Flooding in South Dakota, Nebraska and Iowa

March 15th, 2019 |

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Vegetation” (0.86 µm) and “Snow/Ice” (1.61 µm) images [click to play animation | MP4]

GOES-16 (GOES-East) Near-Infrared “Vegetation” (0.86 µm) and “Snow/Ice” (1.61 µm) images (above) revealed widespread river flooding (in the wake of rapid snow melt and heavy rainfall) across parts of southeastern South Dakota, eastern Nebraska and western/central Iowa on 15 March 2019. Water and flooded land appear as darkest shades of gray to black on both sets of images —  remaining snow cover also appeared as darker shades on the 1.61 µm imagery. Additional information regarding the flooding is available from NWS Sioux Falls

In a toggle between Suomi NPP VIIRS Visible (0.64 µm) and “Snow/Ice” (1.61 µm) images at 1821 UTC (below),1.61 µm imagery showed the darker shades of flooding over a north/south portion of Interstate 29 that was closed from State Highway 34 (west of Glenwood, Iowa) to the Iowa/Missouri border (south of Hamburg, Iowa).

Suomi NPP VIIRS Near-Infrared "Vegetation" (0.86 µm) and "Snow/Ice" (1.61 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and “Snow/Ice” (1.61 µm) images; Interstate Highways are plotted in red, while State Highways are plotted in gray [click to enlarge]

Comparisons of Terra MODIS True Color and False Color Red-Green-Blue (RGB) images at 1720 UTC viewed using RealEarth are shown below. In the False color imagery, snow cover appears as lighter shades of cyan, while water appears as darker shades of blue.

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

Terra MODIS True Color and False Color RGB images, centered over eastern Nebraska [click to enlarge]

Terra MODIS True Color and False Color RGB images, centered near Vermillion, South Dakota [click to enlarge]

Terra MODIS True Color and False Color RGB images, centered near Vermillion, South Dakota [click to enlarge]

Terra MODIS True Color and False Color RGB images, centered near Ames, Iowa [click to enlarge]

Terra MODIS True Color and False Color RGB images, centered near Ames, Iowa [click to enlarge]

===== 16 March Update =====

Landsat-8 False Color image. centered to the east of Sioux City, Iowa [click to enlarge]

Landsat-8 False Color image centered to the east of Sioux City, Iowa [click to enlarge]

An overpass of the Landsat-8 satellite at 1706 UTC on 16 March provided 30-meter resolution False Color imagery — 2 sections of the swath are shown above and below. The RealEarth link to interactively view the image is here.

Landsat-8 False Color image. centered to the south of Omaha, Nebraska [click to enlarge]

Landsat-8 False Color image centered to the south of Omaha, Nebraska [click to enlarge]

Closer views centered at the NWS Omaha forecast office — which had to be evacuated due to flooding — and just west of Offutt Air Force Base are shown below.

Landsat-8 False Color image. centered at the NWS forecast office in Valley, Nebraska [click to enlarge]

Landsat-8 False Color image centered at the NWS forecast office in Valley, Nebraska [click to enlarge]

Landsat-8 False Color image. centered near Offutt Air Force Base, Nebraska [click to enlarge]

Landsat-8 False Color image centered just west of Offutt Air Force Base, Nebraska [click to enlarge]

River flooding in the Lower Mississippi and Tennessee River Valley

February 24th, 2019 |

30-day Precipitation and Percent of Normal Precipitation [click to enlarge]

30-day Precipitation and Percent of Normal Precipitation [click to enlarge]

A toggle between Observed Precipitation and Percent of Normal Precipitation for the 30-day period ending at 12 UTC on 24 February 2019 (above) showed a large area that received 10-15 inches of rainfall — which was 200-400% of normal — across the Lower Mississippi River and Tennessee River Valleys.

A before/after comparison of Terra MODIS False Color Red-Green-Blue (RGB) images from 25 January and 24 February 2019 (below) revealed the extensive area of flooding that resulted. Flooded areas appear as varying shades of blue on the False Color imagery (source).

Terra MODIS False Color RGB images from 25 January and 24 February 2019 [click to enlarge]

Terra MODIS False Color RGB images from 25 January and 24 February 2019 [click to enlarge]

In a comparison of Terra MODIS True Color and False Color RGB images from 24 February (below), many of the flooded rivers exhibit a tan-colored appearance in the True Color image due to large amounts of sediment suspended in the water.

Terra MODIS True Color and False Color RGB images from 24 February [click to enlarge]

Terra MODIS True Color and False Color RGB images from 24 February [click to enlarge]

A Flood Map derived using NOAA-20 VIIRS data (below) quantitatively showed the extent of the flooding. CIMSS scientists Jay Hoffman and William Straka contributed to the development of this food monitoring product.

