NOAA's National Centers for Environmental Information
During the month of February, cold air in the wake of several reinforcing Arctic air masses dominated much of the U.S., creating temperatures that were much–below average in the Deep South. These cold temperatures, combined with the active weather pattern in the southern and eastern U.S., produced historic snowfall events — see the national temperature and precipitation state of the climate report. These events, contributed to above-normal snow cover extents across the contiguous U.S. and North America for the month. Snow cover extent during February 2010 ranked as third largest February since 1967 for North America and the United States. The North American monthly area snow extent was 18.58 million square km (7.17 million square miles), 1.5 million square km (579,000 square miles) above the long–term average. Snow cover in the U.S. extended to 4.6 million square km (1.8 million square miles), 1.5 million square km (579,000 square miles) above the long–term average. At the beginning of the month, snow was present for approximately 69 percent of the contiguous United States, including a wide swath of area that stretched across some of the southern tier states. Winter storms during the month added to existing snow depth in the Mid-Atlantic states, but snow cover had decreased to 47 percent by the end of the month mostly due to the melting of the thin layer of snow pack.
Arctic sea ice extent during the month of February was below normal. With an unusually strong high pressure over the area, most of the Arctic Ocean experienced warm temperatures during the month. This coincided with another strong negative Arctic Oscillation phase, which has been persistent throughout much of the 2009-2010 winter season. The Pacific side of the Bearing Sea had above–average ice extent. The Arctic ice extent averaged 14.58 million square km (5.63 million square miles), 1.06 million square km (409,000 square miles) below the 1979–2000 average for February. Arctic sea ice during February 2010 was 220,000 square km (85,000 square miles) greater than the record low for the month, which occurred in 2005. During the month, the sea ice extent grew at an average rate of 25,700 square km (9,900 square miles) per day, with ice growing faster at the beginning of the month compared to the end. Please see the Arctic Sea ice analysis by the National Snow and Ice Data Center for additional information.
A series of major snowstorms plagued the Atlantic states throughout the month, most notably a back-to-back punch of snowstorms on February 4-7 and February 9-11 that broke monthly and seasonal records in many of the major cities across the Atlantic seaboard. These storms ranked as Category Three and Two (*upgraded to three) storms on the Northeast Snow Impacts Scale (NESIS), respectively. However, if combined and treated as one storm, the resulting combined total would become only the third Category Five storm (the most extreme category) of the NESIS record.
Monthly Snowfall Records at Select Locations
| Location | Old February Record/Year | New February Record |
|---|---|---|
| Baltimore, MD | 40.5 Inches 2003 | 49.7 Inches |
| Washington, DC (Dulles) | 34.9 Inches 2003 | 46.1 Inches |
| Beckley, WV | 30.8 Inches 1964 | 45.0 Inches |
| Charleston, WV | 21.8 Inches 1964 | 25.6 Inches |
| Elkins, WV | 32.0 Inches 1986 | 43.8 Inches |
| Central Park, NY | 30.5 Inches 1896 | 36.9 Inches* |
| LaGuardia Arpt, NY | 25.6 Inches 1993 | 29.1 Inches |
| Pittsburgh, PA | 25.3 Inches 2003 | 48.7 Inches* |
On February 4th-6th a storm that originated in the southwest U.S. traversed eastward pumping in moisture from the Gulf of Mexico and the Atlantic. Dubbed "Snowmageddon", this massive winter storm caused government offices, schools, and airports to close. Some locations in Maryland, Pennsylvania, Virginia, and West Virginia recorded more than 30 inches of snow. In Washington DC (National), the two-day total of 17.8 inches ranked as the fourth highest total storm amount in history. On January 27th-29th 1922, what is known as the "Knickerbocker storm" produced 28 inches in DC, the most ever. In Philadelphia, the 28.5 inches ranked as the second highest amount, behind the 30.7 inches on January 7th-8th, 1996. The 24.8 inches that fell in Baltimore was its third highest storm total amount.
The cold and snowy weather pattern remained entrenched along the east coast as another ferocious blizzard created havoc during February 9th-11th on the areas that were still digging out from the historic blizzard of February 5th-6th. Although not as moist as the previous storm, this blizzard rapidly intensified forming a "bomb". While the pressure dropped, the winds increased causing blowing snow and blizzard like conditions. This powerful nor'easter produced as much as 14 inches in the D.C. area, 20 inches in Baltimore, 17 inches in New Jersey, more than 27 inches in Pennsylvania, and as much as 24 inches in northern Maryland. As a result of these two storms, several locations broke seasonal snowfall records, some of which were more than a century old.
Seasonal Snowfall Records at Select Locations
| Location | Old Record/Season | Season-to-Date* |
|---|---|---|
| Baltimore, MD | 62.5 Inches 1995-96 | 80.4 Inches |
| Washington, DC (Dulles) | 61.9 Inches 1995-96 | 73.2 Inches |
| Washington, DC (National) | 54.4 Inches 1898-1899 | 56.0 Inches |
| Philadelphia, PA | 65.5 Inches 1995-96 | 78.7 Inches |
| Wilmington, DE | 55.9 Inches 1995-96 | 72.7 Inches |
| Atlantic City, NJ | 46.9 Inches 1966-67 | 58.1 Inches |
This season's snow was not confined to just those in the East Coast as a rare storm brought heavy snow to the deep south. On February 11th-13th, as much as six inches of snow fell in Louisiana, Alabama, Mississippi and even the northwest Panhandle of Florida. A new daily snow record fell in Dallas, TX. The local weather forecast office out of Dallas/Forth Worth reported that 11.2 inches bested the old record of 7.8 inches set in Jan 15th, 1964 and Jan 14th, 1917. It was also reported that 170,000 electric customers were without power at the peak of the storm. On February 13th 49 of the 50 United States had snow on the ground, with Hawaii being the exception. Not even the 13,800 foot volcano, Mauna Kea, the most likely place to find snow in Hawaii, had snow.
The winter of 2009/2010 continued during the last weekend of February as a powerful, slow moving low pressure system off the Atlantic Coast, slammed the Northeast with a mixture of rain, ice, snow and high winds causing beach erosion, and inland flooding. While a blocking pattern prevented the previous February storms from tracking deep into the New England area, this latest storm dumped more than 2 feet onto eastern New York state, western Massachusetts, and southern Vermont. Flooding rains were a concern over areas in Rhode Island, Connecticut, Southern New Hampshire, and Maine where as much as 8 inches of rain fell during the five day event.