Ice in the western Great Lakes

February 4th, 2018 |

GOES-16 "Red" Visible (0.64 µm) images, with plots of hourly surface reports [click to play animation]

GOES-16 “Red” Visible (0.64 µm) images, with plots of hourly surface reports [click to play animation]

After several days of cold temperatures, ice coverage in the western half of Lake Superior began to increase — and GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the motion of some of this lake ice (which was driven by a combination of surface winds and lake circulations) on 04 February 2018. That morning a number of locations in northern and northeastern Minnesota reported low temperatures in the -20 to -40 ºF range, with -43 ºF at Embarrass (the coldest location in the Lower 48 states).

With an overpass of the Landsat-8 satellite at 1646 UTC, a 30-meter resolution False-color Red-Green-Blue (RGB) image (below) provided a very detailed view of a portion of the Lake Superior ice. NOAA-GLERL analyzed the mean ice concentration of Lake Superior to be at 23.9% ; the Canadian Ice Service analyzed much of the new lake ice to have a concentration of 9/10ths to 10/10ths.

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Magnified sections of the Landsat-8 RGB image swath are shown below, moving from northeast to southwest.

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Moving to the south, a closer look at Green Bay in northeastern Wisconsin revealed a few small ice floes drifting from the north end of the bay into Lake Michigan (below).

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with plots of hourly surface reports [click to play animation]

Eruption of Volcán de Fuego in Guatemala

February 1st, 2018 |

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Snow/Ice” (1.61 µm, top), Near-Infrared “Cloud Particle Size” (2.24 µm, middle) and Shortwave Infrared (3.9 µm, bottom) images [click to animate]

After a series of occasional weak emissions during the previous month, a small eruption of Volcán de Fuego began during the pre-dawn hours on 01 February 2018. The thermal anomaly or “hot spot” could be seen on GOES-16 (GOES-East) Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 µm) images (above). In terms of the two Near-Infrared bands, even though the 1.61 µm band has better spatial resolution (1 km at satellite sub-point), the 2-km resolution 2.24 µm band is spectrally located closer to the peak emitted radiance of very hot features such as active volcanoes or large fires.

Multi-spectral retrievals of Ash Cloud Height from the NOAA/CIMSS Volcanic Cloud Monitoring site (below) indicated that volcanic ash extended to altitudes in the 4-6 km range (yellow to green enhancement), with isolated 7 km pixels at 1315 UTC. The product also showed the effect of a burst of southwesterly winds just after 11 UTC, which began to transport some of the ash northeastward (as mentioned in the 1332 UTC advisory).

GOES-16 Ash Height product [click to animate]

GOES-16 Ash Height product [click to animate]

At 1624 UTC, a 30-meter resolution Landsat-8 False-color Red-Green-Blue (RGB) image viewed using RealEarth (below) showed the primary ash plume drifting to the west, with some lower-altitude ash spreading out northward and southward. A thermal anomaly was also evident at the summit of the volcano.

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

Flooding in Southern California

January 9th, 2018 |

1-minute GOES-16 Infrared Window (10.3 µm) images; with hourly reports of surface weather type plotted in yellow [click to play MP4 animation]

1-minute GOES-16 Infrared Window (10.3 µm) images; with hourly reports of surface weather type plotted in red [click to play MP4 animation]

An onshore flow of moisture (MIMIC TPW) in tandem with forcing for ascent with the approach of an upper-level low and a surface cold/occluded front brought heavy rainfall and some higher-elevation snowfall (NWS LOX/SGX | WPC) to much of Southern California on 09 January 2018. To help monitor the event, a GOES-16 (GOES-East) Mesoscale Sector was positioned over the region, providing images at 1-minute intervals. “Clean” Infrared Window (10.3 µm) images (above) showed the colder clouds associated with periods of moderate to heavy rainfall. Some of this precipitation fell over burn scar areas from wildfires that occurred in December 2017 — including the Thomas fire, which was the largest on record for the state of California — resulting in numerous mud/debris slides that caused at least 17 fatalities, destroyed/damaged hundreds of homes, and closed many streets and highways.

GOES-16 “Red” Visible (0.64 µm) images (below) showed some of the features which helped produce heavier rainfall and snowfall during the daylight hours on 09 January.

1-minute GOES-16

1-minute GOES-16 “Red” Visible (0.64 µm) images; with hourly reports of surface weather type plotted in red [click to play MP4 animation]

The circulation of the upper-level low was easily seen on GOES-16 Mid-level Water Vapor (6.9 µm) images (below).

