Daily records
Page built 2026-10-15
Data as of 2025-12-31
Search
Built 2026-10-15 (15 October 2026)

Mermentau Weather Records (USC00166142)

Record envelope, standing records and threshold days for Mermentau (USC00166142), Louisiana, United States, with 46 years of record.

Key Facts for Mermentau

  • Mermentau (USC00166142) is a weather station in Louisiana, United States at 30.19 latitude and -92.59 longitude, 5 m (16 ft) above sea level.
  • The station reports from 1943 to 1988, 46 years of record.
  • 0 records set at Mermentau still stand.
  • Records are tracked for prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Mermentau set a daily record precipitation of 75.7 mm (3.0 in) on 2 April 1988.

About the Station

  • Location: Louisiana, United States, 30.19 latitude, -92.59 longitude.
  • Elevation: 5 m (16 ft).
  • Period of record: 1943 to 1988, 46 years.
  • Eligible elements: prcp, snow, snwd.

Daily Record Envelope and 2026

0 days at or beyond a record
Daily record high and record low at Mermentau, with 2026 drawn through them The band shows the record high and record low for each calendar day at Mermentau. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. 000111 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Mermentau. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Mermentau, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jann/an/an/an/a
Febn/an/an/an/a
Marn/an/an/an/a
Aprn/an/an/an/a
Mayn/an/an/an/a
Junn/an/an/an/a
Juln/an/an/an/a
Augn/an/an/an/a
Sepn/an/an/an/a
Octn/an/an/an/a
Novn/an/an/an/a
Decn/an/an/an/a

Which Years Hold Standing Records

0 standing records
Standing records at Mermentau by the year they were set 0 records at Mermentau still stand. 00000000000
0 records at Mermentau still stand.
Standing records at Mermentau by the year they were set
Year setStanding records

All-Time Record Progression

1 new records
When Mermentau set new all-time records 1 all-time records were set at Mermentau between 16 May 1980 and 16 May 1980. Each dot is a new record. Record daily precipitation16 May 1980: Record daily precipitation 398.0 mm (15.7 in)1980
1 all-time records were set at Mermentau between 16 May 1980 and 16 May 1980. Each dot is a new record.
When Mermentau set new all-time records
DateKindDetail
1980-05-16Record daily precipitationRecord daily precipitation 398.0 mm (15.7 in)

Wettest Day of Each Month

May: 398.0 mm (15.7 in)
Record daily precipitation for each month at Mermentau The wettest day on record for each calendar month at Mermentau. The most was 398.0 mm (15.7 in) on 16 May 1980. 0100200300400 Jan: 127.0 mm (5.0 in), 6 January 1950 Jan Feb: 139.7 mm (5.5 in), 5 February 1955 Feb Mar: 127.0 mm (5.0 in), 1 March 1965 Mar Apr: 307.3 mm (12.1 in), 14 April 1967 Apr May: 398.0 mm (15.7 in), 16 May 1980 May Jun: 199.4 mm (7.9 in), 28 June 1957 Jun Jul: 149.9 mm (5.9 in), 6 July 1946 Jul Aug: 165.4 mm (6.5 in), 29 August 1978 Aug Sep: 182.6 mm (7.2 in), 20 September 1983 Sep Oct: 242.8 mm (9.6 in), 29 October 1974 Oct Nov: 152.4 mm (6.0 in), 8 November 1943 Nov Dec: 251.7 mm (9.9 in), 6 December 1971 Dec
The wettest day on record for each calendar month at Mermentau. The most was 398.0 mm (15.7 in) on 16 May 1980.
Record daily precipitation for each month at Mermentau
MonthRecord daily precipitation (mm)Date
Jan127.0 mm (5.0 in)6 January 1950
Feb139.7 mm (5.5 in)5 February 1955
Mar127.0 mm (5.0 in)1 March 1965
Apr307.3 mm (12.1 in)14 April 1967
May398.0 mm (15.7 in)16 May 1980
Jun199.4 mm (7.9 in)28 June 1957
Jul149.9 mm (5.9 in)6 July 1946
Aug165.4 mm (6.5 in)29 August 1978
Sep182.6 mm (7.2 in)20 September 1983
Oct242.8 mm (9.6 in)29 October 1974
Nov152.4 mm (6.0 in)8 November 1943
Dec251.7 mm (9.9 in)6 December 1971

