March 31, 2018

Bipolar Weather

Current Conditions:

Temperature: 20 °F
Dew Point: 6 °F
Winds: W 15 mph
Pressure: 1023.0 mb
Visibility: 10 miles

Today started off mild with a temperature of 27 ° and winds N at 14 mph. The dew point was also 27 °F which means the dew point depression was 0 and the air was completely saturated. Early this morning it was still snowing and the snow was heavy and wet. By mid-morning there was light snow and fog in the Eau Claire area. This is the result of a low pressure system moving through from the north. What a great way to welcome in April. And no, this was unfortunately not an April fool's joke. Later in the day the snow stopped and the sun came out for a few hours. Figure 1 shows the temperature, winds, and pressure as the day progressed.

Figure 1. Weather overview for March 31, 2018.

The top graph shows the dew point and temperature being the same early in the day and by the end of the day they had diverged and lowered, a consequence of the low pressure system moving south and a high pressure dome moving in. The barometric pressure also tracks the low pressure system with a low around 6:00 to 7:00 AM. The wind speed increased after the low pressure system moves over because of the force of the system moving away. Wind direction also switches with winds now coming out of the north bringing the cooler temperatures. Figure 2 shows the cooler temperatures that have settled over Wisconsin following the low pressure system.

Figure 2. Temperature map of the United States on March 31, 2018.

Previous Prediction

Yesterday I predicted snow and overcast skies which did happen this morning. However the system moved south quickly and skies were clear later in the day.

Prediction

For tomorrow I predict the high pressure system will stay in the area (figure 3) and temperatures will be lower, in the 30s with partly cloudy skies.

Figure 3. Surface map of the United States on March 31, 2018.

Although tomorrow will be nice, another snow storm is brewing and could hit on Monday leaving another 1-3 inches of snow. Oh how wonderful a Wisconsin spring is...