Blog

48 Articles

Weather Blog

No more snow, right?

Posted on

The sun is peaking through the clouds, and the ice and snow are melting. Feel free to join me in a loud “hooray!” As my mother, a true Yankee, said to me this morning, “The snow is pretty when it first falls, but by the third day, it’s just an ugly mess.”

winter flower

A winter flower covered in snow and ice just off Niki’s front porch.

Now that the temperature has risen above freezing and will stay there for the next week or so, does that mean our winter weather is over?  The question I heard today was, “That was our one big storm, right?”

I have to answer honestly and say probably not, based on the climatology for our area. While meteorologists remind you to be vigilant by saying that it “only takes one storm,” that doesn’t mean you only get one storm per year. In fact, the Triangle area is more likely to see wintry mixes in early February and early March than in early January.

I did take a look at the Climate Prediction Center’s outlook for the next week, two weeks, one month, and three months, and our area does have a better chance than usual to see warmer than average temperatures through the rest of the winter and into early spring. So, maybe this past weekend’s storm was it for us. Maybe.

You see, this is where I have to say that it only takes one storm. While the next three months really could produce warmer than average temperatures overall, there still could be a day or two or three embedded in that time span with another perfect setup for another wintry mess. In fact, the GFS model is showing a possible winter storm taking shape on January 26.

Do I trust long-range models to be accurate that far out? No. Please don’t take that one sentence and run with it as if the next winter storm is a forgone conclusion. My point is that between now and that date, we could see a long stretch of warmer than normal temperatures, and then suddenly have a cold snap and snowfall for a day. Rebounding back to warmer than normal within a day or two afterward would increase our three-month average despite having one more frigid winter storm embedded in those months.

If you’re a snow lover, it may be good news to hear that we could have more this season. If you’re not a snow lover, it may be a bummer. No matter what your preference, if you have lived in Wake Forest for a while, you know that winter typically lasts through early March here regardless of what a rodent may predict in February. I’ll wait a few more weeks before I get on that soap box.

Weather Blog

Snow may be the headline, but cold is the story

Posted on

Snow is in the forecast, and much of North Carolina is under a Winter Storm Warning from this evening through tomorrow evening. Of course, that means everyone is asking meteorologists how much snow we are going to get.  Hardware stores are running out of shovels and ice melt, and there is a run on bread, milk, and sleds across the area. Depending on your feelings about winter weather, you’re either filled with excitement or dread about the possibility of 4-9 inches of the white stuff.

The attention to the precipitation is important, but there is an element of the story that I worry some people are missing: It is about to get bitterly cold by our standards.

If you are planning on being outside this weekend because you’re working or you love the snow or maybe you just have to supervise your children while they are playing in it, keep in mind that our temperatures are not likely to rise above freezing until Monday or Tuesday afternoon.  Add breezy conditions to the cold, and you have some biting wind chills to contend with.

On Saturday, our high will be in the upper 20s with winds at 5-15 miles per hour, gusting to 25 miles per hour at times, creating a wind chill in the lower teens. Sunday won’t be much better with a high near 30 degrees and a breeze in the early part of the day at 5-10 miles per hour, resulting in a possible wind chill in the upper teens.

Many relocated northerners might be used to this, but in these parts, we don’t see over night lows in the single digits and daytime wind chills in the teens very often. It is a different kind of cold that requires layers of warmth and limited time outside.

However you plan to spend this weekend, stay safe and warm, and don’t forget to check on any neighbors that might need assistance due to age or illness.

NOAA Wind Chill Chart

NOAA’s Wind Chill Chart shows what the temperature will feel like based on the actual air temperature and wind speed.

Weather Blog

Snow is in the forecast this weekend

Posted on

As of 11:30 this morning, the National Weather Service had issued a Winter Storm Watch for much of central North Carolina.

NWS WSW map

The areas under a Winter Storm Watch issued by the National Weather Service as of 11:30 AM, January 5, are highlighted in blue. The storm totals are subject to change.

