June 29th, 2011
GOES-13 0.63 µm visible channel images (click image to play animation)
McIDAS images of GOES-13 0.63 µm visible channel data (above; click image to play animation) showed that there was still a great deal of ice remaining in much of Hudson Bay, Canada on 29 June 2011. However, it is interesting to note the motion of the ice on the high-speed animation — some of the ice features move in one direction, stop, and then move in a nearly opposite direction during the course of the day. A ridge of high pressure was in place across the region, with surface winds generally from the northeast over the eastern portion of Hudson Bay, and surface winds from the southwest over the western portion of Hudson Bay (ASCAT winds).
A comparison of AWIPS images of the MODIS 0.65 µm visible channel and a false color Red/Green/Blue (RGB) image (created using MODIS bands 01/07/07 as the R/G/B components of the image) confirmed that it was ice occupying the majority of Hudson Bay — ice features (as well as glaciated clouds) appear as shades of red on the false color image. According to an analysis performed by the Canadian Ice Service, this consisted of thick to medium first year ice.
MODIS 0.65 µm visible channel image + MODIS false color RGB image
Toward the end of the GOES-13 visible channel animation above, the hazy signature of smoke aloft could be seen drifting south-southwestward over the far eastern part of Hudson Bay. This smoke — a result of wildfires burning in northern and western Canada — also showed up well in a MODIS true color RGB image (below) from the SSEC Direct Broadcast site.
MODIS true color RGB image
An AWIPS image of the MODIS Sea Surface Temperature (SST) product (below) revealed that SST values were still in the 30s F (darker blue color enhancement) across much of Hudson Bay, with a few pockets of warmer water seen in various locations.
MODIS Sea Surface Temperature product
CIMSS participation in GOES-R Proving Ground activities includes making a variety of MODIS images and products available for National Weather Service offices to add to their local AWIPS workstations. The VISIT training lesson “MODIS Products in AWIPS” is available to help users understand these products and their applications to weather analysis and forecasting.
June 27th, 2011
MODIS Land Surface Temperature product
Record heat was experienced across parts of the Texas and Oklahoma panhandle regions and southwestern Kansas on 26 June 2011 — all-time record high temperatures in Texas included 117ºF at Childress (record tied), 113ºF at Borger, 111ºF at Amarillo, and 110ºF at Dalhart; in Oklahoma, 113ºF at Gage; and in Kansas 110ºF at Dodge City. An AWIPS image of the MODIS Land Surface Temperature (LST) product in the late morning at 16:52 UTC or 11:52 am local time (above) showed a large area exhibiting LST values of 125-130ºF (darker red color enhancement) at that time (although shelter air temperatures 5 feet above the surface were only in the 102ºF to 104ºF range).
GOES-13 3.9 µm shortwave IR images (below; click image to play animation) showed how after sunset the areas with drier air (lower dew points) tended to cool off faster than adjacent areas with more moisture in the air (higher dew points).
GOES-13 3.9 µm shortwave IR images + METAR surface reports (click image to play animation)
Farther to the west, a large wildfire was burning near Los Alamos National Laboratory in New Mexico. A sequence of daytime GOES-13 0.63 µm visible channel images followed by night-time GOES-13 3.9 µm shortwave IR images (below; click image to play animation) revealed a very large smoke plume spreading northeastward during the day on 26 June, along with a very large fire “hot spot” (black to yellow pixels) on the shortwave IR images. The large smoke plume was still apparent on the first few visible images on the next morning (27 June).
GOES-13 0.63 µm visible images + GOES-13 3.9 µm shortwave IR images (click image to play animation)
A comparison of 1-km resolution POES AVHRR 0.63 µm visible channel and 3.74 µm shortwave IR channel images (below) showed a better view of the fire hot spot and associated smoke plume at 01:32 UTC.
POES AVHRR 0.63 µm visible channel and 3.74 µm shortwave IR channel images
June 23rd, 2011
MODIS 0.65 µm visible channel and 2.1 µm near-IR "snow/ice channel" images
AWIPS images of 1-km resolution MODIS 0.65 µm visible channel and MODIS 2.1 µm near-IR “snow/ice channel” data on 23 June 2011 (above) demonstrated the utility of the snow/ice channel to help highlight areas of potential flooding — because water is a strong absorber at the 2.1 µm wavelength, it appears very dark in the snow.ice images. The Souris River located in north-central North Dakota stands out in the images, along with the Missouri River to the southwest.
A comparison of 250-meter resolution MODIS true color and false color images (below) showed greater detail of the flooded areas on the false color image, as well as the fact that a great deal of sediment was flowing into the Missouri River and even into the western portion of Lake Sakakawea.
MODIS true color and false color Red/Green/Blue (RGB) images
A comparison between MODIS false color images on 29 June 2010 and 23 June 2011 (below) showed the dramatic change in the Souris River, as well as in the Missouri River southwest of Williston, North Dakota. In June 2011 historic flooding was occurring in the city of Minot along the Souris River.
MODIS false color RGB image comparison: 29 June 2010 vs 23 June 2011