NOAA-20 VIIRS Flood Map [click to enlarge]

NOAA-20 VIIRS Flood Map [click to enlarge]

Flood wave along the Nueces River in Texas

October 27th, 2018 |

As pointed out by NWS Corpus Christi (above), GOES-16 (GOES-East) Near-Infrared “Vegetation” (0.86 µm) images revealed an interesting flood wave moving along the Nueces River on 27 October 2018 (following a recent period of heavy rainfall).

A toggle between before (10 October) and after (27 October) Aqua MODIS False Color Red-Green-Blue (RGB) images from the MODIS Today site (below) showed dramatic differences between the amount of water (darker shades of blue) flowing along portions of the Nueces River on those 2 days.

Before (10 October) and after (27 October) Aqua MODIS False Color RGB images [click to enlarge]

Before (10 October) and after (27 October) Aqua MODIS False Color RGB images [click to enlarge]

A comparison of Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared Vegetation (0.86 µm) and Near-Infrared Snow/Ice (1.61 µm) images from 27 October (below) demonstrated the improved land/water contrast of the Near-Infrared imagery, which makes it helpful for diagnosing certain types of flooding signatures.

Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared Vegetation (0.86 µm) and Near-Infrared Snow/Ice (1.61 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared Vegetation (0.86 µm) and Near-Infrared Snow/Ice (1.61 µm) images [click to enlarge]

===== 28 October Update =====

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Vegetation” (0.86 µm) images at 1552 UTC on 27 and 28 October [click to enlarge]

A toggle between GOES-16 Near-Infrared “Vegetation” (0.86 µm) images at 1552 UTC on 27 and 28 October (above) showed the advance of the flood wave during that 24-hour period.

A comparison of Suomi NPP VIIRS Near-Infrared “Vegetation (0.86 µm) and “Snow/Ice” (1.61 µm) images from the early afternoon hours on 27 and 28 October (below) displayed these 24-hour changes at a higher spatial resolution (375 meters, vs 1 km at satellite subpoint with GOES-16). The rear edge of the flood wave (located about 25 miles southeast of Cotulla) appeared to show up a bit better in the 0.86 µm images than the 1.61 µm.

Suomi NPP VIIRS Near-Infrared

Suomi NPP VIIRS Near-Infrared “Vegetation (0.86 µm) and “Snow/Ice” (1.61 µm) images from 27 and 28 October [click to enlarge]

Finally, in a toggle between 250-meter resolution Aqua MODIS False Color RGB images from 27 and 28 October (below), the advance of the leading edge of the flood wave can clearly be seen.

Aqua MODIS False Color RGB images from 27 and 28 October [click to enlarge]

Aqua MODIS False Color RGB images from 27 and 28 October [click to enlarge]

===== 29 October Update =====

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Vegetation” (0.86 µm) images from 1552 UTC on 27, 28 and 29 October [click to enlarge]

GOES-16 Near-Infrared “Vegetation” images from 1552 UTC on 27, 28 and 29 October (above) showed the continued eastward movement of the flood wave down the Nueces River.

Heavy rainfall in Arizona from the remnants of Rosa

October 2nd, 2018 |

GOES-16

GOES-16 “Clean” Infrared Window (10.3 µm) images, 25 September – 02 October [click to play MP4 animation]

Rosa became a Tropical Storm on 25 September 2018, and reached peak intensity as a Category 4 Hurricane on 28 September. As it gradually weakened and made landfall over Baja California on 02 October, its moisture moved across the US Desert Southwest causing heavy rainfall and flash flooding — parts of Arizona received record-setting rainfall (NWS Phoenix | NWS Flagstaff), with precipitation rates as high as 1 inch in 30 minutes in the Phoenix area. GOES-16 (GOES-East) “Clean” Infrared Window (10.3 µm) images during the 8 days from 25 September to 02 October (above) showed the life cycle of Rosa.

A closer look at Rosa during that same time period is shown below. The image interval is 15 minutes, except for 5-minute imagery during a test of Mode 4 scanning strategy on 01 October (from 0000-1550 UTC).

GOES-16 "Clean" Infrared Window (10.3 µm) images, 25 September - 02 October [click to play MP4 animation]

GOES-16 “Clean” Infrared Window (10.3 µm) images, 25 September – 02 October [click to play MP4 animation]

The transport of tropical moisture associated with Rosa could be followed using the MIMIC Total Precipitable Water product (below). The moisture over southwestern Arizona on 02 October was >4 standard deviations above normal for that region and time of year.

MIMIC Total Precipitable Water product, 25 September - 02 October [click to play MP4 animation | MP4]

MIMIC Total Precipitable Water product, 25 September – 02 October [click to play MP4 animation | MP4]

The increase in deep tropical moisture was very evident in plots of rawinsonde data from Tucson, Arizona (below) — Total Precipitable Water peaked at 43.9 mm or 1.73 inches at 12 UTC on 01 October.

Plots of rawinsonde data from Tucson, Arizona 30 September - 02 October [click to enlarge]

Plots of rawinsonde data from Tucson, Arizona 30 September – 02 October [click to enlarge]