Something we haven’t seen much of this season is a blast of icy cold Arctic air. That may soon change as we get into late Saturday and the beginning of next week. Of course if that happens, something else we haven’t seen much is the lake-effect snow making machine in high gear. That said, both cold and snow appear more likely as we head in to next week.
Take a look at the computer forecast models that meteorologists use to help forecast the weather. This map shows temperatures on Saturday morning about 5,000 feet above the surface around -2 Celsius. That means temperatures at the surface will be around the mid 30s. However, This image shows temperatures at 5,000 feet on Saturday evening sharply colder as the Arctic air begins to seep southward in to Michigan. Temps are progged to be around -18 to -20 Celsius by that time (note the colder colors over Michigan). These types of maps are especially helpful in determining the movement of air masses above the surface without any ground interference or contamination. Unfortunately, the models are in degrees Celsius and not Farenheit, which make it a little tougher for the average user to understand and convert. Temperatures (on this map) by Sunday evening are expected to be at -20 Celsius about 5,000 feet above the surface. If this model verifies, that would create surface temperatures of around 20 degrees. The Arctic blast continues on Monday evening with this map showing -22 to -24 Celsius, and a solid -24 Celsius still over the state on Tuesday morning.
Temperatures that cold 5,000 feet above the surface will likely mean air temperatures at the surface in the upper teens/near 20, with the possibility of heavy, persistent lake-effect snow. Of course, the air mass would have to be moist enough, and any temperature inversion would need to be high (above 5,000 feet) for appreciable snow to occur. An inversion is when the temperature increases somewhere above the surface instead of a normal decrease. When inversions are high, snow showers have more room to grow (vertically) and the snow can start piling up quickly. When inversions are low (5,000 feet or less), heavy snow is unlikely because a lid is kept on the atmosphere to prevent vertical growth. This situation is similar to severe weather in the summer. A temperature inversion (or cap) can prevent severe weather if the cap is strong and goes unbroken. However, a broken cap can result in explosive severe weather during the warm season months. Click here to read more about temperature inversions.
You can click here to get an easy-to-understand lesson on lake-effect snow. While Arctic air is the catalyst for lake-effect, it is NOT the only factor. Others (mentioned above) are equally important, as is the wind speed and direction. West winds tend to drag snow further inland, while northwest winds dump the heavier snows along/west of U.S. 131. North winds favor locations along the immediate lakeshore (Big Sable/Little Sable Point) for the heaviest snow. So while the “potential” is certainly there for favorable accumulating lake-effect snow next week, several other factors must work in conjunction with the Arctic air.
Take a look at the six to 10 day temperature outlook from the Climate Prediction Center. A bullseye of below normal is expected. The eight to 14 day temperature outlook is also below normal for the Great Lakes with a bullseye overhead. As it stands, Grand Rapids is currently running a snow deficit of 30.2 inches so far this season. We are now in the top five least snowiest seasons of all time with only 9.6 inches of snow recorded. Here are some other interesting numbers and stats:
- The all time record was set back in 1906 at 7.2 inches for January 15, and a season snowfall total of only 20 inches.
- Second was 1932 with 7.7 inches of snow by this date.
- Third was 1947 with 7.9 inches of snow by this date.
- Fourth was 1949 with 8.6 inches of snow by this date.
- Fifth is 2013 with only 9.6 inches recorded thus far.
You can always check temperatures, radar, satellite, or the complete 7-day forecast by clicking over to www.fox17online.com/weather.