1-minute GOES-16 Water Vapor (6.9 µm) images; with hourly reports of surface weather type plotted in red [click to play MP4 animation]

1-minute GOES-16 Water Vapor (6.9 µm) images; with hourly reports of surface weather type plotted in red [click to play MP4 animation]

===== 10 January Update =====

Suomi NPP VIIRS True-color and False-color RGB images [click to enlarge]

Suomi NPP VIIRS True-color and False-color RGB images [click to enlarge]

On the following day, a toggle between Suomi NPP VIIRS True-color and False-color Red-Green-Blue (RGB) images from RealEarth (above) showed (1) the large burn scar from the Thomas Fire (shades of reddish-brown), and (2) snow cover in the higher terrain (darker shades of cyan) on the False-color image. The True-color image revealed sediment from runoff flowing into the nearshore waters from Santa Barbara to Oxnard (shades of brown to light green).

A closer look at the Thomas Fire burn scar was provided by 30-meter resolution Landsat-8 False-color RGB imagery (below), which showed thin filaments of muddy sediment just offshore, as well as fresh snow cover (shades of cyan) along or immediately adjacent to the northeastern edge of the burn scar (in the Hines Peak area). On 10 January, the fire was listed as 92% contained (100% containment was declared on 12 January).

Landsat-8 False-color RGB image [click to enlarge]

Landsat-8 False-color RGB image [click to enlarge]

===== 11 January Update =====

Suomi NPP VIIRS True-color images on 10 January and 11 January [click to enlarge]

Suomi NPP VIIRS True-color images on 10 January and 11 January [click to enlarge]

A comparison of Suomi NPP VIIRS True-color RGB images on 10 January and 11 January (above) showed that sediment was flowing farther offshore from the Thomas Fire burn scar area.

Farther to the south, offshore sediment transport was also seen in the San Diego area (below).

Suomi NPP VIIRS True-color image on 11 January [click to enlarge]

Suomi NPP VIIRS True-color image on 11 January [click to enlarge]

Ice floes in Chesapeake Bay

January 7th, 2018 |

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 false-color RGB image [click to enlarge]

In the wake of the explosive cyclogenesis off the East Coast of the US on 04 January 2018, very cold air began to spread across much of the eastern half of the Lower 48 states. Focusing on the Hampton Roads area of southeastern Virginia, satellite imagery began to show the formation of ice in the rivers and bays. On 06 January, a 30-meter resolution Landsat-8 false-color Red-Green-Blue (RGB) image viewed using RealEarth (above) revealed some of this ice — in particular, long narrow ice floes (snow and ice appear as shades of cyan) that likely emerged from the Back River (northeast of Hampton) and were drifting northward and southward just off the coast of the Virginia Peninsula.

On the following day (07 January), 250-meter resolution Terra MODIS true-color and false-color RGB images from the MODIS Today site (below) showed that a larger V-shaped ice floe was located just southeast of the Peninsula, with its vertex pointed toward the Hampton Roads Bridge-Tunnel (HRBT). Snow and ice also appear as shades of cyan in the MODIS false-color image.

Terra MODIS true-color and false-color RGB images [click to enlarge]

Terra MODIS true-color and false-color RGB images [click to enlarge]

07 January also happened to be the last full day of imagery to be broadcast by the GOES-13 satellite — a comparison of 1-minute Mesoscale Sector GOES-16 (GOES-East) Visible (0.64 µm) and 15-30 minute interval GOES-13 Visible (0.63 µm) images (below) showed that the V-shaped ice floe continued to drift southwestward toward the HRBT. However, it was difficult to tell whether the ice feature made it over and past the tunnel; even with the improved GOES-16 Visible spatial resolution (0.5 km at satellite sub-point, compared to 1.0 km for GOES-13) and the 1-minute rapid image scans, the ice floe became harder to track during the afternoon hours before high clouds began to overspread the region.

"GOES-16

GOES-16 Visible (0.64 µm, left) and GOES-13 Visible (0.63 µm, right) images, with hourly surface air temperatures (ºF) plotted in yellow [click to play MP4 animation]

However, a close examination of Suomi NPP VIIRS true-color and false-color images at 1826 UTC (below) indicated that some of the ice had indeed moved westward past Fort Monroe (on the far southeastern tip of the Peninsula) and over/past the HRBT.

Suomi NPP VIIRS true-color and false-color RGB images [click to enlarge]

Suomi NPP VIIRS true-color and false-color RGB images [click to enlarge]

On the topic of cold temperatures in southeastern Virginia, a new daily record low of -3 ºF was set at Richmond on the morning of 07 January, and at Norfolk new daily record low and record low maximum temperatures were set (10 ºF and 23 ºF, respectively).