Thursday, April 12, 2012

The Great April 15 Snowstorm

Charlotte's near-freezing temperatures Thursday morning seemed like quite a shock after weeks of 70s and 80s in March and early April, but it could have been worse.

In fact, it has been worse.

Mecklenburg County commissioner Bill James, who has a real interest and a good understanding of all things meteorological, passed along an item he found in a history book of Mecklenburg County. It was an excerpt about a big snowstorm on April 15, 1849.

I found several other accounts of the same storm, and interestingly, it appears to have developed in a year much like 2012. Temperatures had been unseasonably mild in March and April, but very cold air spilled into the South in the second week of April. It's not clear exactly what happened, but based on the results, we can guess.

There are published accounts of a big snowstorm that struck April 14 and 15 in parts of Louisiana, Florida, Georgia and the Carolinas. So we can assume that low pressure formed in the Gulf of Mexico and tracked across the Deep South, into the cold air that had pushed southward.

Mid-April snow in Florida? Just imagine that!

But the Carolinas took a hit.

The Mecklenburg County account, in the book that Bill James found, describes it this way:

"Everything in the way of vegetables was well advanced in the spring of 1849. The farmers were ready to give corn its first plowing when the snow came. It fell very gently, no crust on top.

"It was so piled up in the apple blossoms that they looked like snow balls. All vegetation was killed, no fruit that was in bloom escape being killed. The great crop of Mecklenburg blackberries alone escaped, of all our fruits.

"It was not until mid-summer that the trees made a respectable shade, or the cattle could make a tolerable living in the range at large."

That account says 5 inches of snow fell.

Meteorologist Don Sutherland, who has published a number of books and blogs, notes an account of the storm in the Camden (S.C.) Journal:

"It commenced with a slight fall early in the morning (April 15) and continued to increase in quantity until 2 or 3 o'clock in the afternoon, when it fell in large flakes, as in mid-winter ... The housetops were covered with snow, which had not melted on Monday morning (April 16). A mid-winter scene in early spring is a sight that we do not remember to have seen at any former period."

The S.C. Department of Natural Resources says 6 inches of snow was measured in that storm in Columbia.

So it appears the April 15, 1849, event was a storm that hit South Carolina and the southern edge of North Carolina.

The National Weather Service's records for Charlotte go back only to the winter of 1878-79. Since then, the record snow in April was 3.5 inches, on April 9, 1880.

Thursday, April 5, 2012

Cool weather? We knew it was coming

Everyone has been saying it for the last few weeks, as we experienced day after day after day of temperatures far above seasonal averages.

"It'll cool down eventually. We'll get a cold snap in April."

And here it comes, although it's not clear exactly how cold it will get.

Canadian high pressure will take control of Charlotte-area weather Friday, and we'll notice the difference. Temperatures will struggle to get out of the 50s, unless enough sunshine breaks through the overcast Friday afternoon to allow a recovery into the low 60s.

Then we'll have morning lows in the upper 30s to near 40 degrees Saturday, and the low to mid 40s Easter Sunday. Afternoon temperatures won't be bad, with highs around 70 Saturday and in the mid 70s Sunday.

But there won't be a return to 80 degrees next week. Instead, another cold front is forecast to push across the area late Monday or Tuesday, holding afternoon highs to the 60s again for Tuesday and Wednesday.

National Weather Service meteorologists are closely watching for the possibility of frost on those chilly mornings. The unseasonably warm weather in March and early April caused strawberries to ripen early and fruit trees to blossom several weeks before they normally do. A freeze could be devastating to farmers.

The good news? At this point, it appears as if morning temperatures won't quite dip to freezing levels in areas where trees have blossomed.

Forecasters have predicted April will be warmer than average, overall, and that could happen, despite next week's cool down. Accu-Weather forecasts call for a return to the low 80s by late next weekend or early in the week of April 16.

Monday, April 2, 2012

March 2012 ... one for the record book

We've just completed the second-warmest March in Charlotte weather history, but that was nothing, compared to what happened over much of the continental United States during the month.

Dozens of cities, from Maine to Wyoming, broke records for the warmest March ever.

Some cities set daily high temperature records for a week in a row. In one Michigan city, a daily high temperature record was broken by 42 degrees -- and even the morning low was warmer than the previous record high for the date.

More of the same is expected in April, although the start of the month might be a bit cooler than we've seen in recent weeks.

In Charlotte, the average temperature -- calculated by averaging out the daily highs and lows at Charlotte/Douglas International Airport -- was 61.3 degrees. The only March that was warmer was in 1945, when the average was 61.6.

We had 10 days with highs of 80 degrees or warmer, which tied a record for the month.

But several Carolinas cities had the warmest March on record. And it was the same over much of the nation, except for the West Coast, the Southwest, Alaska and Hawaii.

Tampa set a record for the warmest March. So did Riverton, Wyo. So did Portland, Maine. For that matter, so did Winnipeg, in the Canadian prairie province of Manitoba. In fact, the average temperature in March for Winnipeg was 20 degrees warmer than usual.

Perhaps the most amazing event came March 21, when it climbed to 81 degrees in Marquette, Mich., up along Lake Superior on the U.S.-Canada border. The former record high for March 21 was 49 degrees. 49! And the high for the date was 81!

NOAA's forecast for April is a continuation of above-average temperatures in most of the East, although meteorologists also expect the month to be dry. March, while very warm, produced average rainfall totals in much of the Carolinas. The next week or two is expected to be cooler than average in the Carolinas, with a warm-up afterward.

Incidentally, before you get started on the Global Warming Chorus, be aware that March was very chilly on the other side of the globe. It was cold and wet over much of the United Kingdom and Europe.