Monday, November 30, 2015

A Man with His Head In the Clouds

Altocumulus clouds. Photo by Steve Hilberg
One of the most fascinating aspects of weather and the most visible is clouds. Clouds are the telltale indicators that provide clues to what the weather is and may be doing. Nothing may be more frustrating to a meteorologist or weather fan than not having access to a window through which to observe the sky.

Most of us learned about the basic types of clouds some time in school. Clouds fall into general classifications as high, middle, low, or accessory clouds. You may be familiar with some of the specific names, such as cirrus, stratus, and cumulonimbus. What you may not be familiar with is how clouds got their names.

Luke Howard (1772-1864)
In 1802 an English pharmacist and pharmaceutical manufacturer with a lifelong interest in meteorology proposed a cloud classification system in a paper presented to the Askesian Society, a debating club for scientific thinkers in London. The paper, "Essay on the Modification of Clouds", was published in 1803. The man, Luke Howard, was trained as a business man but had a passion for the weather. In the paper he named the three major classifications of clouds - cirrus, stratus, and cumulus, as well as all of the modifications and intermediate stages of clouds.

Drawing of clouds from Luke Howard's sketchbook.
Howard was not the first to propose a cloud classification system. Years earlier a French man, Jean-Baptiste Lamarck, proposed a cloud description regime in French. Howard grounded his classification scheme in Latin, which led to it being more readily accepted than other proposed classifications. He used the same taxonomy classification principles used in the field of natural history to classify plants and animals. Like animal or plant taxonomy, clouds are classified in terms of genus, family, species,and varieties. He realized that clouds were the windows to the state of the atmosphere.

Howard's contributions to meteorology weren't limited to clouds. He was the first to document the urban heat island, noting that temperatures in London were warmer at night than the surrounding countryside and cooler during the day. Howard published The Climate of London which documented continuous observations of temperature, rainfall, and air pressure. He presented seven lectures on meteorology and wrote other articles on the topic. Howard was named a Fellow of the Royal Society in 1821, the highest scientific honor at that time, for his work in meteorology.

You can read more about Luke Howard in the following articles: Luke Howard --"The Godfather of Clouds", a web site created by Dr. John Day. The Royal Meteorological Society has a web page, "Luke Howard and Cloud Names"

Cloud enthusiasts have a number of outlets and resources available. The Cloud Appreciation Society promotes interest in and photography of clouds. The Society connects clouds lovers across the world, and is the web site for everything clouds. 

On Facebook the Community Cloud Atlas is a page where participants can post cloud photos and get help identifying clouds. is an online cloud atlas that goes into detail on describing the taxonomy of clouds, including photographs and the ability to upload cloud photos.

Keep your eyes on the sky - you never know what you might see!

An approaching shelf cloud. Photo by Steve Hilberg

Wednesday, November 18, 2015

The Weather This Week - All Sorts of Crazy

The weather system currently crossing the country has produced an astounding amount of interesting and severe weather so far, from torrential rain to tornadoes and blizzard conditions.

The system came ashore along the west coast on Sunday and strengthened over the western U.S on Monday. The surface low began to become organized over the Rockies as the deep upper level trough developed a cutoff over the southwest U.S. Cold air on the west side of the system, warm, moist air streaming northward on the east side, and strong winds aloft combined to produce a volatile atmosphere.

500 millibar map (~20,000 ft) for November 16, 6:00 p.m.
Surface weather map for Tuesday, November 17, 2015 at 6:00 a.m. CST
Early in the day the Storm Prediction Center identified an area from northern Texas into Nebraska as in a Slight Risk for severe weather, with a smaller Enhanced Risk over northwest Texas and western Oklahoma.
Convective Outlook for Tuesday, November 17 issued at 8:00 a.m.CST

Meanwhile, a Blizzard Watch was upgraded to a Blizzard Warning over eastern Colorado, including the Denver area. Later in the day Tornado Watches were issued covering areas from the Texas Panhandle into Nebraska. In Colorado areas in the Blizzard Warning were only 90 miles or so from other parts of Colorado in a Tornado Watch.

24-hour snowfall ending the morning of November 17. The orange-red area in southwest Colorado is 15-18 inches

Supercell thunderstorms did eventually develop during the late afternoon and evening from northwest of Amarillo, TX to west of Dodge City, Ks, and further north into Nebraska. A number of large tornadoes were spawned by these storms. One tornado near Pampa, TX produced EF-3 damage. Surveys are being conducted on other tornadoes that touched down. In western Kansas nine tornadoes touched down, including one which was on the ground for 78 minutes and 51 miles and produced EF-3 damage near Kismet.

Storm reports from 6:00 a.m. 11/16/2015 to 6:00 a.m. 11/17/2015

The tornado outbreak that occurred Monday night from western Texas into far southern Nebraska was very rare for the west-central Plains in November. This may have been the greatest number of tornadoes on a given November day so far west in the Plains dating back to 1900.

