Sunday, September 19, 2021

Who's ready for fall? Autumn front arrives Tuesday PM

In the wake of the now-dissipated remnants of Nicholas, a tropical-like airmass sits over the Lower Mississippi Valley into the southeastern U.S. that has led to daily showers, some heavy, and a few thunderstorms each of the past few days. This pattern will stick around another day before the first significant fall cold front arrives just in time for the autumnal equinox! Let's hit a few details...


The start of the work week brings more rain chances, though they appear to be a bit lower than the past few days. Scattered showers and thunderstorms are possible throughout the area during the day, but appear to be most likely east of the Mississippi River. With warm, and muggy air around, and fewer showers than past days, temperatures will rebound into the mid 80s with partly sunny skies in the afternoon. A south wind keeps dewpoints in the lower 70s - which is where they have been the past week.

The HRRR model forecast radar for Monday shows most precipitation remaining east of the metro. Remember, models aren't gospel and we think there could be some scattered activity further to the west, but it won't be as wet as the past few days. (WeatherBell)


Cold front day! We'll start the day with warm and muggy conditions, but it won't take long before the wind shift associated with the front arrives around mid-day. That will trigger scattered showers and thunderstorms once again, with fairly high rain chances lingering into the afternoon and evening. Highs will again reach the mid 80s, and could begin falling by mid-afternoon. Overall, rain amounts Monday and Tuesday are likely to average in the 0.5"-1.0" range with locally higher amounts where multiple heavy showers or storms move over. Drier air associated with the front won't get here until Tuesday night, with a push of cooler air arriving on gusty north wind. 

The effects of the fall front can be seen in this forecast of dewpoints on Tuesday. Humid air will be shoved away by north wind that brings much more comfortable conditions. (WeatherBell)

This loop shows total atmospheric moisture from Monday evening through Friday and also clearly shows the arrival of drier air behind the front. Very moist air (yellows to reds) is displaced by the dry air (in purple to brown) behind the front. (WeatherBell)


Fall officially starts at 2:20pm Wednesday and it'll certainly feel like the seasons have changed! We'll wake up to temperatures near 60 degrees. Despite sunshine all day, high temperatures will only reach the mid 70s on a dry north breeze. With that dry air in place, dewpoints will fall into the 40s (FORTIES)! That is dry enough to break out the hand lotion. Thursday and Friday will feature abundant sunshine, morning lows in the 50-55 degree range and afternoon highs in the mid to upper 70s. A simply stunning end to the week and welcome change!

First weekend of fall

...will feel like it! Another front may graze the area Saturday, but with no more than a few clouds. It will keep things dry throughout the weekend and into early the following week. While temperatures will start to slowly rebound to near average levels, lows will still be in the 50s to near 60 and highs in the lower 80s. With dewpoints remaining low, it will be a comfortable 80 degrees in the afternoons. Should be beautiful weather for football Friday night and Saturday afternoon at the Liberty Bowl. After Tuesday, no rain is in the forecast for a week. Enjoy!

The temperature outlook from the Climate Prediction Center for the end of September indicates a good chance of below average temperatures. (NOAA/CPC)

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

Sunday, September 12, 2021

Humidity & rain chances return as T.S. Nicholas moves towards southeast TX

Much to my chagrin, and probably most of yours, the cooler mornings and below average humidity of this past week is on its way out for the coming week. High pressure to our east brings a return of near-70° dewpoints on light southerly flow, as well as an increase in shower and thunderstorm chances for the coming week. Let's dive into the details.


With wind shifting to the south today, moisture is starting to increase again after a very pleasant week gone by. Dewpoints - which were in the 50s for much of the past week - will rise to the upper 60s to near 70 degrees to start the week. Ick. Moisture aloft also increases, and that means more scattered to broken cloud cover, especially during the daytime hours. While most of us stay dry, I expect to see a few echoes on radar by Monday afternoon as instability rises a bit. Tuesday will features a few more showers than Monday, but rain chances are still likely to only be 10-20% each day. High temperatures will be in the upper 80s Monday and mid 80s Tuesday with lows in the low 70s instead of the 50s and 60s of the past several days. You'll notice that as you step out in the mornings.


