The Switch Will Flip

KEY MESSAGES

Updated at 1218 PM CDT Mon Sep 28 2026

- Warming well above normal by midweek with highs reaching the 80s to lower 90s.

- Low to medium shower chances develop by Friday, then increasing rain chances this weekend.

- High chance for more than 1 inch of rain this weekend with the heaviest rain expected Saturday afternoon through Sunday morning.

SHORT TERM

(Rest of today through Thursday) Issued at 1140 AM CDT Mon Sep 28 2026

We are still sitting pretty this Monday morning with surface high pressure keeping our wx exceptionally pleasant and dry.

On the regional maps, a weakening storm system remained in place along the northeast coast with a ridge axis just to our west.

Over the next couple of days, the coastal storm will continue to weaken and move farther away as the ridge axis builds over the TN Valley.

This will bring a big warmup with highs climbing well into the 80s for Tuesday, and 80s to lower 90s Wednesday and Thursday.

We are not looking for record highs at this point, but temperatures will be 10-15 degrees above normal.

Overnight lows that have been in the 40s and 50s will warm into the 60s.

Along with the warmth, southerly surface winds will develop, bringing increasing humidity into the area.

With September ending Wednesday, we are on track for the warmest and driest September on record for Nashville.

LONG TERM

(Thursday night through next Monday) Issued at 1140 AM CDT Mon Sep 28 2026

One big weather switch flipped last week when we had the end of 100 degree days and cooled down to normal.

Another big switch will flip late this week as abundant atmospheric moisture surges into the area.

We are starting the week with precipitable water values around the 10th percentile, but by Saturday, we will be around the 95th percentile.

This will set the stage for a rainy weekend.

Several systems are coming together to bring the suddenly unsettled pattern.

The first will be a disturbance with a pocket of tropical moisture coming up from the Gulf.

The next will be a northern stream shortwave and front.

Finally, the biggest feature will be a big southern stream low pressure system coming from the west.

This system will be pre-loaded with Pacific tropical moisture.

The interplay of these systems will make for a complex setup determining exactly when and how much rain we get.

Although there are model uncertainties about the evolution of this weekend's rain and how much we will receive, GEFS/ENS/GEPS ensembles are pointing toward a soaking rainfall with more than 1 inch likely.

There is a 40 percent chance for more than 2 inches and a 20 percent chance for more than 3 inches.

Rainfall is expected to be showery with limited thunderstorm activity, but some heavy downpours may occur, especially Saturday afternoon through Sunday morning.

We should be able to handle a lot of rain, but we will be watching for localized flood potential if some heavy bands set up.

Eventually the northern stream system will drop a front through the area, sweeping out the heaviest rainfall.

This may be Sunday or Monday.

It looks like cooler air will follow the front, perhaps with some post-frontal gloomy skies to start next week.