Wake Forest could see as much as four to six inches of snow, but that amount is still subject to change.  The current forecast track and timing show the storm starting here as rain Friday evening and transitioning to snow Friday night. The temperature is not likely to rise above freezing on Saturday, and precipitation will continue to fall through at least early afternoon.  Actual snowfall totals will depend upon how long that rain to snow transition takes to happen.

Many of the forecast models are showing the freezing line somewhere in the vicinity of the southern part of the Triangle.  If that line shifts northward, we will get more rain – cutting into possible snow accumulation.  If it shifts southward, we will see more snow.

Another factor in snowfall amounts is exactly what path the low pressure center takes. Any waver from the current forecast path and we could see more moisture or less moisture. More moisture could mean more snow.  Less moisture could leave us totally dry all together, but the chances of that happening are increasingly slim with each model run.

In addition to the initial snowfall, black ice will be a lingering hazard.  High temperatures are not expected to get much above freezing on Sunday and Monday.  Any liquid that occurs from daytime melting on the roadway will refreeze quickly.  In shadowy areas, it’s possible that there won’t even be any melting. So, the cold temperatures are important considerations when looking at possible hazards from this storm.

What do you do if you have plans for this weekend?  Stay up to date on the forecasts as the situation unfolds over the next 48 hours.  A Winter Storm Watch means travel is expected to become hazardous. While the State Department of Transportation has been brining the roads since yesterday, if there is enough rain before the transition to snow, some or much of that brine could be washed away. Also, brine does not mean that snow will not accumulate; it just slows the accumulation process.

I can tell you that personally, I have changed my plans for the weekend and expect to be fully hunkered down for the long haul Friday night.

Weather Blog

What low forecast confidence means

Posted on

If you read this morning’s forecast discussion from the Raleigh National Weather Service Office, it actually says that the forecasters have low confidence in the forecast “from Friday night onward.” I noticed because I also have low confidence in the forecast, and I was looking to them for their take on what the models are predicting. Does this mean that we aren’t good at what we do? No, on the contrary, it means that we are good enough to know when to admit that the computer models are giving us contradictory information.

GFS dominant p-type

This map shows the dominant precipitation type for Saturday evening according to this morning’s GFS model run. The GFS is just one model ofseveral that meteorologists consider when making a weather forecast. In this map, blue = snow, purple = sleet, red = freezing rain, and green = rain.

Meteorologists do not look at just one computer model when making a forecast because that would be foolish. There are numerous weather prediction models, and each has its own strengths and weaknesses.

These models are created by taking observations from current weather, trends from those observations, complex mathematical equations, and some basic assumptions about the atmosphere and using high speed computers to calculate the most likely outcomes. The current weather observations and the math equations may be basically the same for each model, but the remainder and the resolution can vary, which is why meteorologists look at each one, study each one, and do their best to understand each one’s strengths and weakness.

When all the models show basically the same potential outcome – in other words, their prediction – it is easy for meteorologists to have high confidence in our forecasts.  When the models vary greatly in their outcomes for the same time period, then we are vexed – sometimes horribly. Those are the times when some forecasters lean on intuition and past experience and others just shake their heads.  Most of us will be intellectually honest with you and say that we are not totally sure what will happen and when.

In the case of this coming weekend, our confidence is low because one model keeps our atmosphere pretty dry until late Saturday while the other has precipitation starting Friday night.  Both have the temperature pretty close to freezing, and that makes deciding whether to mention snow or stick with rain difficult when one degree in either direction makes a huge difference in what type of precipitation will fall.

Until the models start to show some agreement, the smartest thing we can say is that we could see wintry weather this weekend, but we aren’t yet sure when or how much. It’s smart because it’s honest, but honesty doesn’t necessarily sell advertising. Flashy, grocery-run inducing headlines do.

Weather Blog

Weather & Maps Go Together Like PB&J

Posted on

As I sat here, eating my lunch at my desk and reading weather news from last week that I had not had time to read until the quiet Friday before Christmas weekend, a thought occurred to me: weather and maps go together like peanut butter and jelly. You can appreciate each separately, but without one or the other, you could be missing out.