As a front moves south towards the region but stalls near the KY/TN border, atmospheric moisture increase continues into mid-week, mainly sourced to our south where brand-new Tropical Storm Nicholas (currently making its way towards the TX coast; see below) will likely be in the vicinity of eastern TX. Southerly wind will push clouds and increased rain chances into the area, though with the main focus of the storm well to our south, I don't expect rain-outs locally. We'll put POPs (probability of precipitation) in the "scattered" range, or 40-50%. Rainfall totals will be insufficient to completely overcome the recent dryness, likely less than an inch in any one spot.

Additional cloud cover will hold highs back to the mid 80s with morning lows near or just above 70° and dewpoints lingering around 70° as well. It'll feel fairly sticky and you'll want to keep the umbrella handy. Forecast confidence dips just a bit for this mid-week period, depending on the eventual track of Nicholas, though it's likely to remain well to our south.

Friday into next weekend

Remnants of Nicholas may dry up a bit to our south due to a lack of flow to push it somewhere else. Meanwhile, high pressure rebuilds a bit over our area, so the Mid-South will probably see diminishing rain chances into next weekend, though maybe not totally dry. High temperatures start to rise back to near 90 degrees with humidity sticking around without a frontal system to shove it away. Overall, for the last weekend of "official summer," you'll probably be ready for fall to arrive for good. We're not quite there yet! 

The temperature outlook from the Climate Prediction Center for next weekend into the start of the following week paints a warm picture. There is a very high probability of above average temperatures for our area, during a time when average highs are in the mid 80s. 

If you are heading to the Mississippi State/Memphis football game on Saturday, it won't be hot chocolate or long sleeve weather yet - plan on a bit of sweat, even just as "engaged bystanders" in the stadium!

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

Monday, September 6, 2021

August 2021 Climate Report for Memphis, TN

August Climate Recap

With summer finally arriving in mid-July, it was not likely to let up heading into the hottest month of the year - and it did not. Twenty of thirty days reached 90 degrees and the average temperature for the month ended about a degree above normal. That above average temperature was driven entirely by overnight lows however. The average high of 91.5 was right at normal, while overnight lows averaged two degrees above normal. including one record high minimum temperature on the 26th (79 degrees).

A dry trend that started as the heat built in late July extended through August with less than 2.5 inches of rain falling for the month at the airport and even less (by about an inch) in Bartlett. The wettest day of the month at the airport, the 13th, was also the only day of measurable rainfall in the first two and a half weeks of August. Rain days became more common the last two weeks. That wet day also had the only report of severe weather for the month. Localized heavy rainfall of multiple inches fell in the afternoon resulting in flooding that stalled vehicles in East Memphis along Poplar Avenue. There were no Severe Thunderstorm Warnings issued in the metro in August.

Memphis International Airport, Memphis, TN

Average temperature: 83.0 degrees (0.9 degrees above average) 
Average high temperature: 91.5 degrees (0.0 degrees below average) 
Average low temperature: 74.5 degrees (1.9 degrees below average) 
Warmest temperature: 96 degrees (24th, 25th, 26th) 
Coolest temperature: 68 degrees (4th, 5th) 
Heating Degrees Days: 0 (0 above average)
Cooling Degree Days: 566 (38 above average) 
Records set or tied: Record high minimum (26th, 79 degrees)
Comments: There were 20 days with high temperatures above 90 degrees, which is average for July.

Monthly total: 2.40" (0.97" below average) 
Days with measurable precipitation: 5 (2.6 days below average) 
Wettest 24-hour period: 1.05" (13th) 
Snowfall: 0.0"
Records set or tied: None
Comments: Two days recorded precipitation of more than an one-half inch, while July averages 2.3 days.

Peak wind: East/38 mph (13th) 
Average wind: 7.2 mph 
Average relative humidity: 69% 
Average sky cover: 50% 

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

Cirrus Weather Solutions /, Bartlett, TN

Average temperature: 80.3 degrees 
Average high temperature: 91.4 degrees 
Average low temperature: 71.8 degrees 
Warmest temperature: 98.4 degrees (11th) 
Coolest temperature: 62.1 degrees (5th) 
Comments: None 

Monthly total: 1.43" (automated rain gauge), 1.60"(manual CoCoRaHS rain gauge) 
Days with measurable precipitation: 6
Wettest date: 0.58" (19th) (via automated gauge) 
Snowfall: 0.0"
Comments: None

