Middle Tennessee Weather News
A Publication of the National Weather Service in Old Hickory
Serving Middle Tennessee Since 1870
Fall Edition, September 1, 2005, Volume IV, Issue III
Mark A. Rose, Editor
Hurricane Katrina
During the morning of August 30, the remnants of Hurricane Katrina tracked across extreme northwestern Middle Tennessee, passing directly over Clarksville. This placed almost all of Middle Tennessee in the dreaded northeast quadrant of the storm during the previous evening and early on the morning of the 30th. The NWS issued a rare inland tropical storm watch/warning for Middle Tennessee prior to the event.
Several Middle Tennessee locations recorded wind gusts of 30 and even 40+ miles an hour, with several hours of sustained winds of 20+ miles an hour. As a result of the wet ground and strong winds, wind damage was reported in 33 of the 39 counties served by the Old Hickory office.
In additon, 48-hour rainfall totals ending at 7:00 a.m. on August 31 were topped by White House's 5.58 inches. Other amounts in excess of four inches were: Springfield, 5.44, Dover, 5.38, Dickson, 5.24, Gladeville, 5.17, Fairview, 5.09, Joelton, 5.07, Mt. Juliet, 4.97, Hohenwald, 4.88, Lobelville, 4.84, Montgomery Bell State Park, 4.80, Smyrna, 4.72, Coalmont, 4.50, Lawrenceburg, 4.46, Old Hickory NWS, 4.37.
The Nashville International Airport recorded a storm total of 2.52 inches, bringing the monthly total to 6.89. This makes August, 2005 the ninth wettest in 135 years of record-keeping.
Fall Outlook and Climatology for Nashville
The seasonal outlook from the National Weather Service's Climate Prediction Center for the three-month period of September through November (the "meteorological fall") calls for near normal temepratures and precipitation for Middle Tennessee. The following table gives both the normal and extreme values of various meteorological variables observed at Nashville.
| Sep | Oct | Nov
| Normal Temperature | Warmest Month | (1925) (1919) (1909) Coolest Month | (1918) (1952) (1976) Record High | (5/1954) (1/1953) (1/1935) Record Low | (30/1949) (22/1983) (24/1983) (29/1925) (30/1952) (22/1987) (25/1950) Normal Precipitation | Normal Snowfall | Wettest Month | (1979) (1919) (1945) Driest Month | (1903) (1963) (1949) |
|---|
Photograph of the Quarter
Sharon Prince of Huntland writes "Took these pictures at 8:00 p.m. [July 6]. This is looking southeast. The sun had slipped below the horizon just a few minutes before."
If you have a unique weather photograph you would like to share, please either e-mail it to the editor, or send it to: National Weather Service, 500 Weather Station Rd., Old Hickory, TN 37138, Attn: Mark A. Rose. If you mail your photograph(s), I will scan them and mail them right back.
Mayor's First Day
On Sunday, August 14, 2004, Michael Davis, our Information Technology Officer, partnered with the Nashville Office of Emergency Management to participate in the sixth annual Mayor's First Day at the Gaylord Entertainment Center in downtown Nashville. The event is hosted by the Mayor of Nashville on the day before students return to school.
An estimated crowd of 12,000 toured the center between 2:00 PM and 5:00 PM, as a number of local organizations set up educational displays and distributed free items to the public. This was NWS Old Hickory's second largest outreach event ever. The highlight of the weather service's display was a tornado machine. Several educators made requests for us to give weather talks at their schools.
Before Katrina, there was a drought
Entering the driest time of the year for Middle Tennessee, I thought that drought might be a good topic for the hydrology section of our fall newsletter.
First of all, drought is a normal, recurrent feature of our climate. It occurs almost everywhere, although its features vary from region to region. Defining drought is therefore difficult and depends on differences in regions. In the most general sense, drought originates from a deficiency of precipitation over an extended period of time, resulting in a water shortage for some activity, group, or environmental sector.
There are four types or categories of droughts. Meteorological Drought is defined as a deficiency of precipitation due to atmospheric conditions. Agricultural Drought is when soil moisture deficiencies affect food production and farming. Hydrological Drought occurs when water systems such as rivers and reservoirs are below supply levels. Socioeconomic Drought is when water supply is not sufficient to meet human and environmental needs.
One of the worst drought periods for the Cumberland River Basin of northern Middle Tennessee occurred in the mid to late 1980's. During the four year period of 1985-1988, Nashville's rainfall deficit totaled nearly 59 inches. One of the worst single-year droughts in the Cumberland Basin occurred in 1941.
Before Katrina, this had been a dry year for most of Middle Tennessee. At Nashville, the rainfall deficit from January 1 through August 28 was between 2 and 3 inches. On the Cumberland Plateau at Crossville the rainfall deficit was nearly 5 inches, although this region received only around an inch of rainfall during Katrina. Both May and June were especially dry months at most locations. In fact at Nashville, May, 2005 was the driest May since 1951, and the third driest May on record. Several reporting stations across Middle Tennessee received less than one inch of rain during May. June was also drier than normal for a large part of Middle Tennessee. The exception was across western Middle Tennessee, where between 2 and 3 inches of rain fell as Tropical Storm Arlene moved across the region. July brought a slight reprieve from the dry conditions. Periods of showers and thunderstorms as well as rainfall from Hurricane Dennis helped to lessen rainfall deficits, low soil moisture content, and low stream levels. Through the first half of August, typical summertime shower and thunderstorm activity has provided some locations with ample rainfall while others remain relatively dry.
Drought conditions have plagued several regions of the U.S. during the summer of 2005. Areas hardest hit extend from the Great Lakes through the northern half of Illinois, central Missouri and Arkansas, and northeast Texas. These areas have experienced moderate to extreme drought conditions for most of the summer.
The eastern half of Kentucky and southern Ohio have also experienced drought conditions for most of the summer. Portions of the western U.S. are in the midst of a drought. Areas from the northern Great Basin and northern Rockies into the northern Plains are experiencing a severe drought. The southern Rockies and parts of the desert Southwest are considered to be in a moderate drought.
The latest seasonal drought outlook indicates that some additional improvement is likely over the drought area extending from the Great Lakes into northern Missouri. Improvement is also expected for the drought areas in Arkansas and Texas. Across Kentucky and Ohio, drought conditions are expected to persist into autumn. Drought will likely continue in the Northwest while seasonal monsoon rains will provide some relief in the Southwest.
During climate extremes, whether drought or flood, agriculture usually suffers first and most severely, yet eventually everyone feels the impact. For more information and updates on drought conditions, visit the U.S. Drought Monitor webpage at http://drought.unl.edu/dm/monitor.html.
Mike Murphy
Service Hydrologist