Ain Sefra map

Google Map of Ain Sefra, Algeria, and Yuma, Arizona

One of the big weather headlines last week was about a rare snow that fell over the desert in northern Africa. NASA’s Earth Observatory highlighted the story with a satellite image of the whitened area around Ain Sefra, Algeria, at the edge of the Saharan Desert. The last recorded snow there was in February of 1979, so it truly is a rare occurrence. The combination of dry desert climate and its location in relation to both the equator and the Atlantic Ocean play a part in the area’s lack of regular snowfall, but without a map, how would we know those factors?

Take a look at the Google map above. The pinned location is Ain Sefra, and the line drawn from there to southern Arizona is along the latitude 32.75 degrees North. The line crosses the southern United States through areas that do not normally see snow, but do get some on rare occasion, and it ends in Yuma, Arizona.

Both Yuma and Ain Sefra are arid regions, and some might blame their distance from the equator.  Of course, they would be mistaken.  Georgia, Alabama, Mississippi, Louisiana, and eastern Texas fall along the same parallel and are far from desert-like.  The difference between those southeastern states and the southwestern states has to do with ocean circulation almost as much as their lack of white Christmases has to do with their distance from the equator.

Ocean Circulations Map

NOAA’s Major Ocean Circulation map. The blue arrows represent cooler water; the red arrows represent warmer water.

You can see on NOAA’s map of major ocean currents that both the Atlantic Ocean and the Pacific Ocean have currents that affect the land masses that border them.  Those currents circulate generally clockwise in the Northern Hemisphere bringing warm water to the lands to their west – like the east coast of the United States – and cooler water to the lands to their east.

Those currents explain why Ireland and the United Kingdom have similar weather to our Pacific Northwest, and they help explain why Arizona and southern California have a climate similar to Saharan Africa’s.

Of course, geography also plays a role in a region’s long-term weather conditions.  Mountains, large lakes, etc., must be included when considering climate, and those can be seen on some types of maps as well.

My point is that if you take the story – or worse, just the headline – at face value without putting it into context, you miss a chance at full comprehension.

Weather Blog

Common misconceptions about winter

Posted on
snowy porch

View of the author’s front porch from inside after a late winter snowfall on February 26, 2015

On Wednesday at 5:44 a.m. Eastern Standard Time, residents in the northern hemisphere will experience Winter Solstice. Despite popular thought, the solstice is not the entire day. It’s actually that one instant with the sun passes directly over the Tropic of Capricorn. In that same moment, the southern hemisphere has its Summer Solstice. For global clarity, a better term is “the December Solstice.”

Many think that Winter Solstice is the day with the least amount of daylight, and that’s not necessarily true either. Depending on your perspective, the truth may actually be good news. Today is the shortest day of the year, or the longest night if you prefer.

The sun rises at 7:21 a.m. both today and tomorrow, but today’s sunset is at 5:04 p.m., while tomorrow’s is at 5:05 p.m. That’s right – the days start getting longer tomorrow!

You might think that with more sunlight, the days should start getting warmer, too. That assumption isn’t quite right either, although the forecast tomorrow just happens to be for warmer and sunnier weather. The coldest day of the year in our area is January 19 with an average low of 30 degrees Farenheit and an average high of 49 degrees.

Depending on how you look at seasons, Wednesday could be considered the start of winter.  It is astronomically anyway. However, meteorologists and climatologists consider December 1, the first day of winter, which would make that coldest day – January 19 – pretty close to Midwinter’s Day.

Sometimes celebrations of seasons are all about perspective. As for this southern girl, I will celebrate in late spring when the weather turns consistently warmer again.

Weather Blog

Winter Weather Preparedness Week: get involved

Posted on
By Niki Morock, Meteorologist

You might have heard that this week has been declared Winter Weather Preparedness Week in the state of North Carolina by Governor Pat McCrory.  If you follow the local National Weather Service offices, NC’s Department of Public Safety’s Emergency Management Office, Ready NC, or any other state government agencies concerned with public welfare, you have probably started seeing informational posts about the challenges of winter weather forecasting in North Carolina.

