The
snow that everyone graved finally came to the Midlands. The same storm system that affected
Birmingham and Atlanta also affected Columbia, SC. Rain and sleet began to fall before noon on
Tuesday, but it wasn’t enough to measure and didn’t cause any problems. The lower atmosphere was quite dry so that it
would take hours of light precipitation to moisten the atmosphere enough to
allow for any significant precipitation.
Finally
a band of rain/freezing rain moved across the southern half of the Midlands
just before dark. This was followed by
snow in the northern part of the Midlands.
It eventually reached Columbia in the form of freezing rain. At WLTX we pick up an ice accumulation of
1/10 of an inch before the precipitation changed over to snow. The southern third of the Midlands saw ice
accumulations of a ¼ to ½ inch.
The
air was chilled by the rain/sleet/snow mix and temperatures fell below freezing
over all of the Midlands shortly after sunset.
The precipitation changed to snow which fell mainly from 7:30 p.m. to
about 2 a.m. across the Midlands. Snow
ended from west to east and the amounts didn’t vary a great deal across the
Midlands.
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| A map of the midlands of South Carolina showing total snow depth as of Wednesday morning January 29, 2014. This is from preliminary data. Click on the image for a larger view. Image Credit: NOAA/NWS/CAE. |
Amounts
were generally 2 to 3 inches across much of the area. It was a wet snow which made for great
snowmen and snowball fights. Here is a
view of the region from the satellite the next day:
 |
| A visible satellite view from Wednesday January 29, 2014. The solid white area at the bottom of the picture are clouds for the most part. Elsewhere skies are clear and the white areas are snow on the ground. Click on the image for a larger view. Image Credit: NASA. |
Skies
cleared late Wednesday and calm conditions developed overnight. In addition, the snow cover allowed for good
radiational cooling to occur. This
allowed temperatures to drop to very cold readings by Thursday morning. The temperature at the National Weather
Service Forecast Office in Columbia was 13° F for the low. The lowest temperature occurred at Cedar
Creek (northern Richland County) with 6° F.
We
are fortunate to have a mesoscale network of sensors around Richland County. This network showed how temperatures can vary
on just a county scale. Below are the
low temperatures for Thursday morning:
 |
| Low temperatures around Richland County, SC, for Thursday morning on January 30, 2014. Click on the image for a larger view. Image Credit: Ken Aucoin/ RC Winds. |
How well was this
forecast?
Daniel
Bonds and I spent a couple of hours Sunday afternoon evaluating the many
different models. The GFS (American)
model did the best in capturing the ice accumulation and snow accumulation. It wasn’t perfect, but it did the best job.
Our
own in-house model (RPM) did the worst, but it was greatly influenced by the
American WRF model. Also, the European
model was too cold which led to high snowfall totals and no ice. The European model was forecasting snowfall
of about 7 inches while the WRF was forecasting about 15 inches for
Columbia. These were unrealistic in my
view given the dynamics of the atmosphere.
I
suspect that this tainted some of the local forecasts of snow. I frequently saw forecasts of 3 to 5 and 5 to
7 inches of snow. Our forecast for 2 to
4 inches of snow hit the mark for the central Midlands. However, our view of closer to 4 inches for
the northern Midlands was too high. The
forecast of 1 to 2 inches of snow for the southern Midlands worked, but was a
little low in places. Our forecast for
ice accumulation for the southern Midlands was spot on, but a little high for
the central Midlands.
You
can see the forecasts from the GFS model in the previous two posts. I did not make a map of forecast snow, but
talked in general terms. When you have a
storm producing a mix like this one, timing is everything. Freezing rain and sleet tend to compact the
snow leading to smaller snow depths. An
all snow event would likely have produced amounts in the 3 to 4 inch range.
We
weathered the storm much better than cities to our west. The situation in Atlanta has received the
most media attention. I would direct you to two posts which cover it quite
well. The first post is from the president of the American Meteorological Society (soon to be
past-president) and teaches at the University of Georgia. The second post is from Bryan Norcross at the Weather Channel.
It
will be warming into February and January will be a fading memory. However, looking at the overall pattern for
North America, the weather pattern is changing to something we have not seen
since November. Fasten your seatbelt,
because it looks like it is going to be a wild ride. Stay tuned!
