2001 Shreveport, Louisiana (SHV)

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2001 SHREVEPORT, LOUISIANA (SHV)

Shreveport is located on the west side of the Red River, opposite Bossier City, in the northwestern section of Louisiana, some 30 miles south of Arkansas and 15 miles east of Texas. A portion of the city is situated in the Red River bottom lands and the remainder in gently rolling hills that begin about 1 mile west of the river. The NOAA National Weather Service Office is at the Shreveport Regional Airport, about 8 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 to the south and the continental climates of the Great Plains and Middle West 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 quite warm and humid with high pressure and a moist southerly flow being the dominant feature. Rainfall is abundant with the normal annual just over 46 inches, with monthly averages ranging less than 3 inches in August to more than 5 inches in May. The average growing season for northwest Louisiana ranges between 230 and 240 days in length.

The majority of rainfall is of convective and air mass types–showery 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 notes are 12.44 inches in a 24–hour peroid on July 24–25, 1933, and 19.08 inches over a three–day peroid on July 23–25, 1933. The July 1933 total of 25.44 inches was the greatest monthly total. The greatest annual rainfall of record was in 1991 with 81.99 inches, and the driest year of 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 turning cold one day, reaching the lowest temperature on the second day, and a warming trend on the third day. The coldest reading on record 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 first 32 degrees F 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 NWS Office on clear, calm nights are normally 2 to 5 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 consecuitive 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 December 25th, making this the only Christmas Day of 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 about 6 days per year, exceeding 95 degrees about 32 days per year, and exceeding 90 degrees 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 windstorms 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 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 the state and winds from them are usually not a destructive factor. rainfall accompanying these systems can be heavy and can contribute to local flooding.

NORMALS, MEANS, AND EXTREMES

SHREVEPORT, LA (SHV)

LATITUDE:    LONGITUDE: ELEVATION (FT): TIME ZONE: WBAN: 13957

32 26′ 49″ N  93 49′ 27″ W  GRND: 271  BARO: 274  CENTRAL (UTC + 6)

ELEMENTPORJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECYEAR
TEMPERATURE FNORMAL DAILY MAXIMUM3055.460.669.277.183.289.793.093.187.378.768.058.576.2
MEAN DAILY MAXIMUM5456.261.468.676.983.590.193.393.487.678.567.158.876.3
HIGHEST DAILY MAXIMUM4984899294102102107109109978884109
YEAR OF OCCURRENCE197219861974198719981998199820002000195419841955SEP 2000
MEAN OF EXTREME MAXS.5476.579.684.187.291.895.798.9100.196.590.782.876.988.4
NORMAL DAILY MINIMUM3034.838.045.854.162.069.072.371.366.054.345.337.354.2
MEAN DAILY MINIMUM5436.439.846.054.262.869.672.771.666.054.644.838.354.7
LOWEST DAILY MINIMUM4931220314252585342281653
YEAR OF OCCURRENCE196219781980198919601977197219921984199319761989JAN 1962
MEAN OF EXTREME MINS.5418.923.328.838.249.559.766.664.251.938.428.221.440.8
NORMAL DRY BULB3045.149.357.565.672.679.482.782.276.766.556.748.065.2
MEAN DRY BULB5446.350.557.365.673.279.983.082.676.866.555.948.565.5
MEAN WET BULB1742.046.851.658.767.172.675.074.168.960.151.644.559.4
MEAN DEW POINT1736.440.845.653.563.569.471.870.365.055.947.039.554.9
NORMAL NO. DAYS WITH:
MAXIMUM 90300.00.0*0.33.717.225.025.013.32.50.00.087.0
MAXIMUM 32301.30.4*0.00.00.00.00.00.00.00.00.62.3
MINIMUM 323014.18.32.50.20.00.00.00.00.00.22.710.838.8
MINIMUM 0300.00.00.00.00.00.00.00.00.00.00.00.00.0
H/CNORMAL HEATING DEG. DAYS306234482626900000632645352264
NORMAL COOLING DEG. DAYS306830872394325495333511101582368
RHNORMAL (PERCENT)3073706870737372727472747472
HOUR 00 LST3078767679848483838482828181
HOUR 06 LST3084848487909190919189878688
HOUR 12 LST3063605656595958565854596358
HOUR 18 LST3065585456606058586262686861
SPERCENT POSSIBLE SUNSHINE4852575860647275757070605464
W/OMEAN NO. DAYS WITH:
HEAVY FOG (VISBY 1/4 MI)493.32.21.41.31.00.50.30.40.92.22.83.119.4
THUNDERSTORMS492.22.95.25.57.27.58.16.54.33.03.12.257.7
CLOUDINESSMEAN:
SUNRISE-SUNSET (OKTAS)12.41.6
MIDNIGHT-MIDNIGHT (OKTAS)12.4
MEAN NO. DAYS WITH:
CLEAR16.05.010.06.07.0
PARTLY CLOUDY12.03.07.08.0
CLOUDY13.02.07.03.04.0
PRMEAN STATION PRESSURE(IN)2829.8629.8229.7329.7029.6729.6929.7329.7329.7429.7929.8229.8629.76
MEAN SEA-LEVEL PRES. (IN)1730.1530.0930.0329.9729.9429.9530.0129.9930.0130.0730.1130.1530.04
WINDSMEAN SPEED (MPH)429.39.69.99.88.67.77.06.77.27.38.59.08.4
PREVAIL. DIR (TENS OF DEGS)2718181818181818181214161318
MAXIMUM 2-MINUTE:
SPEED (MPH)638435445634141403237403663
DIR. (TENS OF DEGS)28342926322915113225293032
YEAR OF OCCURRENCE199920011999199920001998199819981996200119982000MAY 2000
MAXIMUM 5-SECOND:
SPEED (MPH)646526855815567594146514581
DIR. (TENS OF DEGS)26283126323118343325293032
YEAR OF OCCURRENCE200019991999199920001998199819971996200119962000MAY 2000
PRECIPITATIONNORMAL (IN)303.883.923.593.755.184.293.672.433.123.734.454.1046.11
MAXIMUM MONTHLY (IN)4912.968.578.7221.8411.7817.119.469.239.5912.0510.8110.0021.84
YEAR OF OCCURRENCE199919831997199119671989197219911968198419871982APR 1991
MINIMUM MONTHLY (IN)490.270.420.560.430.150.130.150.350.080.000.520.590.00
YEAR OF OCCURRENCE197119991966198719981988196420001994196319991981OCT 1963
MAXIMUM IN 24 HOURS (IN)497.003.533.6310.445.277.284.404.645.393.886.513.9410.44
YEAR OF OCCURRENCE199919651979199119781993199519551961195719872001APR 1991
NORMAL NO. DAYS WITH:
PRECIPITATION 0.01309.48.19.38.29.07.97.96.67.06.68.19.597.6
PRECIPITATION 1.00301.21.21.11.21.81.31.21.01.01.21.41.114.7
SNOWFALLNORMAL (IN)301.00.60.20.*0.00.00.00.00.00.00.*0.32.1
MAXIMUM MONTHLY (IN)495.94.44.00.3T0.00.0T0.0T1.35.45.9
YEAR OF OCCURRENCE197819851965198719941997199219801983JAN 1978
MAXIMUM IN 24 HOURS (IN)495.64.44.00.3T0.00.0T0.0T1.35.45.6
YEAR OF OCCURRENCE198219851965198719941997199219801983JAN 1982
MAXIMUM SNOW DEPTH (IN)539420000000139
YEAR OF OCCURRENCE19481951196519801963JAN 1948
NORMAL NO. DAYS WITH:
SNOWFALL 1.0300.30.20.10.00.00.00.00.00.00.00.*0.10.7
