Did you know today is the last day of winter? If you check your calendar you'll see the first day of spring is March 20th. However, there is another way to calculate the seasons. It's called meteorological winter.

Meteorological winter is based on the on-set of winter-like conditions. Here in the United States, it begins December 1st and ends the last day of February. Astronomical winter is defined by the Earth's position with respect to the sun. It begins at the Winter Solstice and ends at the Vernal Equinox.

So it's your choice whether to consider tomorrow the first day of spring or wait three more weeks. With snow expected tonight, it may be easier to wait.

JC Monahan
Meteorologist, WCVB

We could have some river and stream flooding problems
later on as we head into the early Spring.
We've had record breaking amounts of moisture this February
in the Boston and Worcester areas.Boston has been soaked
with over 8 inches of liquid and Worcester over 9 inches of
liquid equivalent in rain and snow melt.

In addition, snowfalls across Northern New England
are approaching record breaking levels in many areas.
If we have a a persistent warm spell along with heavy rains,
we could have serious river flooding this Spring because of
rainfall and rapid snow melt.

Dick Albert

"Big Flakes, Small Snow...Small Flakes, Big Snow"

Have you ever heard that expression? Here's what is behind it. If you recall, late Tuesday afternoon many parts of our area had big, fat snowflakes falling. They were very big and very wet, because we were right near the rain/snow line. Often, the big flakes are a sign that snow will soon to be changing to rain, and that is what happened. When the flakes are small, they often hold less moisture, but the air is colder. So, the precipitation usually stays all snow and begins to pile up. Even though total moisture is not that high when it is very cold and snowing, there often can be a "fluff factor," meaning the snow can pile up in terms of many inches, but this type of snow is easier to shovel, plow and move around, because it is lighter in weight than heavy, wet snow.

Harvey Leonard
Co-Chief Meteorologist, WCVB-TV

Although December and February are both winter months, the same storm occurring in both months will have very different outcomes. In December, the saying goes “Give it a reason NOT to snow, and it will not”. This alludes to the fact that the ocean is still very warm and the ground is not frozen or even snow covered. However, fast-forward two months and now the February ground is rock solid and the ocean water is ten degrees colder. Now our saying goes, “Give it a reason TO snow, and it will”! Today’s storm is loaded with moisture and the potential for snow. Our recent snow and chilly morning temperatures will set the stage for most of us to briefly start as snow. However, all of these snowy factors will be fighting a mild southerly wind as the storm passes to our west later today and tonight. This will change any snow or mix to rain. Bitter cold Arctic air is on the way for the end of the week.

Joe Venuti
WCVB Meteorologist

With the recent daytime melting and the below freezing temperatures at night, black ice has been forming on area roadways. The ice that forms isn't really black, it's exceptionally clear. This allows the color of the roadway to shine through. Roads are often made of black asphalt so we call it "black ice".
The reason for it's transparency is the lack of air bubbles trapped in the ice. The more air trapped inside, the higher the reflectivity of the ice. This lack of bubbles makes it difficult to see and exceptionally slippery. Especially if the pavement is wet to begin with. You may be driving along on a wet roadway and not even realize the road surface has turned to ice until it's too late.
Black Ice will often form on bridges and overpasses first. Cold air can circulate under these structures and cool more quickly than surrounding roads.
When humidity is high and temperature are below freezing be careful and slow down.

Mike Wankum
Meteorologist
WCVB-TV

While it has been a rather stormy and wet month, we haven't had a lot of snow. So far, Boston has received 4.7" of snow in February. That's more than three inches below normal. Most of the precipitation this month has been in the form of rain. As a matter of fact, last weeks rain washed away most of the snow pack in our yards.
Today should change all that.

A storm passing to our south will bring snow with a little mix. There won't be a lot of wind and the snow should accumulate easily. This weekend will get progressively brighter and warmer so there will be plenty of opportunity to clean up from our latest round of wet weather.

JC Monahan
Meteorologist, WCVB

Boston is having an above normal snowfall winter.It has been
a little strange weatherwise with temperatutres at 63 degrees earlier this
week. But December was one of the snowiest on record.
When you add it all up, we've had 41 inches of the white stuff
so far which is 11 inches above average for this time of the year.

More snow is on the way!!. Friday looks like a slippery evening commute
with the potential of 3 to 6 inches of snow during the afternoon and evening.
This snowfall would bring the total for this season well above our winter
average of 42 inches.

Dick Albert

An Incredibly Moist February

Boston may be on its way to a record moist February. So far, precipitation has totaled 6.72" That makes this the 5th wettest February on record already.
And, we still have more time and more precipitation to go through. The wettest February on record occurred in 1984 with 7.81" of precipitation. Our next round of precipitation will probably come in the frozen variety. Yes, I'm talking about the likelihood of some accumulating snow Friday afternoon and/or night. The colder air that is moving in now will be setting the stage for the very end of the week snow threat. Meanwhile, don't forget to check out Wednesday night's total lunar eclipse, which begins (partially) at 8:43 p.m., reaches totality from 10:01 p.m. thru 10:52 p.m., and then ends shortly after midnight.

