Severe weather in the Mid-South, and heavy snow in the Upper Midwest

February 24th, 2018 |

GOES-16 Mid-level Water Vapor (6.9 µm), with hourly plots of surface weather type [click to play Animated GIF | MP4 also available]

GOES-16 Mid-level Water Vapor (6.9 µm) images, with hourly plots of surface weather type [click to play Animated GIF | MP4 also available]

GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) showed the flow of moisture from the lower Mississippi Valley into the Ohio Valley on 24 February 2018 — this fueled the development of flooding rainfall and severe thunderstorms (for more details, see the Satellite Liaison Blog). A special 21 UTC sounding from Little Rock AR indicated 37.3 mm or 1.47 inches of Total Precipitable Water (TPW) within the atmospheric column.

1-minute interval Mesoscale Sector GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (below) revealed the development of a small supercell thunderstorm just north of the Kentucky/Tennessee border — this storm produced an EF-2  tornado that was responsible for 1 fatality (NWS Louisville damage survey). This (along with another in Arkansas) was the first US tornado-related death in 283 days (a new record in terms of length), with the last occurring in Wisconsin on 16 May 2017.

GOES-16 "Red" Visible<em> (0.64 µm, left)</em> and "Clean" Infrared Window <em>(10.3 µm, right)</em> images, with hourly surface reports plotted in yellow and SPC storm reports plotted in red [click to play Animated GIF | <a href="http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2018/02/180224_goes16_visible_infrared_spc_storm_reports_KY_TN_severe_anim.mp4"><strong>MP4</strong></a> also available]

GOES-16 “Red” Visible (0.64 µm, left) and “Clean” Infrared Window (10.3 µm, right) images, with hourly surface reports plotted in yellow and SPC storm reports plotted in red [click to play Animated GIF | MP4 also available]

Farther to the north, bands of elevated convection (oriented generally west to east) developed across Minnesota and Wisconsin, as seen in GOES-16 Visible (0.64 µm) and Infrared Window (10.3 µm) images (below). Snowfall rates were 1-2 inches per hour at some locations, with many storm total accumulations of 7 to 9 inches. Note the small-scale “ripple structure” that was present along the tops of many of these convective bands (orthogonal to the long axis of each band).

GOES-16

GOES-16 “Red” Visible (0/64 µm) images [click to play animation]

GOES-16

GOES-16 “Clean ” Infrared Widow (10.3 µm) images [click to play animation]

Comparisons of Terra and Aqua MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images (below) also showed these bands of elevated convection that helped to enhance snowfall rates. The layer of instability aloft was evident on the 00 UTC sounding from Chanhassen MN.

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Terra MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Aqua MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Aqua MODIS Visible (0.65 µm) and Infrared Window (11.0 µm) images [click to enlarge]

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]

Mid-latitude cyclone in the central US

January 22nd, 2018 |

GOES-16 Water Vapor (6.9 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

5-minute GOES-16 Water Vapor (6.9 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

A large mid-latitude cyclone intensified over the central US on 22 January 2018, producing a wide variety of weather — in the cold sector, heavy snow and blizzard conditions across the Plains and Upper Midwest (WPC storm summary), and in the warm sector, severe weather (tornadoes, large hail and damaging winds: SPC storm reports) from Mississippi to Illinois, Indiana, and Ohio. GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) showed the large size of the storm circulation, which included a well-defined Warm Conveyor Belt (WCB) and a Trough of Warm Air Aloft (TROWAL) as identified here. More information on conveyor belts and TROWALs is available here.

A GOES-16 Mesoscale Sector provided 1-minute imagery over the Upper Midwest — “Red” Visible (0.64 µm) images (below) revealed some of the convective elements surrounding the surface low as it reached its occluded stage over Iowa. A small cluster of thunderstorms also developed over central Illinois around 19 UTC, producing 1.0-inch diameter hail.

GOES-16 Visible (0.64 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

1-minute GOES-16 Visible (0.64 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

Taking a  closer look at the eastern portion of the previous satellite scene, there was an overlap between the M1 and M2 Mesoscale Sectors — this allowed for images at 30-second intervals (below).

30-second GOES-16 Visible (0.64 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

30-second GOES-16 Visible (0.64 µm) images, with hourly precipitation type plotted in yellow [click to play MP4 animation]

Ice dam in Lake Erie

January 19th, 2018 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in yellow and wind gusts (knots) plotted in cyan [click to play animation]

Thanks to Dave Zaff (NWS Buffalo) for the email alerting us to an ice dam that had formed across the eastern portion of Lake Erie on 19 January 2018 — GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed that the northeastward drift of ice floes was effectively being blocked by this ice dam feature.

A toggle between 250-meter resolution Terra MODIS True-color and False-color Red-Green-Blue (RGB) images from the MODIS Today site (below) provided a more detailed view of the Lake Erie ice dam and upwind drift ice at 1615 UTC. Snow and ice appear as shades of cyan in the False-color image, in contrast to supercooled water droplet clouds which are shades of white.

Terra MODIS True-color and False-color RGB images [click to enlarge]

Terra MODIS True-color and False-color RGB images; red arrows denote the location of the ice dam [click to enlarge]

The Terra MODIS Visible (0.65 µm) image with an overlay of RTMA surface winds (below) showed the southwesterly flow across the long axis of the lake.

Terra MODIS Visible (0.65 µm) image with surface METAR reports and RTMA surface winds [click to enlarge]

Terra MODIS Visible (0.65 µm) image with surface METAR reports and RTMA surface winds [click to enlarge]

A toggle between 1607 UTC Terra MODIS and 1757 UTC Suomi NPP VIIRS Visible images (below) showed the motion of the lake drift ice during that time period.

Terra MODIS and Suomi NPP VIIRS Visible images, with METAR surface reports [click to enlarge]

Terra MODIS and Suomi NPP VIIRS Visible images, with METAR surface reports [click to enlarge]