Wednesday, October 9, 2019

September 2019 Climate Data for Memphis, TN

September Climate Recap

Temperatures usually start receding in September as summer gives way to early fall. That was not the case this year though, as September ended up as the hottest on record and a degree warmer on average than August. Only two days failed to reach 90 degrees and the coolest night was a balmy 68 degrees, resulting in an average temperature for the month that was more than 8 degrees above normal. The warmth was prevalent across much of the eastern three-fourths of the nation.

Average temperature anomalies for the U.S. in September show a hot month for most locations east of the Rocky Mountains, while cool weather covered areas west of the Rockies. (NWS data via WeatherBell)

What had been a wet year to this point "self-corrected" to an extent in September with one of the driest months in recent history. In fact, with just over one-tenth of an inch of rain, it was the third driest September on record! Coupled with the record heat, drought conditions quickly developed with a classification of "moderate" for parts of the metro (see below). Measurable rain only fell on two days in September at the airport. There was no severe weather in September.

Memphis International Airport, Memphis, TN

Average temperature: 83.5 degrees (8.3 degrees above average)
Average high temperature: 93.7 degrees (8.6 degrees above average)
Average low temperature: 73.3 degrees (8.1 degrees above average)
Warmest temperature: 100 degrees (16th)
Coolest temperature: 68 degrees (24th)
Heating Degrees Days: 0 (11 below average)
Cooling Degree Days: 564 (248 above  average)
Records set or tied: Hottest September on record. Daily record high temperatures set on the 17th (99) and 18th (99), and tied on the 27th (95).
Comments: 28 days recorded a high temperature of 90 degrees or warmer, 7.7 days more than the average for the month and a September record.

Monthly total: 0.12" (2.97" below average)
Days with measurable precipitation: 2 (5.3 days below average)
Wettest 24-hour period: 0.10" (23rd)
Snowfall: None
Records set or tied: None
Comments: The month was the 3rd driest September on record in Memphis.

Peak wind: West/58 mph (13th)
Average wind: 5.4 mph
Average relative humidity: 73%
Average sky cover: 50%

Click here for a daily statistical recap for Memphis International Airport.

Cirrus Weather Solutions /, Bartlett, TN

Average temperature: 80.6 degrees
Average high temperature: 95.0 degrees
Average low temperature: 68.5 degrees
Warmest temperature: 100.1 degrees (16th)
Coolest temperature: 64.0 degrees (6th)
Comments: Temperature data was only recorded through the 23rd of the month due to station relocation.

Monthly total: 0.22" (automated rain gauge), 0.26" (manual CoCoRaHS rain gauge)
Days with measurable precipitation: 2
Wettest date: 0.15" (23rd) (via automated gauge)
Snowfall: None
Comments: Precipitation data was available for the entirety of the month of September.

Peak wind: South/18 mph (20th)
Average relative humidity: 74%
Average barometric pressure: 30.06 in. Hg
Comments: The above data was only recorded through the 23rd of the month due to station relocation.

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

MWN Forecast Accuracy

MWN average temperature error: 1.61 degrees
MWN forecast temperatures within 2 degrees of actual: 76%
MWN average dewpoint error: 1.95 degrees
MWN forecast dewpoints within 2 degrees of actual: 72%

MWN's forecasts extend out five periods (2.5 days, or roughly 60 hours). Historical accuracy statistics can be found here.

Climate Outlook - October

The October climate outlook for the United State from the Climate Prediction Center is shown below. Below average temperatures are expected across the Pacific Northwest and Northern Rockies. Above normal temperatures are likely to be found in the southern and eastern U.S., most pronounced in the southeast. Odds favor above average temperatures for Memphis in October. Memphis averages 64.1 degrees for the month, or about ten degrees cooler than September.

A wet October is forecast for the northern tier of the country, particularly the Midwest and Upper Mississippi Valley. Drier than average conditions are forecast across the southeast U.S. For Memphis, odds favor slightly below average rainfall, which historically results in right at four inches in October.

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

Sunday, September 29, 2019

More hot weather... but a (relative) end is in sight!

