Near-record March temperature in South Dakota
MODIS 0.65 µm visible channel image + MODIS Land Surface Temperature product
On 18 March 2012, the maximum temperature at Winner, South Dakota (station identifier KICR) reached 92º F (33º C), which was just shy of the State’s all-time record high temperature for the month of March (which was 94º F or 34º C, set at Tyndall in 1943).
An AWIPS image comparison of MODIS 0.65 µm visible channel data with the corresponding MODIS Land Surface Temperature (LST) product (above) showed pockets of very warm LST values in the 95-105º F range (darker red color enhancement) across parts of South Dakota at 19:10 UTC (1:10 pm local time). Differences in soil type and vegetaion density can contribute to higher LST values — and there is no direct 1:1 correspondence between LST values and air temperature values measured in an instrument shelter at a height of 5 feet off the surface. Daily record high temperatures were also set on 18 March at other locations in central and eastern South Dakota: Pierre (88º F), Sioux Falls and Aberdeen (85º F), Sisseton and Watertown (82º F), and Mobridge (81º F).
Land surface temperature values were not available in the immediate vicinity of Winner at the time of the MODIS images, due to patches of thin cirrus cloud over that area — the cloud mask prevents the calculation of LST products in cloudy areas. These patches of thin cirrus clouds could be seen as colder IR brightness temperatures (yellow to green color enhancement) in the MODIS 11.0 µm IR channel image (below). The warmer north-to-south oriented line located to the northwest of Winner was the burn scar from the Okreek fire which burned on 05 October 2011.
MODIS 11.0 µm IR channel image