Atlanta Water Shortage

According to the Lawrenceville Weather Blog, we’ve got a chance at seeing some snow (or sleet, or freezing rain, or ice) next week.

Accuweather almost agrees, saying that we’ll get “Rain, which can freeze on surfaces late”.  Whichever forecast you prefer, it seems like to be near freezing with some precipitation, which means it could get interesting.

Accuweather is calling for around 4/10″.  Even if it’s frozen, it will melt pretty quickly and give us a tiny bit of relief.  The lake has been holding pretty steady lately (we’re at the exact same level as last Sunday - 1051.28′), but this is the time of year when we really need it to start rising.

Dr. Jeff Masters, co-founder of the Weather Underground, has written an excellent article about the the state of the drought, the causes of the drought, and a look ahead.

Some highlights:

• We had a very dry year in Atlanta, but Birmingham and Huntsville were even further below normal.
• Droughts tend to run in two-year cycles every 25 years, with longer ones sometimes mixed in.  2006 saw normal rainfall in Atlanta, which points to 2008 being quite dry.
• Global warming likely has nothing to do with the current drought.  The globe has warmed by 1° F in the past 100 years, but the southeastern U.S. has cooled by 0.1° F over the same period.  No one quite knows why.

All in all, it’s a great read.  Check it out.

For the first two months of running this blog (October 15 - December 15), Lake Lanier got lower every single day.  December 15th was the first day that we saw a small rise (1/8 inch), after which it fell some more.

However, with the rain over the last few days (a total of 2.44 inches recorded at Lanier), the lake has risen by 5.28 inches in the last three days.  Over half of that gain was yesterday, when the lake rose by 2.76 inches.

The other good news from this is that any rain we receive will continue to help us for a few days, because less water will need to be released from the lake as a result.  We covered that effect more in-depth a few months ago.  With no rain today, the lake is still up by about an inch (though the daily release is scheduled for later this evening).

The drought obviously isn’t over (the lake is still 20 feet low), but how good is this news?  Is it exciting that the lake has risen this much in the past few days?  Or is it just a blip on the radar and we’re still in deep, deep trouble?  Leave your thoughts in the comments.

The driest year on record for the city of Atlanta was in 1931, with a total of 29.14 inches.  With the recent rain, Atlanta is now at a total of 29.27 inches for the year.

Even better, the short-term forecast is looking pretty good, with north Georgia possibly getting 3-4 inches of rain in the next five days.  That certainly won’t solve our problems, but every little bit helps.

The Lawrenceville Weather Blog has the full details.

So far, all signs point to “yes”.  This article on watercrunch sums it up pretty well.

The primary factor seems to be La Niña, the current weather pattern that is likely to bring us warm, dry weather throughout the winter and into the spring, which we’ve discussed before.

The key seems to be in the next 3-4 months.  If we don’t get much rain during that span, things will almost certainly be worse heading into next summer/fall.

For the first time since this this blog was started nearly two months ago, the level of Lake Lanier went up due to the rain yesterday.

Granted, it only went up by 0.01 feet (about 1/10 of an inch), and it’s already dropping today, but it was certainly nice to see.

As was the case during the last bit of rain we got, Lake Lanier dropped even further yesterday in spite of the rain. In fact, since this blog started (October 16), the lake has dropped every single day.

However, there is a bit of somewhat good news. The lake only dropped 0.03 feet yesterday, which was the lowest single-day drop in over a month. In addition, we should see less water released from the dam over the next few days, as the Chattahoochee will be getting extra water from the rivers and streams that feed into it because of the rain (explained a bit further in this post). In fact, the lake is actually up by about 0.04 feet for the day, though that gain will probably be erased during the evening water release at the dam.

The other good thing that could come out of the rain is that the ground is now holding more water. The problem we’ve been having is that each time it rains, the ground just soaks it up because it had been so long since the previous rain. If we can get some more rain the next few days, it would probably be more beneficial because the ground won’t be quite as dry. However, the rain that was forecast for this weekend seems to have evaporated and nothing is expected until late next week. At the point, the ground will be getting pretty thirsty again.

As with every bit of rain we’ve seen over the last few months, the rain we got on Wednesday night and Thursday morning had no direct benefit for Lanier.

Lake Lanier (measured in Buford) got a total of 0.43 inches of rain.  However, during Wednesday and Thursday the lake dropped by another 3.24 inches.

We’ve explained before that rain on one day can be of some benefit for a few days down the road.  However, I don’t expect that .43 inches will help much at all.

Accuweather’s forecast still shows some rain possibly coming our way Saturday night, Sunday and Sunday night, with an expected total of around 0.79 inches, with another storm maybe arriving around the first of December.

The AJC has just put a countdown on their drought page that shows exactly how much time is left for Lake Lanier.  As of right now, there are about 90 days and 1 hour left.  The problem with this countdown, as with most of them, is that they don’t explain where that number comes from — wasn’t it just “79 days left” about a week ago?

The good news is that some of the rain forecast for our area seems very likely to happen.  The specifics from Accuweather:

• Tonight - 0.65 inches
• Thanksgiving - 0.20 inches
• Saturday night - 0.99 inches
• Sunday night - 0.50 inches
• Monday night - 0.36 inches
• Tuesday - 0.25 inches
• Tuesday night - 0.50 inches

Now, we all know how often weather forecasts are wrong, but that is certainly encouraging.  That’s nearly 3.5 inches of rain forecast over the next week — far more than the 2.26 inches we’ve seen since October 1st.  We’ll be sure to update the official rainfall amounts on our Lanier Rainfall page, as well as show exactly what that rain has done for the lake level.

Given how dry the ground is, even 3.5 inches of rain won’t do much.  However, it’s important to realize that rain today might help the lake for a few days down the line, as the Corps can probably reduce the flow because of extra water from the smaller rivers that feed into the Chattahoochee (we explained that a bit in this post).

Even if it doesn’t do much to help, every little bit is good.

According to the Lawrenceville Weather Blog, our short-term outlook is pretty good. The summary of their article:

• Pleasant weather through Wednesday.
• 1/2 inch of rain late Thursday or Friday morning.
• Rain again on Tuesday, 11/27 until Thursday, 11/29.
• Another storm the first weekend in December.

They point out that we’ll still be well below our normal for the month (and way below our yearly total), but it’s a good start.

Their forecast seems to jive pretty well with Weather.com 10-day forecast. However, the Accuweather.com 15-day forecast is a bit different though it still shows rain on a handful of days. In any case, this looks to be pretty good news.