Latest Records

20
Latest records at Mermentau
DateStationRecordValueBeat old record byOld record stoodSignificance
2 April 1988Mermentau, USdaily rain75.7 mm (3.0 in)27.9 mm (1.1 in)43 years24 of 100 (Routine)
9 March 1988Mermentau, USdaily rain55.9 mm (2.2 in)11.7 mm (0.5 in)12 years13 of 100 (Routine)
7 January 1988Mermentau, USdaily rain36.3 mm (1.4 in)3.3 mm (0.13 in)42 years17 of 100 (Routine)
17 November 1987Mermentau, USdaily rain54.4 mm (2.1 in)11.5 mm (0.5 in)4 years11 of 100 (Routine)
10 August 1987Mermentau, USdaily rain53.8 mm (2.1 in)18.2 mm (0.7 in)29 years21 of 100 (Routine)
8 July 1987Mermentau, USdaily rain35.3 mm (1.4 in)19.6 mm (0.8 in)24 years22 of 100 (Routine)
25 June 1987Mermentau, USdaily rain49.8 mm (2.0 in)12.2 mm (0.5 in)24 years17 of 100 (Routine)
25 May 1987Mermentau, USdaily rain59.7 mm (2.4 in)35.6 mm (1.4 in)40 years26 of 100 (Routine)
26 February 1987Mermentau, USdaily rain30.2 mm (1.2 in)6.1 mm (0.24 in)16 years11 of 100 (Routine)
22 January 1987Mermentau, USdaily rain (Tie)33.0 mm (1.3 in)tie17 years2 of 100 (Routine)
18 January 1987Mermentau, USdaily rain54.1 mm (2.1 in)5.8 mm (0.23 in)24 years14 of 100 (Routine)
4 January 1987Mermentau, USdaily rain36.1 mm (1.4 in)12.5 mm (0.5 in)23 years16 of 100 (Routine)
23 December 1986Mermentau, USdaily rain63.5 mm (2.5 in)2.5 mm (0.10 in)29 years13 of 100 (Routine)
16 December 1986Mermentau, USdaily rain50.0 mm (2.0 in)18.2 mm (0.7 in)27 years20 of 100 (Routine)
25 November 1986Mermentau, USdaily rain61.5 mm (2.4 in)33.3 mm (1.3 in)13 years25 of 100 (Routine)
24 November 1986Mermentau, USdaily rain72.4 mm (2.9 in)55.9 mm (2.2 in)28 years42 of 100 (Notable)
5 November 1986Mermentau, USdaily rain55.9 mm (2.2 in)22.1 mm (0.9 in)20 years21 of 100 (Routine)
9 October 1986Mermentau, USdaily rain22.1 mm (0.9 in)11.9 mm (0.5 in)4 years9 of 100 (Routine)
24 July 1986Mermentau, USdaily rain45.2 mm (1.8 in)13.4 mm (0.5 in)36 years22 of 100 (Routine)
26 May 1986Mermentau, USdaily rain61.2 mm (2.4 in)28.2 mm (1.1 in)27 years20 of 100 (Routine)

Extremes by Year

1943 to 1988
Yearly extremes at Mermentau: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Wettest day (Rx1day)398.0 mm (15.7 in)1980121.9 mm (4.8 in)46
Wettest five days (Rx5day)495.5 mm (19.5 in)1980174.6 mm (6.9 in)46
Longest dry spell (CDD)51 days195322 days46

Wettest day (Rx1day)

