Wide temperature swings — with variations of more than 50 degrees in a 24-hour period — have been the norm for the area lately.
Last week heavy, blowing snow and frigid temperatures gripped the Wyoming Valley as a winter storm closed schools and caused numerous delays. On Sunday the thermometer approached 40 and rain melted most of the snow.
Temperatures were in the 50s on Monday morning, and the lingering rain felt like a spring shower. Those warm temperatures, however, will give way to dangerous sub zero temperatures today.
David Nicosia, a warning coordination meteorologist at the National Weather Service, spoke about the recent trend of fluctuating weather and what can be expected in the near future.
Q. It was bitterly cold on Friday night/Saturday, but mild on Sunday and Monday. Now, sub-zero temperatures are in the forecast for today. Why is this fluctuation of temperatures happening?
A. “There is an unusual amount of cold air in southern Canada and the north central U.S. Because of this, storm systems have more energy to tap into and become stronger, plus the source region of the bitter cold air is much closer than usual.
“Temperature differences are what ultimately determine how intense winter storms become. These stronger winter storms lead to stronger winds, which can rapidly change temperature.
“Strong south winds rapidly brought milder air to Pennsylvania as a storm tracked west of our region. Now we are getting strong west winds as the storm has passed to our north and east. These west winds were blowing bitterly cold air back into the region.”
Q. What will cause the dramatic cool down that is set to grip the area this week?
A. “Very strong west winds and a bitter cold air mass much farther south than usual. Temperatures are in the minus teens directly to our west in Indiana and Illinois. West winds are driving this air toward Pennsylvania.”
Q. Rainfall has been fairly normal throughout December and up until now. How common is rainfall in December?
A. “About 50 percent of all storm events bring rain to Pennsylvania in the winter months. Remember, the average high temperature in December, January and February for the Wilkes-Barre/Scranton area is in the mid 30s and the average low is around 20 degrees. This means that 50 percent of the time, temperatures can be even higher, which leads to rain instead of snow.”
Q. With the combination of rainfall and melting snow, is flooding a concern?
A. “Not at this time. However, anytime our area builds up a big snow pack and we are looking for rain and snow melt, flooding is a concern and everyone should be prepared in case flooding occurs.”
Q. What can the Wilkes-Barre area expect over the next couple of days?
A. “Temperatures will fall to about 5 degrees below zero this morning with west winds up to 20 mph and gusts over 30 mph. Wind chill temperatures will fall as low as minus 25 degrees. Temperatures during the day Tuesday will struggle to reach 10 degrees as wind chills remain dangerously cold all day.”
Q. What are some hazards that come with sub zero temperatures? What can people do to protect themselves?
A. “Frostbite and hypothermia. Stay indoors if at all possible, the cold could become life-threatening if you are outdoors long enough and not properly dressed.”