Stages of Winter

     Winter in southeastern Pennsylvania has five predictable, but arbitrary, stages, a beginning, when that season becomes more intense, mid-winter, when daylight per day gets noticeably longer, and its ending and overlapping with early spring.  Each stage doesn't have a precise date, but each occurs about the same time annually.
     Winter truly begins around the tenth of November.  At this time, the weather could still be warm in the afternoons, but the amount of daylight each succeeding day continues to shorten.  Most leaves have died and fallen from their twig moorings, most other vegetation is dormant and the majority of bird migrations are already completed by that time.  And the "look" and "feel" of winter dominates the landscape.
     Around the tenth of December, the weather turns much colder, often bitter cold, and there will be few, if any, warm afternoons.  Winter weather is really upon us.  And by now, periods of daylight each day are as short as they are going to get, with sunset being about 4:40 PM for a few weeks.  Snow that falls now usually remains for some time.          
     December 21st is mid-winter.  Now the sun "won't travel any farther south" and daylight per day will get no shorter.  In fact, daylight each day now will get longer by a couple of minutes each succeeding day, but a few weeks will pass before we can readily see a significant difference in the lengthening amount of daylight per day. 
     Local weather is at its coldest around the middle of January.  Cold fronts with frigid temperatures, sunlight and low humidity roar south.  High temperatures per day might be in the teens or lower.  Snow and ice are not going to melt.  But in spite of the intense cold, daylight each succeeding day gets noticeably longer, perhaps taking a bit of the sting from the bitter cold in our imaginations.  And that lengthening of daylight each day is the first promise that the "sun is coming north again", bringing spring with it.  
     And around the tenth of February, spring begins in the local area.  Daylight per day is much longer than it was in December, but wintry weather could strike at any time.  However, that weather can vanish just as readily in the warmer sunshine.  There is a constant struggle between mild weather and cold weather through February.  Wildlife and vegetation in the midst of that contest have to be adaptable and tough, which they are.  Geese and swans starting their migrations north at this time.  Permanent resident, small birds, including tufted titmice, song sparrows, house finches and mourning doves, sing territorial songs during warm February afternoons.  Male wood chucks prowl across the still austere landscape in search of mates during the day and male wood cocks dance and sing for mates each dusk.  Meanwhile, skunk cabbage, snow drop, winter aconite and chickweed flowers are in bloom by this time, sometimes under a blanketing, protective layer of snow.  The "feel" of spring is in the air.
     All these arbitrary parts of winter overlap each other and are never precisely on time.  But they are undeniable.  Watch for them during successive winters to come.