I could add to the topic, but I think they have it covered pretty well.  Instead, I want to point out how important being a proactive member of your community is, especially when it comes to weather emergencies.

While the local, state, and federal government are tasked with emergency management and official response, true preparedness starts with individuals and families in their own homes.  Are you prepared for a winter weather emergency?  What does being prepared actually mean?

View of the December 26, 2010, snow storm from the author’s front porch.

The first step in readying for a potential disaster is to know what threats you may face.  Winter storms can bring snow and ice to our area, and those hazards can lead to power and other utility outages.  Prolonged power outages can make daily activities that we take for granted difficult, warmth hard to maintain, and food hard to preserve.  Snow and ice can also make travel difficult for everyone including first responders and utility workers.

Considering those two basic points, ask yourself if you have batteries, candles, and a safe way to keep warm.  Do you have enough easy-to-prepare food and water to last three to seven days?  Do you have a basic first aid kit?  How about a reliable way to receive information such as a hand-crank or battery operated radio?  Is there enough gas in your vehicle in case you absolutely need to leave your home to find better shelter?  Other supplies you may need in a winter weather emergency include rock salt or ice melt, a shovel, an ice scraper for your car’s windows and a way to remove all of the snow and ice from your car before traveling.  You can check ReadyNC.org for a full list of what should be in an emergency preparedness kit.

Once you have your own house in order, think about your neighbors.  Do any of them have special needs?  Is there an elderly person you should check on, or family with small children that might need extra assistance?  Do you even know?

There was a time when neighbors talked to each other, really knew each other, and helped each other out.  These days, there are whole neighborhoods that seem to limit their interactions amongst themselves to a nod and a wave.  While it may seem nostalgic to ask how well you know the people in your neighborhood, those people are your immediate community and ideally should be the ones who come together first in an emergency.

You can go a step further in your preparedness and take a CPR course or join the Citizen Corps or a Community Emergency Response Team (CERT).  CERTs train in several types of emergencies including fire, medical, and search and rescue operations.  They help fill the gaps in emergency response that may happen during an extreme disaster when resources and the availability of police, fire, and emergency medical personnel are limited.

The goal of Winter Weather Preparedness Week each year is to remind people of the seasonal hazards we may face in the coming months.  I challenge you to do more than just read the articles.  I challenge you to take responsibility for your personal preparedness and think about how to get more involved in your community’s preparedness as well.

Weather Blog

Arctic blasts in December

Posted on
By Niki Morock, Meteorologist

The question on everyone’s mind today seems to be “How cold will it really be this weekend?”  My answer is “pretty darn cold.”  Normal high temperatures for this time of year are in the upper 50s, and on Friday and Saturday, the high is forecast to be around 40 degrees.  Arctic blasts for this time of year are unusual, but not unheard of.

Do you remember where you were on December 4th and 5th, 2002?  If you were in western and central North Carolina, you might.  On those dates, we had a record breaking winter storm.  In fact, by the time it was all over, Raleigh received the most freezing rain from a single storm since 1948 according to a summary on the State Climate Office of North
Carolina’s website.

Ice accumulation in 2002 storm

Freezing rain accumulation map from the National Weather Service Raleigh Office for the December 4-5, 2002 storm

The initial setup for the event was similar to what we expect at the end of this week as far as temperatures go.  A cold front crossed the state the night of December 3rd, and an arctic air mass followed. Low temperatures fell into the 20s in the Triangle the morning of the 4th, and with that cold air in place at the surface, when moisture arrived, wintry precipitation began to fall.

You can see by the map created by Jonathan Blaes and Phillip Badgett at Raleigh’s National Weather Service office that northern Wake County recieved up to an inch of freezing rain.  Additionally, another one to two inches of snow fell.  It was definitely a storm for the history books, especially since the Triangle ususally doesn’t see winter storms like that until late winter and early spring.

Thankfully, this week’s arctic blast will have dry air behind it.  While we’ll need warm coats, gloves and scarves, snow boots are not going to be necessary.