conversely, note how the low cloud features of Philippe were not seen on the Cirrus image, since abundant moisture within the tropical air mass east of Florida attenuated 1.37 µm wavelength radiation originating from the lower atmosphere.

In addition, the VIIRS instrument — on Suomi NPP, and the upcoming JPSS series — has a 1.37 µm Cirrus band.

Hourly images of the MIMIC Total Precipitable Water product (below) showed the ribbon of very dry air (TPW values less than 10 mm or 0.4 inch) sinking southward over the northern Gulf of Mexico. This TPW product uses microwave data from POES, Metop and Suomi NPP satellites (description).

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

With high pressure dominating across the region during the pre-dawn nighttime hours (surface analyses), strong radiational cooling (minimum temperatures) aided in the formation of widespread valley fog across New England on 28 October 2017.  Post-sunrise GOES-16 “Red” Visible (0.64 µm) images revealed the areal extent of the valley fog; however, fog dissipation was fairly rapid during the morning hours as surface heating from abundant sunlight promoted sufficient boundary layer mixing.

During the preceding nighttime hours, development of widespread valley fog could be seen on Suomi NPP VIIRS Infrared Brightness Temperature Difference (11.45 µm – 3.74 µm) images (below) — although surface fog features were obscured at times by patchy cirrus clouds aloft (black enhancement). This example demonstrates that because of the wide (3000 km) scan swath of the VIIRS instrument, in many cases the same region might be sampled by 2 consecutive overpasses. VIIRS will also be part of the instrument payload on the upcoming JPSS series of polar-orbiting satellites.

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