Peak wind: North/23 mph (31st)
Average relative humidity: 80% 
Average barometric pressure: 29.97in. Hg
Comments: None

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

MWN Forecast Accuracy

MWN average temperature error: 1.53 degrees 
MWN forecast temperatures within 2 degrees of actual: 84% 
MWN average dewpoint error: 1.45 degrees 
MWN forecast dewpoints within 2 degrees of actual: 82% 

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

Climate Outlook - September 2021

The September climate outlook for the United States from the Climate Prediction Center is shown below. Above average temperatures are forecast for the western states, New England, and the Florida peninsula. Slightly below average temperatures are forecast in the Lower Mississippi and Tennessee River Valleys. Odds favor very near average temperatures for Memphis with a 34% chance of below average temperatures and a 33% chance of above average conditions. The average temperature for September is 76.0 degrees, about six degrees below the August average.

Precipitation is expected to be well above normal for the Mid-Atlantic states into southern New England with wetter than average conditions extending south into the southeast U.S. Additional above average precipitation is forecast for the Desert Southwest. Below average precipitation is forecast for the Pacific Northwest. For Memphis, odds are slightly in favor of above average precipitation (37%) versus a 30% chance of below average precipitation. Rainfall historically averages only 3.03 inches.

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

Sunday, September 5, 2021

Pleasant Labor Day weather leads to a sunny week with low humidity

The early signs of fall are on the way for the Mid-South! Drier and more comfortable temps are in the forecast for this week, with quiet weather to accompany it. After a comfortable Memorial Day and 4th of July, Labor Day looks to be absolutely beautiful as well, continuing the trend of nice holidays this summer! Skies will be sunny, with a pleasant breeze out of the northeast. The best part? The air will be dry, so it will feel even better outside! Highs will be in the mid to upper 80s. For Monday night, skies will remain clear, and temperatures will drop to refreshing levels. 

Early week

By the time we wake up Tuesday, we’ll be in the low 60s with clear skies. Tuesday and Wednesday look very similar; sunny with low humidity, but a bit warmer with a high in the upper 80s to near 90 degrees. Lows should be in the mid 60s, with dry air remaining in place. Wednesday night we get a little “boost” to the comfortable feel to the air, after another cold front will move through the Mid-South. This will be a dry front, but it will help to reinforce the dry air and knock temperatures back a bit once again. Lows Wednesday night should drop into the low 60s, with clear skies sticking around. 

A mid-week cold front will reinforce the low humidity we have early in the week, bringing a taste of fall! The European model depiction of dewpoints Wednesday evening is shown. (WeatherBell)

Late week

Thursday looks like a stunning “Chamber of Commerce” type day across the metro, with very low humidity, temperatures in the low to mid 80s, and sunny skies. Thursday night looks to be the coolest of the week as well, with lows dropping to near 60 degrees, with a few upper 50s not out of the question, especially in outlying suburbs/rural areas!

Dry weather continues into Friday, with temps slowly beginning to rebound to more seasonal levels. Friday should still be quite nice, with a high in the upper 80s. The 90s return by next weekend, and it’s looking like a perfect weekend to have a last hoorah at the pool. Humidity will slowly be returning, but overall the weekend should be pretty nice!

Peaking at the tropics

As far as the tropics go, Hurricane Larry is spinning away in the central Atlantic Ocean as a large major hurricane, and should continue to do so for the entire week without threatening land. Always nice to enjoy a beautiful storm on satellite that doesn’t have any major land impacts!

Satellite loop of Hurricane Larry on Sunday evening, showing its very large 70+ mile wide eye!
National Hurricane Center forecast track for Hurricane Larry, showing it remaining a hurricane all week and recurving well off the U.S. east coast.

Closer to home, there is a low-end chance that a weak tropical system develops in the northern Gulf as the week goes on. For now, it’s looking like it would be pushed well east of our area, and looks to remain weak. Beyond that, no immediate threats on the horizon. However, we are in the peak of hurricane season and even though we are well inland, tropical cyclones can still bring major impacts to the area. Of course, we’ll be closely watching the tropics and will keep you updated if anything threatens! For now, enjoy a nice calm week of weather and be sure to wear lots of sunscreen!

The Tropical Weather Outlook from NHC shows a 30% chance of development in the northern Gulf of Mexico later in the week. 

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