Shreveport is located on the west side of the Red River, opposite Bossier City, in the northwestern section of Louisiana, some thirty miles south of Arkansas, and fifteen miles east of Texas. A portion of the city is situated in the Red River bottom lands, and the remainder is in gently rolling hills that begin about one mile west of the river.
The National Weather Service office is at the Shreveport Regional Airport, about eight miles southwest of the downtown area. Elevations in the Shreveport area range from about 170 to 280 feet above sea level.
The climate of Shreveport is transitional between the subtropical humid-type prevalent in the South and the continental climates of the Great Plains and Midwest to the north. During winter, masses of moderate to severely cold air move periodically through the area. The spring and fall seasons are usually mild, while the summer months are consistently hot and humid, with high pressure and a moist southerly flow being the dominant features. Rainfall is abundant with the normal annual rain just over 51 inches, with monthly averages ranging less than 3 inches in August to more than 5 inches in May and June. The average growing season for northwest Louisiana ranges between 230 and 240 days in length.
The majority of rainfall is convective in nature and air mass types-showers and brief-except during winter when nearly continuous frontal rains may persist for a few days. Extremes of precipitation occur in all seasons. While torrential rainfall is the exception in the Shreveport area, some heavy rainfall events of note are 12.44 inches in a 24-hour period on July 24-25, 1933, and 19.08 inches over a 3-day period on July 23-25, 1933. The July 1933 total of 25.44 inches the greatest monthly total. The greatest annual rainfall total of record was in 1991 with 81.99 inches, and the driest year on record was 1899 with 23.10 inches. The months with the fewest days of rain are August and October, with August having the least average precipitation.
The winter months are normally mild, with cold spells generally of short duration. The typical pattern is to turn cold one day, reaching the lowest temperature on the second day, and a warming trend on the third day. The coldest temperature on record at Shreveport is -5 degrees F on February 12, 1899. Temperatures of freezing or below occur each winter with an average of 39 days during the year. Temperatures drop below 15 degrees F only about one out of every two winters. The average date of the freeze (32 degrees F or lower) in the fall is November 15, and the average date of the last freeze in the spring is March 10. Freezing temperatures have been recorded as early as October 19 and as late as April 11. Temperatures recorded at the National Weather Service office on clear, calm nights are normally two to five degrees warmer than those in the low-lying river bottom lands of the area.
Measurable snowfall amounts occur on an average of only once every other year; many consecutive years may pass with no measurable snowfall. The heaviest snowstorm of record in the Shreveport area is 11.0 inches in December of 1929. This fell on the 21st and 22nd, and one-half inch remained on the ground on December 25th making this the only Christmas Day on record with snow on the ground. In 1948, 12.4 inches of snow was measured for the month of January for the greatest monthly amount on record. Occasional ice and sleet storms do considerable damage to trees, power and telephone lines, as well as make travel very difficult.
The summer months are consistently quite warm, with maximum temperatures exceeding 100 degrees F about 6 days per year, exceeding 95 degrees F about 32 days per year, and exceeding 90 degrees F about 87 days per year. The highest temperature on record is 110 degrees F on August 18, 1909. Showers and thunderstorms at any one location in the area give about eight days in a month of measurable rainfall. The resulting point rainfall totals are usually less than one-half inch except on two or three days per month when heavier amounts are recorded.
Thunderstorms occur each month, but are most frequent in spring and summer months. The showers and thunderstorms during the spring and autumn months are most often produced by squall lines and fronts, and are generally heavier than the air mass showers, which occur in the summer months. Severe local storms, including hailstorms, tornadoes, and local wind storms have occurred over small areas in all seasons, but are most frequent during the spring months, with a secondary peak from November to early January. Large hail of a damaging nature is infrequent, although hail as large as grapefruit fell in March 1961, and baseball size hail fell in May 1974 and April of 1995.
The average relative humidity is rather high in all seasons. These high humidity values may be experienced at any hour, but occur mainly during the early morning hours, with two-thirds of the hours shortly before sunrise having relative humidity of 90 percent or higher. In contrast, more than half of the mid-afternoon hours have had relative humidity values of less than 50 percent.
Tropical cyclones are in the dissipating stages by the time they reach this portion of Louisiana, and winds from them are usually not a destructive factor. Rainfall accompanying these systems can be heavy and can contribute to local flooding.
Thunderstorms accompany rain on average of 57 days a year.
SNOWFALL
Maximum in 24 hours
11.0 inches on December 21-22, 1929
Maximum in Storm Total
11.0 inches on December 21-22, 1929
Maximum in 1 Month
12.4 inches in January 1948
Maximum in 1 Season
15.4 inches in 1929-1930
Maximum Depth Measured
11.0 inches on December 22, 1929
Measurable snow occurs on average once every two years.
The only Christmas with snow on the ground was December 25, 1929.
ATMOSPHERIC PRESSURE
Highest on Record
30.95 inches on January 5, 1924 and January 10, 1929.