Two weeks ago in this space, we asked the same question and didn't get an appropriate answer: "when will the heat finally end?" This time we ask with more desperation and urgency!

Never-ending summer brings record heat and drought

 Summer 2019, though it started a little late, seems to never want to end! Relative to normal, September has been particularly brutal, ranking warmest on record and top 3 driest through the 28th.

In addition to the heat, moderate drought conditions have developed rather quickly the past couple of weeks for parts of the metro, according to the U.S. Drought Monitor.

The U.S. Drought Monitor indicates a large portion of TN is now in "Moderate Drought" conditions, including much of the TN portion of the Memphis metro.

The lack of precipitation this month has brought the drought conditions, but also contributed to the record high temperatures due to dry ground, despite increasingly lower sun angles as we head into fall. Officially, just over 0.10" of precipitation has occurred this month, which ranks third driest on record, with no more projected until at least the end of the week.

As we head into the final days of the month and the calendar turns to Halloween month, record high remains in the forecast and 90s are growing supremely tiresome.

So, when does it end?

A few more days of heat

Unfortunately, we'll have to get through another few days of likely record-breaking heat as mid-summer high pressure bakes the parched southeast U.S. We will probably tie or break a couple of daily record highs, and the all-time October high temperature of 95° will get threatened Tuesday and Wednesday. In fact, I have high confidence that we'll set a new monthly record this week.

Normal and record maximum temperatures for the first week of November in Memphis. The all-time record high for October is 95°, which could be broken this week.

By Thursday, the high will start to lose its influence a bit as a strong trough (that has brought winter weather to the northern Rockies this weekend!) shifts east while weakening. That shifting trough should push a cold front into the Mid-South Thursday night or Friday, which should take the top layer off our heat cake as we head into next weekend. Look for temperatures to drop about 10 degrees by Friday into the weekend, with highs in the mid 80s or so. While still above normal (which by the end of the week will be around 80), it will be a welcome shift in the right direction. Rainfall will likely be limited with the front.

A pronounced ridge of high pressure at the mid levels (18,000 feet) dominates the eastern U.S., while a strong trough dominates the west to start the week. By week's end, the ridge flattens (weakens) as the trough pushes over the top of it, resulting in a reduction of the record heat in our area by week's end. Colors are based on the amount of anomaly present in the pressure pattern. (European model via WxBell)

As we head later into the weekend, or early the following week, models are hinting at reinforcements arriving. That could bring higher rain chances and additional likely put a cap on any additional "re-warming." I expect this week will be the last string of ninety degrees days we will see this year.

#TeamMWN staff changes

Over the past couple of weeks, we've had a series of changes in the "intern department" with #TeamMWN. Recall these Mississippi State University meteorology students are the ones that keep our social media channels updated and do occasional blogging and forecasting. I am eternally grateful for the work that the "retiring" interns have done and look forward to the new students showcasing their skills and talents over the coming months.

Those who have departed recently include Ethan Black, who is now a mathematics major at MSU, and Jennifer Lambers, who has just started her first broadcast meteorologist position at WALA FOX10 in Mobile, AL! Congratulations!

Our new interns include:

  • Paige Davide - a first-year Meteorology graduate student
  • Max Magness - a first-year Meteorology graduate student
  • Alexa Santa - a sophomore majoring in Meteorology

Each will bring their own "flavor" to the social media feeds, while serving to keep all of you informed on the latest trends in Memphis and Mid-South weather. (I'm lowering the hammer though if they cannot collectively figure out how to push the summer heat out of here!) In addition, spring addition Caroline Sleeper remains on the team as our "senior-most" intern. She is a Junior in Meteorology at MSU. On their behalf, I say #HailState and Go Bulldogs!

Erik Proseus
MWN Meteorologist

Follow MWN on Facebook and Twitter for routine updates and the latest info!
Complete MWN Forecast: on the mobile web or via the MWN mobile app
Download our iPhone or Android apps, featuring StormWatch+ severe weather alerts!
MWN is a NOAA Weather Ready Nation Ambassador Meteorologist Erik Proseus is an NWA Digital Seal Holder