PRECIPITATION (inches) 2001 SHREVEPORT, LA (SHV)
YEARJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECANNUAL
19725.970.942.452.064.132.769.461.272.106.325.324.1846.96
19735.651.525.016.442.005.847.630.776.395.385.166.3758.16
197410.093.673.603.094.586.297.733.846.643.795.802.3461.46
19754.554.515.843.915.313.483.451.650.983.874.441.8843.87
19762.072.456.671.755.954.423.472.966.282.081.633.7743.50
19773.003.684.942.052.402.413.894.280.530.312.112.5832.18
19784.891.902.662.797.921.211.743.902.402.744.185.1341.46
19799.224.985.747.427.993.047.501.864.333.964.763.1263.92
19804.673.103.755.344.422.601.830.421.632.483.590.7434.57
19811.433.833.331.979.966.452.360.943.325.631.490.5941.30
19823.593.192.592.722.321.844.252.201.115.195.7210.0044.72
19832.458.573.681.478.226.601.181.673.120.794.907.1849.83
19842.105.663.582.525.863.562.200.872.6112.054.462.8848.35
19852.384.424.283.051.964.578.400.354.409.874.253.3751.30
19860.493.480.753.506.6014.672.921.683.516.639.194.6958.11
19872.267.801.480.436.675.431.213.500.945.4910.818.1254.14
19882.063.593.893.450.420.133.123.521.614.445.444.7136.38
19897.204.063.412.4110.0717.114.463.941.081.502.323.3460.90
199010.026.924.904.2910.482.563.532.882.934.338.813.9965.64
19917.705.132.8921.8410.712.533.479.233.453.593.947.5181.99
19924.636.415.943.262.813.953.361.245.154.134.695.8451.41
19934.634.805.944.193.3015.730.274.093.514.434.851.4457.18
19943.635.023.673.675.852.816.433.800.089.142.508.0054.60
19955.443.754.057.803.261.095.680.833.361.651.945.1143.96
19962.120.642.333.860.936.505.705.787.171.665.872.2444.80
19974.478.098.7211.933.196.141.735.482.417.503.446.1069.20
19985.847.194.280.790.151.352.843.837.795.724.586.2450.60
199912.960.425.107.883.967.982.801.474.903.210.523.8255.02
20002.602.317.905.6710.767.321.05T1.131.659.937.5657.88
20015.766.526.470.864.317.331.754.106.845.174.166.1059.37
POR=YRS4.243.774.234.694.623.703.472.652.923.253.964.5446.04
AVERAGE TEMPERATURE (F) 2001 SHREVEPORT, LA (SHV)
YEARJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECANNUAL
197249.451.959.866.972.380.881.082.680.267.250.945.565.7
197344.749.560.962.071.778.581.178.274.968.261.546.864.8
197447.851.263.664.374.076.682.180.171.066.255.647.365.0
197550.248.455.663.772.478.280.980.773.768.056.349.364.8
197647.159.260.267.367.975.778.678.774.359.949.346.363.7
197737.350.859.665.574.179.583.580.378.766.356.547.365.0
197834.938.152.865.573.680.585.483.377.866.060.048.063.8
197937.446.659.166.070.278.081.280.374.267.052.848.963.5
198048.347.954.963.074.383.486.985.582.163.554.249.166.1
198144.749.856.070.069.280.282.881.373.965.056.846.964.7
198246.145.661.563.374.478.683.383.275.664.655.451.265.2
198344.648.855.059.770.077.482.384.075.766.755.937.563.1
198440.650.458.064.972.179.381.182.175.070.656.460.065.9
198540.046.261.467.072.879.383.184.876.368.561.544.265.4
198649.054.459.766.572.379.983.780.879.465.255.646.166.1
198744.851.755.764.275.379.182.385.376.764.156.150.265.5
198842.249.356.365.271.879.883.383.777.864.158.649.265.1
198951.545.856.765.673.876.781.281.073.766.558.640.864.3
199052.556.459.465.672.682.782.283.379.765.058.948.567.2
199144.252.060.068.675.380.682.681.275.768.752.151.266.0
199247.254.759.565.171.478.582.978.676.067.052.049.565.2
199346.449.355.261.370.780.284.684.877.364.452.049.164.6
199446.451.258.066.770.981.482.181.176.367.060.051.166.0
199548.153.159.464.673.979.084.286.677.366.255.049.166.4
199646.252.453.463.877.078.382.380.074.166.055.751.565.1
199745.651.261.460.370.378.183.681.078.266.851.946.064.5
199851.751.656.163.577.384.988.584.681.768.558.049.368.0
199951.657.056.469.472.079.882.985.975.365.558.849.667.0
200050.457.261.763.675.879.183.986.978.167.852.639.866.4
200143.453.253.469.274.679.084.582.374.663.359.651.165.7
POR=YRS47.050.757.965.973.280.383.082.677.167.056.148.965.8

