Local Watches / Warnings

Sunday, April 27, 2008

Drought Update- Southeast April '08


Clarification:

In the Below [Text Extract] Report from the National Weather Service, Southeast River Forecast Center, the issue date is Wrong. The Issued date displayed is- April 23, 2007; The Actual Date should be- April 23, 2008. The PDF Report from which this text version was created, according to the PDF Document Properties, was created on Tuesday, April 22, 2008, at 2:44:12 PM. The PDF Document can be found here- Southeast U.S. Water Resources – Where Do We Stand?

Note:

When I report on the Southeast Drought, My main area of concern is the Atlanta,GA., Lake Lanier Area southward. From the below report and other information accessed on the Web, the Forecast does Not look good. I looked at the 30 to 90 day outlook for temperature and rain in the Southeast, also the 2008 Hurricane Season forecast. From the information provided, again, the situation does Not look good.

Lake Lanier at this time unlike last year[2007] is well below historic mean for 04/15/08 with a level of 1057.4. In October of 2007 the lake level was at 1055.91. The Late Fall, Winter, and Early Spring months are the time of Water Regeneration in the Southeast. As you can see from the levels and dates above, the lake has only risen about 1.5 Feet over this period of regeneration. The current level for Sunday, April 27, 2008, is 1057.54 which is a gain of little more than a tenth of an inch.

Doom&Gloom:

As we know drought in the U.S.A. as a whole has become more frequent over the past years. The Southeast along with areas in the Midwest and west have endured record drought. For the Atlanta,GA. area, what we see as the only remedy at this time is a Land falling Hurricane or Tropical system which lingers and dumps copious amounts of rain. The down side of this is the destruction due to wind and the possibility of Major Flooding. If some type of tropical system does not occur in the southeast this year, we feel the Atlanta,GA. area will be high and dry. We are basing this on past years and the current forecast for 2008, which tell us chances of appreciable rain are equal or normal. Normal amounts of Precipitation are NOT going to be able too keep the water flowing. The rate at which it is being consumed, is greater than which it is being replenished.

Side Note:

As you may know if you live in the Southeast, many towns and communities Ran out of Water last year. And YES, Water was Rationed for people in these areas. It is only getting worse as the days go by. I would suggest those of you in the Southeast begin, if you haven't yet, stock up on water.

The drought really didn't relinquish it's hold during the winter months. People tend to forget about the situation once trees loose leaves and grass goes dormant. This Spring I have had to pull up, and cut down many plants and shrubs that didn't come back, due to lack of water over the winter months. They were all alive in late summer and early fall of '07. When it was time for the New growth this spring, they were Dead. One tree was a sapling planted 5 years ago and was well established along with what I will call it's sister, One survived and the other died. Summer isn't here yet and the grass is already brown and crunchy, instead of the Lush Green it should be for this early time of year.

Summary:

This is just a heads up for those that are following the Drought Situation in the Southeast. From what has occurred in the past, to what is forecast for this year, and what I think is going to happen. This is in No Way and accurate forecast, as even the most educated meteorologist will tell you, anything can happen. At this time however, It doesn't look good! And remember, Water is used to Generate electricity!

For Previous Drought Reports Click Here. The previous reports also have graphs and Images of area Lakes.


National Weather Service
Southeast River Forecast Center

Southeast U.S. Water Resources – Where Do We Stand?
Wylie Quillian – Senior Hydrologist
John Feldt – Hydrologist-in-Charge

Issued: April 23, 2007

Summary: Normal rainfall from late winter into early spring helped improve water resources across most of the Southeast U.S. Most notable improvement has been to water resources that typically respond quickly to increased rainfall. This includes smaller tributaries, smaller lakes and ponds, and certain reservoirs.
A number of major reservoirs have seen significant recharge over the past few months, in some cases rising from well below normal to near normal levels.
However, a few locations remain lagging, especially Lake Lanier in Georgia, Lake Okeechobee in Florida, and much of the Savannah River basin.
While some improvement has been noted over the winter and early spring, it is important to note that the entire area remains at risk for continued drought as we move into summer.



As we have been noting for quite some time, there is a seasonal period of peak recharge for much of the Southeast U.S. (with the exception of Florida) that extends through the winter and early spring months.
As we head towards May, most locations have now seen a “green up” of foliage which will reduce runoff due to increased evapotranspiration. In addition, rainfall becomes more convective and scattered in coverage. As temperatures warm, evaporation will increase.

So, have water resources improved during this recharge period? This study will look at three key factors: rainfall, reservoir levels, and stream flow.

Rainfall: Past 90 Days



In this graph, areas of yellow indicate below- normal rainfall, while green and blue areas indicate above-normal rainfall (as of early April).
Rainfall over the winter was somewhat below- normal (75 to 90 percent of normal) over most of the region. An exception was eastern North and South Carolina, Southern Georgia, and much of Florida, where rainfall was above normal (100 to 150 percent of normal).
While still below normal, it was an improvement over last summer and fall. Accumulations generally increased over this 90-day period due to increased activity in February, March, and early April.

Stream Flow
Stream flow measurements are made by the U.S. Geological Survey (USGS).



The above chart represents a 7-day average stream flow. Note that much of the Southeast U.S. is reporting stream flows near normal for this time of year. Exceptions are river basins over far western North and South Carolina, the Upper Chattahoochee, and much of the Savannah River basins.
Note: some of these flows are low due to reduced outflows from reservoirs as much as from natural conditions.


Reservoirs
A review of larger reservoirs across the Southeast U.S. indicates an improvement in pool levels over the winter.



Areas with the least improvement include South Carolina, Northeast Georgia, and much of Florida.

Reservoir            Date        Pool     Target Pool     Comment

John H. Kerr Lake   04/14/08     305.2       301.6       Target varies by date

Jordan Lake         04/14/08     219.7       216         Target is bottom of flood control pool

Falls Lake          04/14/08     252.4       251.5       Target is bottom of flood control pool

High Rock Lake      04/15/08     653.8       652         Target is historic mean pool elevation for April

Lake Marion         04/15/08      74.7        75.5       Target is normal for 04/20

Lake Hartwell       04/15/08     652         660         Target is rule curve per weekly declaration

Lake Thurmond       04/15/08     322.2       330         Target is rule curve per weekly declaration

Lake Lanier         04/15/08    1057.4      1070         Target is well below historic mean for 04/15

Lake Seminole       04/15/08      77.5        77         Target is normal target pool.

Lake Allatoona      04/15/08                 840         Target is summer top of conservation pool

Lake Martin         04/15/08     489.2       490         Target is normal summer pool

Lewis Smith Lake    04/15/08     509.5       510         Target is normal summer pool

Lake Okeechobee     04/15/08      10.5        14         Target is historic mean for mid April

Drought Monitor
The following graphic shows the change in the U.S. Drought Monitor for a 16-week period from mid December into early April. Note that almost all of the Southeast U.S. has seen significant improvement in drought conditions. Fairly large areas have seen a 2- class improvement with isolated spots as much as 5- classes.



A Word of Caution Looking Ahead



It is important to remember last year around this time. It is to be expected that water resources will improve during the peak recharge period. Last year much of the area was in extensive drought heading into winter. By early spring there was a significant improvement observed. However, once we exited this recharge period, drought conditions again took hold and the drought significantly intensified over the summer.



No comments:

Post a Comment

Welcome to my little neck of the woods in West Central Georgia. What's on your mind ? *Spam will be deleted.

Related Posts Plugin for WordPress, Blogger...