Past IEM Features tagged: daily
Our current rebound in temperatures to levels well above freezing are certainly a nice break from the recent few weeks of cold weather. Climatology says that the middle of January is the coldest time of the year, but climatology can be computed different ways. The featured chart presents three daily temperature climatology metrics. The National Climatic Data Center (NCDC) produces 30 year normals which are updated every ten years. The chart shows the most recent two iterations of that product as well as the simple daily average of long term observations. The 1971-2000 product was provided in whole degree Fahrenheit, so that is why it jumps up and down on the plot. It is interesting to note the difference between the 1981 product and the other two metrics.
Tags: daily temperatures
The day with the least amount of daylight is also the start of the winter season. This at first may seem counter-intuitive as the sun is the energy source for heating the ground which then heats the air. We have about another month yet to go before we see the coldest average air temperatures as shown by the featured chart presenting the daily climatologies of air and soil temperatures along with daylight length. You can see that none of these curves exactly line up with their maximums and minimums shifted in time slightly.
Tags: daily climate soil daylight