Convection and Flooding over northern Wisconsin

June 17th, 2018 |

GOES-16 ABI Clean Window (10.3 µm) Infrared Imagery, 0200-0559 UTC on 17 June 2018 (Click to animate)

Persistent convection over northern Wisconsin, Minnesota and upper Michigan late Saturday (16 June)/early Sunday (17 June) caused significant flooding.  The animation above shows GOES-16 ABI “Clean Window” Infrared Imagery from 0200-0600 UTC on 17 June.  Note the persistence of the cold overshooting tops over western Bayfield County in northwestern Wisconsin! A longer Infrared animation (0110-1200 UTC) which includes hourly plots of precipitation type (yellow) and SPC storm reports of damaging winds (cyan) is available here. 7-day precipitation departures in some areas were 4 to 8 inches above normal for that period (or 600% of normal).

This link from Wisconsin Emergency Management shows aerial pictures of the flood damage. Of note is the break in US Highway 2 to the west of Ashland WI.

The heavy rains also affected runoff into Lake Superior. MODIS imagery, below, from the MODIS Today site (also available from RealEarth: Link), shows considerable offshore flow of sediment on 19 June (a similar image from 18 June is here, with a toggle between the 2 days here).

True-Color Imagery from Aqua MODIS on 19 June 2018 (Click to enlarge)

A Landsat-8 False-Color image, below, showed pockets of flooding (darker blue) adjacent to the Nemadji River in Superior WI on the morning of 19 June — water also cover a portion of US Highway 2/53. The Nemadji River had crested in Superior at a record 29.5 feet on the evening of 17 June (NWS Duluth summary).

Landsat-8 False-Color image (Click to enlarge)

False-Color image from Landsat-8 on 19 June 2018 (Click to enlarge)


============================ Added 22 June ==============================
 

NOAA’s Hydrometeorological Design Studies Center (Link) created an Exceedance Probability Analysis for this event at 6-hour, 24-hour and 72-hout time spans, available here (from this link). Probabilities suggest this was an exceedingly rare event.

The continuation of sediment flow into Lake Superior could be seen in a series of daily MODIS True-Color images here.

Cape Newenham, Alaska bow shock waves

June 10th, 2018 |

GOES-15 Visible (0.63 µm) images, with hourly plots of wind barbs [click to play animation]

GOES-15 Visible (0.63 µm) images, with hourly plots of wind barbs [click to play animation]

GOES-15 (GOES-West) Visible (0.63 µm) images (above) showed patches of fog and low stratus moving southwestward off Southwest Alaska and across the adjacent offshore waters of the Bering Sea on 10 June 2018.

A closer look using 250-meter resolution Terra/Aqua MODIS and 375-meter resolution Suomi NPP VIIRS true-color Red-Green-Blue (RGB) images from RealEarth (below) revealed a packet of “bow shock waves” created as the shallow fog/stratus interacted with the relatively rugged terrain of the narrow Cape Newenham land feature (Google Maps). Other examples of similar bow shock wave cloud features have been documented here, here and here.

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color RGB images [click to enlarge]

Terra MODIS, Aqua MODIS and Suomi NPP VIIRS true-color RGB images [click to enlarge]

A 30-meter resolution Landsat-8 false-color RGB image (below) provided a more detailed view of the bow shock wave structure. Snow cover (cyan) could be seen on some of the higher-elevation land features.

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

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

A time series plot of Cape Newenham surface observations (below) showed the fluctuations in visibility as northerly winds brought patches of fog over the site.

Time series plot of Cape Newenham surface observations [click to enlarge]

Time series plot of Cape Newenham surface observations [click to enlarge]

Large grass fires continue to burn in the southern Plains

April 17th, 2018 |

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly plots of surface reports [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly plots of surface reports [click to play MP4 animation]

1-minute Mesoscale Sector GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) images (above) showed a number of “hot spot” signatures (dark black to red pixels) associated with grass fires that began burning in southeastern Colorado, southwest Kansas and the Oklahoma/Texas Panhandles on 17 April 2018. These fires spread very rapidly with strong surface winds (as high as 81 mph at Wolf Creek Pass CO) and very dry fuels due to Extreme to Exceptional drought. In addition to these new fires, hot pixels from the ongoing Rhea Fire in northwest Oklahoma (which began burning on 12 April) were still apparent.

During the subsequent nighttime hours, a strong cold front plunged southeastward across the region (surface analyses) — and on a closer view of GOES-16 Shortwave Infrared images (below), 2 different behaviors were seen for 2 of the larger fires. As the cold front moved over the Badger Hole Fire that was burning along the Colorado/Kansas border, an immediate decreasing trend in hot spot intensity and coverage was noted. Farther to the southeast, when the cold front later moved over the Rhea Fire in northwest Oklahoma a flare-up in hot spot intensity and coverage was evident.

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly plots of surface reports [click to play MP4 animation]

GOES-16 Shortwave Infrared (3.9 µm) images, with hourly plots of surface reports [click to play MP4 animation]

===== 18 April Update =====

A nighttime comparison of (Preliminary, Non-Operational) NOAA-20 VIIRS Day/Night Band (0.7 µm), I-Band Shortwave Infrared (3.75 µm), M-Band Shortwave Infrared (4.05 µm), and M-Band Near-Infrared (1.61 µm and 2.25 µm) images (below; courtesy of William Straka, CIMSS) showed a variety of fire detection signatures associated with the Rhea Fire (283,095 acres, 3% contained) in northwest Oklahoma.

NOAA-20 Day/Night Band (0.7 µm), I-Band Shortwave Infrared (3.75 µm), M-Band Shortwave Infrared (4.05 µm), M-Band Near-Infrared (1.61 µm and 2.25 µm) images [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm), I-Band Shortwave Infrared (3.75 µm), M-Band Shortwave Infrared (4.05 µm), M-Band Near-Infrared (1.61 µm and 2.25 µm) images [click to enlarge]

The early afternoon 1-km resolution Aqua MODIS Land Surface Temperature product (below) indicated that LST values within the Rhea burn scar (which covered much of Dewey County in Oklahoma) were as high as 100 to 105 ºF (darker red enhancement) — about 10 to 15 ºF warmer than adjacent unburned vegetated surfaces.

Aqua MODIS Land Surface Temperature product [click to enlarge]

Aqua MODIS Land Surface Temperature product [click to enlarge]

===== 19 April Update =====

A 30-meter resolution Landsat-8 false-color image from RealEarth (below) provided a detailed view of the Badger Hole Fire, which had burned 48,400 acres along the Colorado/Kansas border.

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

Landsat-8 false-color image [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]