Wednesday, January 13, 2021

2020 Annual Climate Report for Memphis, TN

2020 Annual Summary

Overall, the year 2020 featured temperatures that averaged 0.4 degrees above average, identical to 2019. However it came about with fewer extremes than the previous year. Six months averaged above normal temperatures and six below, though the warm months had greater departures from normal than the cool months, thus resulting in an above average year. 

The map above shows the departure from normal temperatures for 2020. (WeatherBell)

Precipitation-wise, the year started wet, but spring and early summer drought reversed the early excess. By December 29, precipitation was just slightly below normal, however three inches of rain to end the year resulted in a departure of +2 inches.

A NOAA map of landfalling tropical cyclones in the U.S. Three of these brought rainfall to the Mid-South - Hurricanes Laura, Delta, and Zeta.

Month-by-month recap

The year started warm and wet with temperatures that averaged over five degrees above normal and precipitation totaling almost 2.5 inches above normal. The patter favored severe weather in the pre-dawn hours on the 11th as a squall line moved through, dropping six tornadoes in the Memphis metro, the strongest an EF-2 that passed between Hernando and Olive Branch, MS. About 40,000 MLGW customers lost power due to strong wind. There were also a few snowflakes around the area on the 20th, but none recorded at Memphis International Airport. February continued the wet trend, finishing nearly 2 inches above average, but temperatures were closer to normal. There was one snow event, with up to an inch of snow falling on the night of the 6th-7th and flurries again on the 20th. Thunderstorms also occurred on five days, but there was no severe weather. 

The first quarter of 2020 ended in March the way it began - warm and wet. Temperatures averaged 4.5 degrees above normal and precipitation was more than 4 inches above normal as spring set in. From the 9th to the 24th, measurable rain occurred on 14 of the 16 days, and 20 days for the month reported rain, tying the record set in 1897. Severe weather occurred on the 28th with trees down in multiple locations across Shelby County. For the first three months of 2020, rain fell on 51 days, just missing the record of 52 set way back in 1882.

Heading into April, the weather turned cooler with temperatures averaging over 2.5 degrees below normal. It was still wet, but very near the average of 5.5 inches of rain. However, almost half of that occurred on a single day - Easter Sunday, April 12 - when severe wind damaged some trees and power lines. Severe weather also occurred on the 8th and 28th/29th, all of which were wind related. Only two April days reached 80 degrees, one less than March! May typically sees much warmer temperatures as summer approaches, and though it did warm up, Memphis still averaged more than 2 degrees below normal, with only one day that eclipsed 90 degrees. In fact, there were some late-season lows in the 40s during the second week of the month! While severe weather was limited, a destructive event on the 22nd produced widespread damaging wind in Crittenden and Shelby Counties with over 52,000 MLGW customers without power as Memorial Day weekend started.

Meteorological summer began in June with cooler than average temperatures for the third consecutive month, though not be a lot. It was also a bit drier than average, though severe weather occurred a couple of times in the first week of the month. The main event was a straight line wind system that resulted in the highest wind of the year at Memphis International - 58 mph - on the 5th. There was also some flash flooding on the 9th from slow moving storms. July was the hottest month of the year, with temperatures that averaged about 1.5 degrees above normal, in the mid 80s. In fact, the heat was persistent with only two days that failed to reach 90 degrees and low temperatures that never left the 70s the entire month. Precipitation was well below average, less than two inches for the month. Severe weather was limited. 

Finally, summer wrapped up with a break from persistent heat in August as the first week of the month averaged five degrees below normal and the month ending 1.3 degrees below average with several mornings in the 60s. Precipitation ended well above normal (12th wettest on record) with remnants of Major Hurricane Laura contributing both heavy rain and strong wind, as well as a few weak tornadoes in northeast AR on the 28th. Overall, to have two of the three summer months with below average heat was not too bad. Memphis did not reach 100 degrees in 2020.

The cooler than average trend in August was reversed for the first half of September as summer hung around, but was countered by autumn's arrival in the second half of the month. October saw multiple fronts and large temperatures swings but also ended below normal. September precipitation was hard to come by with just over an inch and a half total, though October made up for the previous month with well over four inches recorded. However, most of that fell on either the 10th, as remnants of Hurricane Delta passed through north MS, or the 28th, with remnants of Hurricane Zeta combining with a front to drop heavy rain. There was one severe weather event, on September 2nd, when scattered strong storms downed some trees and a Tornado Warning was issued as one briefly rotated on approach to the Bluff City.

The winter season began warm and dry in November. In fact, the average high temperature for the month ended up 7th warmest on record, while the average temperature for the month was in the top 10% of all Novembers on record, despite a cold snap to end the month that included snow flurries. There were only four rain days and precipitation ended up only 32% of normal with no severe weather. To end the year, December ended slightly warmer than average as a whole, but featured one of the coldest Christmas Days on record with a high of only 33 degrees. Precipitation was below average until the last two days of the year when three inches of rain fell, yielding an annual total that was two inches above average.

A month-by-month summary of average temperatures and precipitation can be found below.

Severe weather

In 2020, the Memphis office of the National Weather Service issued 286 combined Severe Thunderstorm and Tornado Warnings in their service area (221 Severe Thunderstorm and 65 Tornado). The combined number of severe weather warnings is well below the average for the past 25 years of 406. Also in 2020, there were 19 Tornado Watches and 9 Severe Thunderstorm Watches issued by the Storm Prediction Center that included some portion of the Memphis service area. The Tornado Watch count was well above the 25-year average of 11, while the Severe Thunderstorm Watch count was just below the average of 10.

