Wet weather to continue – Patchy fog possible Monday morning, Feb. 10. Forecast upgraded to flood watch starting Monday afternoon and lasting through Tuesday evening.
“Beginning Monday afternoon, a stalled frontal boundary will bring moderate to heavy rainfall to the southwest North Carolina mountains, parts of northeast Georgia, and far western Upstate South Carolina,” states National Oceanic and Atmospheric Administration’s National Weather Service. *Rainfall amounts of 2-3 inches (locally higher in some spots) Monday night and Tuesday are expected, which may lead to new flooding and worsen conditions in areas that have not yet recovered from flooding last week. Saturated ground and continued high river and stream levels may lead to flooding developing quickly. Rapid rises above banks on streams and creeks may occur, along with the threat of flooded roadways. Flooding is also likely to re-develop on larger rivers. The heavy rainfall will also greatly increase the risk of landslides.”
The full week forecast for Toccoa/Stephens County also shows rain continuing past the Tuesday evening closure of the flood watch, with 70 percent chance of showers through Friday morning. Friday is predicted to be dry and sunny, with high temperatures in the mid 50s.
The snowfall Saturday compounded the soil saturation and rising rivers and streams cause by the several inches of rainfall Thursday. As of 9 p.m. tonight, Feb. 9, the official snowfall over the weekend in Toccoa was 4 inches, with up to 6 inches recorded in the western edges of the county, and National Weather Service snowfall analysis for the past 72 hours showing 3 inches in the southern part of the county. However, multiple measurements taken by residents throughout the county showed slightly higher accumulations. In very general terms, eight to 12 inches of snowfall is equivalent of one inch of rainfall, depending on the density of the snowfall.
Monday: A chance of rain between 10 am and 5 pm, then showers likely after 5 pm. Patchy fog between 8 am and 9 am. Otherwise, cloudy, with a high near 54. Light and variable wind. Chance of precipitation is 60 percent. New precipitation amounts between a tenth and quarter of an inch possible.
Monday Night: Showers. Patchy fog before 2 am. Low around 50. North northeast wind around 5 mph becoming light and variable in the evening. Chance of precipitation is 90%. New precipitation amounts between 1 and 2 inches possible.
Tuesday: Showers. High near 67. West southwest wind 3 to 7 mph. Chance of precipitation is 90%. New precipitation amounts between a half and three quarters of an inch possible.
Tuesday Night: Showers likely, mainly before 10 pm. Mostly cloudy, with a low around 49. West wind around 5 mph becoming calm in the evening. Chance of precipitation is 60 percent.
Wednesday: Showers likely, mainly after 10 am. Cloudy, with a high near 62. Chance of precipitation is 70 percent.
Wednesday Night: Showers. Low around 54. Chance of precipitation is 90 percent.
Thursday: Showers likely, mainly before noon. Cloudy, with a high near 63. Chance of precipitation is 70%.
Thursday Night: A 30 percent chance of showers before 10pm. Mostly cloudy, with a low around 39.
Friday: Sunny, with a high near 55
Friday Night: Mostly clear, with a low around 33.
Saturday: Sunny, with a high near 50.
Lake Hartwell, at 7 a.m. this morning, Sunday, Feb. 9, was at 662.58 Feet MSL(feet above Mean Sea Level), which is 2.58 feet above full pool of 660.00 and 2.42 feet below flood pool of 665.00 feet. The lake was at 659.31 feet on Feb. 3, and rose 3.27 feet from the rain and snow accumulations of the past week.
The highest recorded lake level since 2015 was a measurement of 664.83 on Jan. 5, 2016. A review of lake level records past 2015 show that the last time the lake rose above the 665.00 feet flood pool was in Jan. 1, 2014, when more than 8 inches of rain fell in the region in the previous month. Although the January 2014 rains marked the second time in six months the lake rose above its banks, during neither instance was the rise high enough to impact roads or close recreation areas. The Corp did, however, open floodgates after the July flooding to lower water level.
The U.S. Army Corps of Engineers, which manages Lake Hartwell, has identified 660.00 feet above Mean Seal Level as “full pool” for the lake, which claims 962 miles of shoreline and 56,000 acres under water at full pool. The Corps has identified a five-foot “buffer zone” that acts as flood storage, resulting in a 665.00 flood pool – a level at which the Corps officially considers the lake “flooded.” The Corp can mitigate levels that rise above the flood pool by use of extra power generation and water releases.
A majority of Hartwell’s recreation impacts don’t occur until the lake is around 663-664 feet, Corps spokeswoman Tracy Robillard told reporters in 2014. However, a Corps of Engineers press release in January 2014 stated, “With lakes already high and the ground saturated from recent rainfall, an inch of rain in the basin could add a foot to the water level of the lakes, which would put the water managers into “flood-fighting mode.”
Atlanta, Ga. averages about 45 inches of precipitation per year; multiplying this by the 2.293 billion gallons shown in the table as the number of gallons in 1 inch reveals that some 103.2 billion gallons of water fall on Atlanta in an average year. In a city the size of Atlanta, the per capita water use is about 110 gallons per day or 40,150 gallons per year. Thus, the water from a year's precipitation, if it could be collected and stored without any loss, would supply the needs of about 2,574,000 people.
(SOURCE – USGS.GOV)