REFERENCE NOTES:

PAGE 1:

THE TEMPERATURE GRAPH SHOWS NORMAL MAXIMUM AND NORMAL MINIMUM DAILY TEMPERATURES (SOLID CURVES) AND THE ACTUAL DAILY HIGH AND LOW TEMPERATURES (VERTICAL BARS).

PAGE 2 AND 3:

H/C INDICATES HEATING AND COOLING DEGREE DAYS.

RH INDICATES RELATIVE HUMIDITY

W/O INDICATES WEATHER AND OBSTRUCTIONS

S INDICATES SUNSHINE.

PR INDICATES PRESSURE.

CLOUDINESS ON PAGE 3 IS THE SUM OF THE CEILOMETER AND SATELLITE DATA NOT TO EXCEED EIGHT EIGHTHS (OKTAS).

GENERAL:

T INDICATES TRACE PRECIPITATION, AN AMOUNT GREATER THAN ZERO BUT LESS THAN THE LOWEST REPORTABLE VALUE.

+ INDICATES THE VALUE ALSO OCCURS ON EARLIER DATES.

BLANK ENTRIES DENOTE MISSING OR UNREPORTED DATA.

NORMALS ARE 30–YEAR AVERAGES (1961–1990).

ASOS INDICATES AUTOMATED SURFACE OBSERVING SYSTEM.

PM INDICATES THE LAST DAY OF THE PREVIOUS MONTH.

POR (PERIOD OF RECORD) BEGINS WITH THE JANUARY DATA MONTH AND IS THE NUMBER OF YEARS USED TO COMPUTE THE MEAN. INDIVIDUAL MONTHS WITHIN THE POR MAY BE MISSING.

WHEN THE POR FOR A NORMAL IS LESS THAN 30 YEARS, THE NORMAL IS PROVISIONAL AND IS BASED ON THE NUMBER OF YEARS INDICATED.

0.* OR * INDICATES THE VALUE OR MEAN–DAYS–WITH IS BETWEEN 0.00 AND 0.05.

CLOUDINESS FOR ASOS STATIONS DIFFERS FROM THE NON–ASOS OBSERVATION TAKEN BY A HUMAN OBSERVER. ASOS STATION CLOUDINESS IS BASED ON TIME–AVERAGED CEILOMETER DATA FOR CLOUDS AT OR BELOW 12,000 FEET AND ON SATELLITE DATA FOR CLOUDS ABOVE 12,000 FEET.

THE NUMBER OF DAYS WITH CLEAR, PARTLY CLOUDY, AND CLOUDY CONDITIONS FOR ASOS STATIONS IS THE SUM OF THE CEILOMETER AND SATELLITE DATA FOR THE SUNRISE TO SUNSET PERIOD.

GENERAL CONTINUED:

CLEAR INDICATES 0–2 OKTAS, PARTLY CLOUDY INDICATES 3–6 OKTAS, AND CLOUDY INDICATES 7 OR 8 OKTAS. WHEN AT LEAST ONE OF THE ELEMENTS (CEILOMETER OR SATELLITE) IS MISSING, THE DAILY CLOUDINESS IS NOT COMPUTED.

WIND DIRECTION IS RECORDED IN TENS OF DEGREES (2 DIGITS) CLOCKWISE FROM TRUE NORTH. "00" INDICATES CALM. "36" INDICATES TRUE NORTH.

RESULTANT WIND IS THE VECTOR AVERAGE OF THE SPEED AND DIRECTION.

AVERAGE TEMPERATURE IS THE SUM OF THE MEAN DAILY MAXIMUM AND MINIMUM TEMPERATURE DIVIDED BY 2.

SNOWFALL DATA COMPRISE ALL FORMS OF FROZEN PRECIPITATION, INCLUDING HAIL.

A HEATING (COOLING) DEGREE DAY IS THE DIFFERENCE BETWEEN THE AVERAGE DAILY TEMPERATURE AND 65 F.

DRY BULB IS THE TEMPERATURE OF THE AMBIENT AIR.

DEW POINT IS THE TEMPERATURE TO WHICH THE AIR MUST BE COOLED TO ACHIEVE 100 PERCENT RELATIVE HUMIDITY.

WET BULB IS THE TEMPERATURE THE AIR WOULD HAVE IF THE MOISTURE CONTENT WAS INCREASED TO 100 PERCENT RELATIVE HUMIDITY.

ON JULY 1, 1996, THE NATIONAL WEATHER SERVICE BEGAN USING THE "METAR" OBSERVATION CODE THAT WAS ALREADY EMPLOYED BY MOST OTHER NATIONS OF THE WORLD. THE MOST NOTICEABLE DIFFERENCE IN THIS ANNUAL PUBLICATION WILL BE THE CHANGE IN UNITS FROM TENTHS TO EIGHTS (OKTAS) FOR REPORTING THE AMOUNT OF SKY COVER.

