July is finally here and nothing reminds us of the dog days of summer more than the persistent heat and humidity. Not a fan of the summer heat? Don’t worry, not every day will welcome us with this summertime tradition. In fact, the overall pattern for July is looking a bit cooler than average this year.
The Climate Prediction Center (part of the National Oceanic & Atmospheric Administration, or NOAA) issued its forecast for July 2021 last week. While the pattern in the western U.S. and northeastern states favors a warmer July than average, NW Arkansas and the River Valley actually favor a cooler July this year.
Multiple days of rain last month have increased the soil moisture to above-average levels across the region. More frequent cloud cover and frontal activity in the region is also helping to keep temperatures a bit cooler than normal.
Forecast models and known weather pattern signals around the globe (called teleconnections) favor a more soggy pattern in the southern U.S. compared to the north.
The highest chance for above-average rainfall this month is located in parts of Arizona and New Mexico, along with the central Gulf Coast and Lower Mississippi River Valley.
The above-average precipitation forecast also helps explain why NW Arkansas and the River Valley are more likely to be cooler than average this month. Ever notice our hottest temperatures occur mainly on sunny days? More rain means more cloud cover and this can help prevent temperatures throughout the day from increasing very quickly.
July Monthly Preview
July is pretty uneventful in NW Arkansas in terms of averages changing. We will reach an average daily high of 90°F at the end of the month. However, this is only a few degrees warmer than the start of July. At night, our average low-temperature increases by 1°F.
With the Summer Solstice behind us, July is the first month we see a net loss of daylight. A total of 35 minutes will be lost between July 1 and July 31. Each month will continue to see a loss of daylight until the Winter Solstice in December.
Summertime afternoon pop-up showers or thunderstorms are nothing new for NW Arkansas in July. The spotty nature of them and the northward movement of the jetstream to the Northern Plains this month lowers our average monthly rainfall to 3.80″ in Fayetteville.
Similar to NW Arkansas, the River Valley doesn’t see much change in average temperatures throughout July. Our average high in Fort Smith will increase to 95°F by the end of the month and the average low will go up by 1°F to 72°F.
In terms of daylight, our sunrise will be 20 minutes later with sunset occurring 14 minutes earlier by the end of the month. This will result in a 34 minute total loss of daylight throughout the month.
The River Valley typically sees a decrease in rainfall during July compared to June. June’s average monthly rainfall in Fort Smith is 4.56 and July decreases to 3.39″.
Keep in mind, this is an overall look at the pattern for July 2021. The daily/weekly variations in the forecast may not follow the outlooks exactly. Be sure to stay up to date with your Weather Authority team on all the forecast details on-air, online, and on social media!