Unusual Temperature Surge
The picture below is a snapshot of my Davis WeatherLink strip charts for 7–9 January 2006. The highlighted region shows a marked temperature rise as the 8th was closing out, followed by a more normal temperature drop throughout the rest of the night. Temperature remained steady or slowly falling during the day of the 9th.
In the top chart, the red line is the outdoor temperature, the blue is the wind chill, and the green is the dew point. In the next chart, the red is the wind direction, and the blues are the wind speed and hi wind. In the third chart, the cyan line is the outdoor humidity (the other two lines are indoor temperature and humidity). In the bottom chart is the barometric pressure (the blue line would show precipitation if there had been any).
At 23:20, the temperature was 33.2° and by 00:00 it had jumped to 45.5°, where it leveled off briefly before topping out at 47.6° at 00:55. At the same time, the wind kicked up and swung from the east to a west-southwesterly flow. Even though the dew point had a sharp rise, too, it was not enough to keep up with the temperature and the humidity dropped rapidly.
Once the pressure began to rise, the temperature began to fall, and everything slowly calmed down.
By the way, we had some brief snow showers on Friday (the 6th), but never had more than a trace on the ground, even on mulch.
awc 2006-01-10 18:32
|  IN-AL-99 |