The Mid-South (defined by the National Weather Service Memphis service area of eastern AR, the MO Bootheel, west TN, and north MS) recorded 33 tornadoes during 2020. There were four EF-2 tornadoes, including one in DeSoto County, and one EF-3 in Craighead County, AR, while the rest were rated EF-0 or EF-1. 

Within the eight-county Memphis metropolitan area, there were five tornado touchdowns rated EF-0 to EF-2. All five occurred in the pre-dawn hours on January 11. All but one occurred in northwest MS, including the EF-2 in DeSoto County mentioned above, and one touched down in southwest TN (Fayette County). For the year, the NWS-Memphis office received 577 severe (convective) weather reports within their service area. Below is a listing of all tornadoes that occurred in the state of TN in 2020 and severe weather reports in the greater Memphis metro.

Severe weather reports in the Memphis area in 2020

The following represents a statistical recap of the weather for 2020 in Memphis.

Memphis International Airport, Memphis, TN

Average temperature: 63.5 degrees (0.4 degrees above average)
Average high temperature: 72.5 degrees (0.0 degrees below average)
Average low temperature: 54.5 degrees (0.9 degrees above average)
Warmest temperature: 97 degrees (August 9, 10, and 11)
Coolest temperature: 21 degrees (December 25)

Heating degree days: 2599 (366 below average)
Cooling degree days: 2167 (91 below average)
Days at or above 90 degrees: 63 (1.3 days below average)
Days at or below 32 degrees: 25 (17.8 days below average)
Last freeze/first freeze: February 27-November 30 (277 day growing season)

Records set or tied: There were no monthly average temperatures that placed in the top ten warmest or coldest on record in 2020. There were also no daily warm weather records for the year, but there were three daily cold weather records set in 2020. These included:
  • January 15 (59°, record high minimum)
  • May 9 (43°, record low)
  • May 12 (57°, record low maximum)

Comments: 2020 had the exact same average temperature for the year as in 2019, which ranks both in the top 17% warmest (tied for 24th) in the 147-year historical record at Memphis. However there were fewer extremes in 2020 than the previous year. The number of days with high temperatures at or above 90 degrees was very near normal at 63. There were 25 days that fell to or below freezing, which was well below average.

Temperatures for 2020 (lows/highs) are plotted in dark blue against the normals (brown), record highs (red) and record lows (light blue).  Where the dark blue extends above or below the brown indicates temperatures above or below normal, respectively.

Annual total: 55.69" (2.01" above average)
Days with measurable precipitation: 134 (26.3 days above average)
Days with 1"+ precipitation: 17 (0.4 days below average)
Wettest day: 2.68" (October 28)

Total Snowfall: 0.6" (3.2" below average)
Days with a trace or more snowfall: 6 (3.2 above average)
Days with 1" or more snowfall: 0 (1.2 below average)
Greatest snow depth (6am CST): Trace (February 7)

Records set or tied: There were no monthly precipitation totals that placed in the top ten wettest or driest on record in 2020.  Daily records included:
  • March rain days (20, record tied)
  • October 28 (2.68" rainfall)
  • November 30 (Trace, tied snowfall)
Comments: 17 days recorded an inch or more of liquid precipitation; two days had more than 2".

Precipitation accumulation for 2020 is plotted as the dark green line, compared with a normal year in brown. 


Peak wind gust: North / 58 mph (June 5)
Average wind: 7.9 mph
Average relative humidity: 69%
Average sky cover: 55%

Click here for monthly/daily statistical recaps for Memphis International Airport.

Cirrus Weather Solutions /, Bartlett, TN

Average temperature: 61.8 degrees 
Average high temperature: 72.4 degrees 
Average low temperature: 52.4 degrees 
Warmest high temperature: 99.2 degrees (July 20th)
Warmest low temperature: 77.5 degrees (June 28)
Coolest high temperature: 28.4 degrees (January 20)
Coolest low temperature: 20.2 degrees (December 25)
Comments: None

Annual total: 55.68" (automated rain gauge), 59.16"(manual CoCoRaHS rain gauge) 
Days with measurable precipitation: 141
Wettest date: 2.69" (April 12) (via automated gauge) 
Snowfall: 1.0 inch
Comments: One inch of snow fell on February 6-7. Traces occurred on January 20, February 20, November 30, and December 15.

Peak wind: Northwest/52 mph (May 22)
Average relative humidity: 78% 
Average barometric pressure: 30.03 in. Hg
Comments: None

Click here for a daily statistical recap for Bartlett, TN.

MWN Forecast Accuracy

Number of MWN forecasts produced and verified in 2020: 514
MWN average temperature error: 2.11 degrees
MWN forecast temperatures within 2 degrees of actual: 67%
MWN average dewpoint error: 2.20 degrees
MWN forecast dewpoints within 2 degrees of actual: 67%

MWN's forecasts extend out five periods (2.5 days, or roughly 60 hours) and the numbers above represent the error/accuracy of the entire 2.5 day period. Historical accuracy statistics can be found here.

Erik Proseus
MWN Meteorologist

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MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder

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