Harvey Leonard
Co-Chief Meteorologist, WCVB-TV

This winter has been a bit unusual. While we are still computing weather records on the topic, most of us can't remember a winter with this much lightning and thunder. Lightning is usually associated with thunderstorms, and thunderstorms are typically a summer and spring event. However it's certainly not unheard of. There are as many as 2000 thunderstorms occurring on the planet right now. That translates into 100-125 lightning strikes per minute on the planet Earth. While most of these due occur during the warmer months, lightning is often reported in major snow events such as blizzards and nor'easters. This year in New England we've been getting more lightning not because of big snow events, but because we've had such clashes of air masses that summer like thunderstorms have been developing. Lightning and heavy rain have plagued our forecast this winter. And yes, lightning in the winter is as dangerous as in the summer. People have been struck by lightning in the middle of winter.

Mike Wankum
Meteorologist
WCVB-TV

Our active weather this winter has led to an active pothole season. You may have noticed an increase on our city and local streets. Our dramatically changing temperatures allows water in and around the pavement to expand and contract. In addition, heavy precipitation, like yesterdays torrential rain, washes away loose fragments creating even larger potholes for drivers and pedestrians to contend with.

Our rising and falling thermometer will continue as temperatures climb into the 40's today, followed by arctic air Saturday. Much warmer air and potentially heavy rain Monday will only make our pothole problem worse.

JC Monahan
Meteorologist, WCVB

Winter in New England is the toughest time of the year
to make an accurate forecast Over 50 per cent
of the storms are not straight rain or all snow.

Many of our winter storms are a combination of
snow,sleet,freezing rain and rain.The forecasting of the
location,timing and amounts of these different precipitation
types is our biggest forecasting challenge.

We do have help from doppler radar and better
computer technology,but much of it still comes
down to experience and forecasting knowledge.

So the next time the forecast is off by a few hours and
a few inches of snow,remember,it's not an exact science
and we are trying our level best to give you the best forecast
possible.

Dick Albert

Have you ever been driving in February sunshine,suddenly the sky turns dark, the wind begins to howl and within seconds you can't see the hood of your car? Welcome to the world of snow squalls. Snow squalls can produce almost blizzard like conditions for a few moments. The squalls are created by a blast of cold air racing through the region. Lifting moisture at the surface and building cumulonimbus clouds. They are the winter equivalent of summer thunderstorms. In the summer these thunderstorms would build to 20-30,000 feet, however in the winter these squalls usually are only about 5-10,000 feet. Despite their low altitude they have a lot of vertical motion within the clouds. That's why lightning and thunder are common with these systems. They usually only last about 15-20 minutes so heavy accumulation of snow is unlikely, but because of the whiteout conditions, they are especially dangerous to drivers.

Mike Wankum
Meteorologist
WCVC-TV

A devastating outbreak of tornadoes occurred Tuesday in five southern states. More than fifty people were killed, making it the nation's deadliest occurrence of tornadoes in more than twenty years.

Damage is still being analyzed but preliminary reports estimate the storms to have wind speeds between 111 and 165mph. Tornadoes are rated using the Enhanced Fujita Scale. This is an analysis of the severity and type of damage done by the storms. The scale goes from zero to five with five assessing winds of more than 200mph.

In the last 24 hours,we have experienced a potpourri of
weather types. A mixed bag of sleet, freezing rain and snow flakes
have moved through the area.

There is a big difference between sleet and freezing
rain.Sleet is small pellets of ice that bounce as they
hit the ground and the ice pellets do not stick to objects. Freezing rain
is liquid that falls as drops and freezes to objects upon
contact. Freezing rain can cause major problems if more than
one half of an inch of ice forms on branches,trees,sidewalks
and other areas.These elements can cause some of our biggest
winter problems.

Dick Albert

This is the time of year that thousands of people become affected by SAD or Seasonal Affective Disorder. It typically occurs during the winter months when daylight is at a minimum. Although not fully understood, we do know that sunlight on the skin produces vitamin D which aids the absorption of many nutrients that keep our body chemicals in balance. The best cure or prevention is 30 minutes or more of direct sunlight each day…just the excuse you need to take that break from the daily grind. However, the weather will not cooperate over the next few days with lots of clouds and rain in the forecast.

Joe Venuti
WCVB Meteorologist

In case you missed it, on Saturday Punxsutawney Phil predicted 6-more weeks of winter. Every February 2 Ground Hog Day allows for a little fun with long range forecasting. Awakened at sunrise, the 15-pound woodchuck is held up to the crowd on Gobbler's Knob. Legend has it that if it's overcast and the Ground Hog doesn't see his shadow, winter will come to a quick end. If the sun is out and a shadow is cast, 6-more weeks of winter will ensue.
While it's all done in fun and is certainly a way to break up the winter in Pennsylvania it's not a very accurate forecast. Researchers have determined Phil's is only correct about 38% of the time. Animals do have a highly developed sense of weather for short term forecasts. Perhaps 1-3 hours, but no scientific study has been able to link animal behavior to long range weather patterns. So the rings of wooly caterpillar, the bushiness of squirrel's tail or the shadow of a ground hog won't help you with long range plans. And besides, with our recent mild weather 6-more weeks this wouldn't seem like winter anyway.

Mike Wankum
Meteorologist
WCVB-TV