HEATING DEGREE DAYS (base 65 F) 2001 SHREVEPORT, LA (SHV)
YEARJULAUGSEPOCTNOVDECJANFEBMARAPRMAYJUNTOTAL
1972–7300692419597621429135145902453
1973–740004016455753338615278201912
1974–75001432312541473457305124002258
1975–7600439286492551186202381701815
1976–7700019947157485139918846002728
1977–7800072260549933746374613003025
1978–7900057181528849517216501102409
1979–800005236649850849431296402330
1980–81003128340488620425279142002317
1981–82008129246554588537202125402393
1982–830091203094576244493081861202474
1983–84001569305848747421247811102744
1984–8500193628620877052815142102041
1985–8600114917463849033117644101914
1986–8700086299579618366286117002351
1987–880007927945670145327854102301
1988–890007621848241853529593202119
1989–9000178524474338224321692302025
1990–9100612620850963435719726602069
1991–9200936401422544297185842302001
1992–9300233381480569435307154302364
1993–94005132404490577392239812002340
1994–9500574179440528334224801001874
1995–96001056311507576387372115202336
1996–97001059277427604383133157502055
1997–980009539258040636832488002253
1998–990003721550142225026141101728
1999–0000279189477462247149103001708
2000–0100107038877466233235235002623
2001–005118175441
COOLING DEGREE DAYS (base 65 F) 2001 SHREVEPORT, LA (SHV)
YEARJANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDECANNUAL
1972221031128235480501553467167102595
19730216642234125044173051456602154
19747611563288355541477200773502164
1975230219123840350149327114134122228
19762265811611232642843228848701843
19770728692894435804794191191292454
197850384303472637570391963982608
1979083986178395509483284124822116
198016643298560686643522862212874
19810510171157463558511284135602300
1982140998130041357357333311524322557
1983007341763815405953431263902241
198405388323543651154032921935612492
198508491092524365686203561637802639
198624117952364545864944381012402488
198710799327431544634357571952481
1988331467220449575587390533712399
198987431212833585085032861405702314
199029501152445385365724531323032684
199101471413344755505093361582052576
199204219322741256142833999142189
19930010501894616146203811212042470
19943122914120950053850635514536132487
1995116587229042760067638510016192660
19963312385384403543471291966162352
1997942925180398583504399157602294
199810565039260273761350815215223148
199912290180224451562655317101962546
2000152855673414295936894091662202814
200101221663084266115423016923162476
SNOWFALL (inches) 2001 SHREVEPORT, LA (SHV)
YEARJULAUGSEPOCTNOVDECJANFEBMARAPRMAYJUNTOTAL
1972-730.00.00.00.00.00.00.6T0.00.00.00.00.6
1973-740.00.00.00.00.0T0.00.00.00.00.00.0T
1974-750.00.00.00.00.00.03.4TT0.00.00.03.4
1975-760.00.00.00.0T0.00.00.00.00.00.00.0T
1976-770.00.00.00.0T0.05.40.00.00.00.00.05.4
1977-780.00.00.00.00.00.05.92.00.30.00.00.08.2
1978-790.00.00.00.00.00.0T1.50.00.00.00.01.5
1979-800.00.00.00.0T0.00.01.4T0.00.00.01.4
1980-810.00.00.00.01.30.00.70.10.00.00.00.02.1
1981-820.00.00.00.00.0T5.6TT0.00.00.05.6
1982-830.00.00.00.00.0TTT0.00.00.00.0T
1983-840.00.00.00.00.05.4TT0.00.00.00.05.4
1984-850.00.00.00.00.00.00.44.40.00.00.00.04.8
1985-860.00.00.00.00.00.0TT0.00.00.00.0T
1986-870.00.00.00.00.0T0.0TT0.30.00.00.3
1987-880.00.00.00.00.00.01.20.80.00.00.00.02.0
1988-890.00.00.00.00.00.0TTT0.0T0.0T
1989-900.00.00.00.00.0T0.0T0.00.00.00.0T
1990-910.00.00.00.00.0T0.0T0.0TT0.0T
1991-920.00.00.00.00.00.0TTT0.00.00.0T
1992-930.00.00.0TT0.0TT1.0T0.00.01.0
1993-940.00.00.00.00.0T0.00.4TTT0.00.4
1994-950.00.00.00.0T0.0TT0.0T0.00.0T
1995-960.00.00.00.00.00.0T0.40.00.0
1996-970.00.00.00.00.00.30.1T0.0T0.00.00.4
1997-980.0T0.00.0T0.0TTT0.00.00.0T
1998-990.00.00.00.00.00.10.00.0T0.00.00.00.1
1999-000.00.00.00.00.0T1.1TTTT0.01.1
2000-010.00.00.00.0T2.2T0.00.00.0T0.02.2
2001-0.00.00.00.0TT
POR=48 YRS0.00.00.0T0.00.20.70.40.20.0T0.01.5

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2001 Shreveport, Louisiana (SHV)

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    2001 Shreveport, Louisiana (SHV)