Lowest on Record
29.04 inches on February 27, 1902
WIND
Winds greater than 40 mph occur on the average of 12 days a year.
Winds greater than 58 mph (severe) occur on the average of 4 days a year.
Winds greater than 75 mph occur on average of 1 day a year.
Maximum Observed Wind Speed at
Shreveport Regional Airport
87 mph on November 23, 1983.
Second Highest Observed Wind Speed at
Shreveport Regional Airport
83 mph on May 3, 1991
Third Highest Observed Wind Speed at
Shreveport Regional Airport
81 mph on April 12, 1991
and May 27, 2000
Although not related to a tornado, a 144 mph wind gusts was recorded at Barksdale Air Force Base in Bosier City on April 22, 1997, as a result of a bow echo squall line moving eastward along the Interstate 20 Corridor of Northeast Texas and Northern Louisiana.
TORNADOES
33 tornadoes have occurred within a 15-mile radius of Shreveport-Bossier City since 1916.
9 of these were "killer" tornadoes.
Peak winds are estimated, but based on damage, 17 of these tornadoes produced peak winds less than 112 mph (EF0, EF1), while another 10 produced winds of 112-157 mph. Three of these tornadoes produced winds in excess of 206 mph. These three tornadoes received ratings of F4 under the old Fujita Scale. The Enhanced Fujita Scale was not commissioned until 2007. Under the new scale, wind speeds above 200 mph would be in the EF5 category.
Here are a few significant tornadoes occurring within or very near the
Shreveport/Bossier City area:
October 29, 2009 - Downtown Shreveport to North Bossier City (EF2)
April 9, 2009 - Near Waskom to Cross Lake to Downtown Shreveport
to Bossier City to Haughton (EF2)
April 23, 2000 - Greenwood to Keithville to Southern Trace (South Shreveport) to Elm Grove (F3)
April 23, 2000 - Cross Lake to Downtown Shreveport to Bossier City (F1)
April 3, 1999 - North Shreveport, Benton, Black Cypress Bayou (F4)
January 23, 1996 - South and Southeast Shreveport (F2)
December 3, 1978 - Bossier City (F4)
Significant Tornadoes Within a 15-Mile Radius of Shreveport-Bossier City
October 29, 2009 - Downtown Shreveport to North Bossier City (EF2)
April 9, 2009 - Near Waskom to Cross Lake to Downtown Shreveport to Bossier City to Haughton (EF2)
April 23, 2000 - Greenwood to Keithville to Southern Trace (South Shreveport) to Elm Grove (F3) and Cross Lake to Downtown Shreveport to Bossier City (F1)
The Easter Sunday Tornado Outbreak of April 23, 2000, produced 28 tornadoes across the Four State Region. The largest documented tornado outbreak in one day for this area. Although there were a large number of tornadoes that day, there was no loss of life. Four tornado touchdowns were noted across Caddo and Bossier Parishes with this outbreak. Two of these tornadoes impacted portions of Shreveport, causing moderate to severe damage in the northern and southern sections of town. The tornado that struck North Shreveport developed over Cross Lake (as a waterspout) and moved onto land (as a tornado), and moved eastward into Downtown Shreveport causing F1 damage. A second tornado (F2) developed near Greenwood and tracked eastward into South Shreveport (near Stagecoach Road) destroying several homes and causing extensive damage across South Shreveport, before crossing the Red River into Southern Bossier Parish. This tornado intensified as it crossed the river (F3) causing severe damage just south of Elm Grove. In addition, golfball to softball sized hail was reported over much of Shreveport and Bossier City as these storms rolled through.
April 3, 1999 - North Shreveport, Benton, Black Cypress Bayou (F4)
The North Shreveport-Benton-Black Cypress Bayou tornado of April 3, 1999, produced winds in the F4 category in Bossier Parish, with estimated maximum winds of about 230 mph. This tornado killed 7 people and injured 93 as it tracked through the Hay Meadow Mobile Home Park and the Black Cypress Bayou areas in Bossier Parish. It destroyed over 250 homes. At Hay Meadow, 66 of the 100 mobile homes were completely destroyed.
November 15, 1987 - Northeast of Center, TX, to South Shreveport
The November 15, 1987, tornado that struct from northeast of Center, TX, to South Shreveport, likely produced a wind gust of 222 mph, 18 miles south-southwest of Shreveport, near Crossroads in DeSoto Parish. At this point, it lifted a 9710-pound Ford tractor front-end loader and dropped it some 1890 feet downwind. Based on other effects, the storm winds decreased to 150 mph along the Highway 171 west side of Western Electric when it demolished 2 houses and 1 store. The wind assessment was based on steel beams. The storm then moved across 171 and turned left, destroyed an entire mobile home park (40 homes). The wind gusts had probably decreased to 85-100 mph when it reached the Southern Hills subdivision in South Shreveport.
December 3, 1978 - Bossier City (F4)
The Bossier City tornado of December 3, 1978, produced an effective wind gust of about 218 mph in two areas.
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