Wettest day (Rx1day) at Mermentau by year The wettest day of the year at Mermentau, 1943 to 1988. The record is 398.0 mm (15.7 in) in 1980, marked on the chart; the median year is 121.9 mm (4.8 in). 01002003004001950196019701980Record: 398.0 mm (15.7 in) in 1980
The wettest day of the year at Mermentau, 1943 to 1988. The record is 398.0 mm (15.7 in) in 1980, marked on the chart; the median year is 121.9 mm (4.8 in).
Wettest day (Rx1day) at Mermentau by year
YearWettest day (Rx1day)
1943152.4 mm (6.0 in)
194488.4 mm (3.5 in)
194582.6 mm (3.3 in)
1946149.9 mm (5.9 in)
1947129.5 mm (5.1 in)
194869.9 mm (2.8 in)
194981.3 mm (3.2 in)
1950127.0 mm (5.0 in)
195158.4 mm (2.3 in)
1952115.6 mm (4.6 in)
1953260.4 mm (10.3 in)
195444.5 mm (1.8 in)
1955139.7 mm (5.5 in)
1956110.0 mm (4.3 in)
1957199.4 mm (7.9 in)
195874.9 mm (2.9 in)
1959125.7 mm (4.9 in)
196068.6 mm (2.7 in)
1961101.6 mm (4.0 in)
1962129.5 mm (5.1 in)
196373.7 mm (2.9 in)
1964133.4 mm (5.3 in)
1965127.0 mm (5.0 in)
196685.1 mm (3.4 in)
1967307.3 mm (12.1 in)
1968116.8 mm (4.6 in)
1969207.8 mm (8.2 in)
197084.6 mm (3.3 in)
1971251.7 mm (9.9 in)
1972118.1 mm (4.6 in)
1973158.2 mm (6.2 in)
1974242.8 mm (9.6 in)
1975104.1 mm (4.1 in)
197680.0 mm (3.1 in)
1977144.5 mm (5.7 in)
1978165.4 mm (6.5 in)
197999.1 mm (3.9 in)
1980398.0 mm (15.7 in)
1981116.8 mm (4.6 in)
1982154.9 mm (6.1 in)
1983182.6 mm (7.2 in)
1984143.5 mm (5.6 in)
1985142.2 mm (5.6 in)
198672.4 mm (2.9 in)
198759.7 mm (2.4 in)
198875.7 mm (3.0 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Mermentau by year The wettest five days of the year at Mermentau, 1943 to 1988. The record is 495.5 mm (19.5 in) in 1980, marked on the chart; the median year is 174.6 mm (6.9 in). 02004006001950196019701980Record: 495.5 mm (19.5 in) in 1980
The wettest five days of the year at Mermentau, 1943 to 1988. The record is 495.5 mm (19.5 in) in 1980, marked on the chart; the median year is 174.6 mm (6.9 in).
Wettest five days (Rx5day) at Mermentau by year
YearWettest five days (Rx5day)
1943304.7 mm (12.0 in)
194494.0 mm (3.7 in)
1945143.9 mm (5.7 in)
1946191.8 mm (7.6 in)
1947172.7 mm (6.8 in)
194879.1 mm (3.1 in)
1949159.3 mm (6.3 in)
1950147.3 mm (5.8 in)
195185.8 mm (3.4 in)
1952134.2 mm (5.3 in)
1953435.7 mm (17.2 in)
195464.8 mm (2.6 in)
1955260.9 mm (10.3 in)
1956176.4 mm (6.9 in)
1957260.4 mm (10.3 in)
1958152.3 mm (6.0 in)
1959205.7 mm (8.1 in)
1960111.0 mm (4.4 in)
1961159.0 mm (6.3 in)
1962188.0 mm (7.4 in)
1963164.9 mm (6.5 in)
1964202.7 mm (8.0 in)
1965143.5 mm (5.6 in)
1966172.2 mm (6.8 in)
1967402.5 mm (15.8 in)
1968148.1 mm (5.8 in)
1969279.4 mm (11.0 in)
1970110.0 mm (4.3 in)
1971316.5 mm (12.5 in)
1972184.1 mm (7.2 in)
1973274.3 mm (10.8 in)
1974243.1 mm (9.6 in)
1975198.8 mm (7.8 in)
1976103.4 mm (4.1 in)
1977277.4 mm (10.9 in)
1978180.6 mm (7.1 in)
1979163.6 mm (6.4 in)
1980495.5 mm (19.5 in)
1981166.6 mm (6.6 in)
1982258.4 mm (10.2 in)
1983209.3 mm (8.2 in)
1984184.9 mm (7.3 in)
1985297.9 mm (11.7 in)
1986145.1 mm (5.7 in)
1987110.2 mm (4.3 in)
1988131.6 mm (5.2 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Mermentau by year The longest dry spell of the year at Mermentau, 1943 to 1988. The record is 51 days in 1953, marked on the chart; the median year is 22 days. 1020304050601950196019701980Record: 51 days in 1953
The longest dry spell of the year at Mermentau, 1943 to 1988. The record is 51 days in 1953, marked on the chart; the median year is 22 days.
Longest dry spell (CDD) at Mermentau by year
YearLongest dry spell (CDD)
194325 days
194427 days
194518 days
194619 days
194722 days
194825 days
194921 days
195018 days
195127 days
195229 days
195351 days
195423 days
195538 days
195618 days
195718 days
195827 days
195919 days
196022 days
196127 days
196218 days
196343 days
196422 days
196524 days
196614 days
196732 days
196817 days
196921 days
197020 days
197123 days
197230 days
197321 days
197419 days
197528 days
197616 days
197722 days
197846 days
197931 days
198031 days
198122 days
198221 days
198319 days
198418 days
198518 days
198622 days
198730 days
198814 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Rainfall Return Levels

43 years, 1943 to 1987

A day with at least 118.5 mm (4.7 in) of rain is expected about once in 2 years. A day with at least 411.6 mm (16.2 in) of rain is expected about once in 100 years.

Rainfall return levels at Mermentau: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years118.5 mm (4.7 in)
5 years177.3 mm (7.0 in)
10 years223.1 mm (8.8 in)
25 years290.1 mm (11.4 in)
50 years347.4 mm (13.7 in)Longer than the 43 years of record
100 years411.6 mm (16.2 in)Longer than the 43 years of record

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 43 years of values from 1943 to 1987.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 398.0 mm (15.7 in) in 1980; 307.3 mm (12.1 in) in 1967; 260.4 mm (10.3 in) in 1953.

Download the Data

  • Data for Mermentau standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Mermentau threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of . Last revised (2025-12-31).