Spring comes early …

but it won’t stay.

If you have been watching the news, or if you live in the East and have gone outside, you’re already aware of how warm this December has been. My brother visited us Sunday and pointed out that our daffodils are starting to grow, at the time that most gardeners recommend planting bulbs.

early daffodils

It’s no surprise. Our nightly low temperatures have been higher than the normal highs for days this month.

My brother said that forsythias, which are also spring bloomers, are blooming now in Chattanooga, where he lives. I heard a radio story last week that had reports from a lot of places around the country of blooming plants and even new baby birds.

Unfortunately, the lows here are expected to be below freezing later this week. Neither the early plant growth nor the early birds are likely to survive through the winter, and winter will come, even if it’s late.

I have not seen much about a connection between this warm weather and global warming. Most meteorologists or weather people have talked about a strong El Niño. That usually is associated with wetter weather and cooler than normal winter temperatures here in Georgia. We are getting wet weather, but not cooler temperatures.

Climatologists almost always warn against associating a specific weather event with global warming (or climate change as it has become known, mainly because of conservative opposition to science). However, there are certain mathematical and statistical properties that measurements of many physical quantities follow. Such measurements include things like the height of 20-year-old males or the weight of full-term babies at one year. They also apply to things like measurements of high temperatures on a given day of the year at a given location. Such measurements almost always have what is called a normal distribution. In a normal distribution, measurements tend to group around the average, and have fewer measurements either higher or lower than average. A normal distribution will also have the same number of measurements below and above the average.

Accurate, reliable temperature measurements have been made for a limited time in most locations, so the number of measurements on any given day of the year will be fairly small, probably under 200. As a result, new record lows and highs will be recorded occasionally, although probably decreasing over time as more and more data accumulate. Since temperatures almost certainly follow a normal distribution, there should be a roughly equal number of new record lows and highs over a reasonably long period. If you start seeing more record highs than record lows, it probably means that something is changing. That’s what we have been seeing that in recent years.

Global warming won’t mean that we don’t have cold winters, and it won’t mean that we don’t have new record low temperatures. But it will mean that we will see events like the warm December of 2015 more and more often in the future.

Windy night

Tuesday night a line of strong storms was moving into Georgia, and it looked like we would get a lot of it here. Around 7 pm it got windy.

These are the trees behind our house. They are pretty tall, and they were whipping around dramatically.

This is what my phone’s weather app showed for the radar at 7:00.

storm7pmThe pushpin is right at our house on the mountain. The blue boxes are storm warnings. Here is what it looked like at 8:30 when the line was almost on us.

storm830pmThe heaviest rain has already split to pass around us. By 8:55 we were getting fairly heavy rain, but not the heaviest.

storm855pmIt was all over here by 10:15, although it looked like we would get at least some additional light rain. We didn’t.

storm1015pm

We got about 0.96 inches of rain, enough to help, but not as much as we needed. Others got significantly more.

 

 

 

 

In the donut hole

We have been in a very dry period up here on the mountain for the last few weeks. We’ve had one rain event of nearly a half an inch, and a couple of drizzles that gave us about 0.02 inches each.

It’s not that there has been no rain anywhere in northwest Georgia, it just seems that it keeps missing us. On Thursday when I met the well driller up at the new house, there were dark clouds and thunder. The well man wasn’t sure he wanted to erect the drill rig because of the lightning. Here’s the sequence on my phone’s weather radar app as I watched the rain fall all around us.

june25radar4_20

june25_4_30

june25_4_40

june25_5_10

 

We got just enough actual precipitation to get the new garage slab wet, but not enough to wet the dust in the yard.

Friday we had a severe thunderstorm warning. It looked bad enough that I wasn’t sure I wanted Leah to drive down the mountain on an errand. I shouldn’t have worried. Here’s that sequence.

june26_3_55

june26_4_00

june26_4_25It looks like we were on the edge of the heaviest rain, but the total as of 7:45 pm was 0.02 inches.

I’m glad there has been rain around us. I assume that rain around us refills the aquifer we rely on, although I have no actual knowledge of hydrology. That’s good, since it means our well probably won’t run dry, but it doesn’t help all the plants that need water.

 

Evening clouds

As usual, we saw some nice cloud formations as we left the grocery store Friday night. This was from the parking lot.

crepuscular_wmlotThe crepuscular rays weren’t particularly noticeable as I looked at the clouds, but they showed up well in the photo. I like the way the cloud in the middle left is half illuminated and half in shadow.

When we drove home, there were more nice clouds. We managed to snap a few shots and got this one.

crepuscular_huffaker2Again, the crepuscular rays were not really noticeable as we drove, but they showed up in the photos. They aren’t extremely strong, but they’re definitely there.

Another interesting (at least to me) feature of the clouds Friday afternoon and evening was the way they changed. Late in the afternoon, but well before sunset, there were growing cumulus clouds everywhere. They had flat bottoms and billowing tops.

flat-bottom cloud

The bottoms of the clouds are all at about the same altitude, which is where the air from lower altitudes reaches saturation as it rises because of solar heating. At that point, water vapor starts to condense and form clouds. Condensation adds heat to the air, and it continues to rise. As it rises, more water vapor condenses and more latent heat is released. Under different conditions, these clouds could have eventually developed into thunderstorms. But, alas, none did, at least around us.

As the evening progressed and the solar heating decreased, the energy that drove these clouds’ development dissipated and the clouds began to change. There just wasn’t enough energy available to drive any more development once the sun went down. The flat bottoms became ragged and the tops stopped billowing. Some became closer to stratus clouds and others remained more like cumulus clouds. Eventually they turned into what we saw on our way home.

This is a panorama from our new house site made just as we reached home.

clouds_panoSome of these clouds still have billowy tops, but there was not much going on by this time.

 

Two thunderstorms, one night

Tuesday evening Leah and I noticed some dramatic clouds in the sky in two different places. I saw a yellow glow from the rear of the house and went outside on the deck to look. Off to the left, which is roughly east, I saw a cloud that was illuminated by the setting sun. It showed some fair vertical development.

clouds1

At the same time Leah was in the front. She called me out there and pointed to a cloud formation directly behind the house that I couldn’t see from the deck because of the trees. This was pretty much due south of us. It also showed some vertical development to the right in this image.

clouds2

Here is a panorama I shot with our little Nikon S9700, which has a built-in panorama function.

2thunderstorms

It looked like there was some rain beneath the cloud to the east, but it was late enough that it was hard to tell. A little later, after the sun had set completely, I went out onto the deck and saw this.

This was not a severe thunderstorm, so the lightning strokes were infrequent. I edited the video to get several strokes into a short period.

This was what my phone’s weather radar app showed at the same time. The red pushpin is our location.

radarimage

You can see that both cloud formations were producing rain, although not heavy rain.

You can see in the first two images that there was no anvil formation on either cloud, so they were not exceptionally high. I tried to do some rough calculations of the height of the cloud to the east, which was just south of downtown Rome. I had to estimate its distance and the elevation angle to the top of the cloud. I figure that the cloud top was somewhere between 14,000 and 19,000 feet. That sounds reasonable for the early development stages of a not-particularly severe thunderstorm.