Cold, wind, and snow came in on the heels of the severe weather. Twelve to 18 inches of snow fell in northwestern Kansas, with lesser amounts in western Nebraska. Howling winds spinning around the intensifying low pressure system whipped up the snow creating blizzard conditions from the eastern plains of Colorado into western Kansas. A large portion of Interstate 70 in eastern Colorado and western Kansas was closed due to the dangerous conditions on Tuesday.

48-hour snowfall accumulation ending the morning of November 18, 2015. 12 to 18 inches of snow were  reported by observers in western Kansas.

Today, winds were the big news from the the Rockies and northern and central Plains east through the Midwest. This occurred as the central U.S. low pressure system intensified as it merged with another low that moved in the the Pacific Northwest yesterday. This Pacific system produced damaging winds across Washington state. Today winds gusted in excess of 100 mph in a few locations in Colorado, 94 mph in Boulder and the National Center for Atmospheric Research, and 77 mph in Fort Collins where CoCoRaHS headquarters is located.

Surface map at 3:00 p.m. CST November 17. The Central Plains low is starting to intensify. The system that merged with it today can be seen over Washington and British Columbia.

 The amount of moisture being transported by the central U.S. storm system was phenomenal. There was a conveyor belt of atmospheric moisture from the Gulf of Mexico north to Hudson Bay in Canada.
Water vapor satellite image On Tuesday, November 17 at 11:15 a.m. CST. The pink and blue colors indicate moisture, while the orange and red colors depict dry air. The west side of the upper level trough is clearly seen along the Rockies, as is the center of the closed low over Texas and Oklahoma panhandles.

On Tuesday evening the NWS Quad Cities office (Iowa/Illinois) reported a record high amount of precipitable water for November, 1.50 inches, measured by the evening atmospheric sounding. This moisture, along with the strong lift generated by the intense low pressure system aloft resulted if copious amounts of precipitation from Texas to Illinois, and east through the Gulf States. Three to four inch amounts were common from southern Missouri south to Louisiana and east through Mississippi.

Today the severe weather focus was in the southeast U.S., and this afternoon tornadoes touched down in the Florida panhandle and near Atlanta, GA.

Surface map at 3:00 p.m. CST Wednesday, November 18.

On Thursday the low now over the Northern Plains will be near the southern end of Hudson Bay, while the front pushes slowly off the east coast, and most of the country should see some quiet weather for 24 hours or so.

Monday, November 9, 2015

The "Community" in CoCoRaHS

In the fall of 2008 I conducted a CoCoRaHS training session in a small county in east-central Illinois in my role as Illinois Coordinator. It was surprisingly well-attended, though in the end we only picked up two observers out of the group. One in particular came up to see me after the presentation. He introduced himself as Max and we spent a few minutes talking about weather and weather observations. He told me how he had been keeping his own weather observations for 30 years or more and it was something he was passionate about. Max was excited to finally have somewhere to report his observations. The only problem was that he did not use a computer or the Internet. For all of the years he had been taking observations he recorded them by hand in notebooks. As far as I was concerned, that wasn't a problem. We made an arrangement that he would mail me his observations at the end of the month, and I would then enter them into the CoCoRaHS database. So began our relationship.

Each month, as promised, Max would send me the previous month's observations and I would enter them in the database. I'd then print them off and send them back to him along with our monthly newsletter. Max would usually call me each month to make sure I received his observations and see if I had any questions about them. As our monthly phone conversations progressed our chats branched out to mutual interests (fishing, for one). Max was an avid outdoorsman. He loved to fish, hunt, hunt for mushrooms and go camping. One of his favorite spots to camp was the Shawnee National Forest in southern Illinois and he told me about a number of his experiences there. He was coordinator for his county bluebird society. Every year Max maintained more than 200 bluebird nesting boxes in east-central Illinois and western Indiana. They would be cleaned out during the winter and early spring, and then he would check them periodically to see how many baby bluebirds were hatched, recording the information at each nesting box.  Max was most proud of his efforts with the bluebirds.

About two years ago Max developed a few health issues, but he didn't let that slow him down much. He enlisted the help of friends to read his rain gauge when he couldn't get outside, and to drive him around to check his bluebird boxes. He also had a friend transcribe his rainfall observations to the form he sent me every month. He would call to assure me the observations were coming, even if they might be late, and then call again to be sure I got them.

Max submitted his first CoCoRaHS observation on November 20, 2008. He had only a few missing observations until this spring, when health issues prevented him from observing in March. He picked it right up again, however, and didn't miss a day the rest of the spring and summer.

I was saddened to learn today that Max passed away a few weeks ago. I really looked forward to his calls each month and will miss our conversations. I only met Max in person that one time, but over the next six plus years we developed a relationship through our conversations and common interests. I often thought, after our phone calls, that this is part of what the "community" aspect of CoCoRaHS is about.

Rest in peace, Max.