Cold fronts don’t make regular appearances around here in mid-July, but a weak one moves into North Alabama on Tuesday kicking off some locally-heavy thunderstorms as it passes. Just like the storms on Sunday and Monday: some get pounded with heavy, soaking rain while others miss out on it completely.
More clouds along with the chance of showers and storms keep temperatures in check Tuesday.
Expect a high around 90ºF with a heat index near 100ºF unless you’re the lucky one under the downpour. Storms thin out Wednesday and Thursday behind the weak front, but be ready for some more soakers and a few strong storms from Friday into Saturday.
Waves of storms: One thing is sure about summer storms in the South: you cannot know precisely when and where a single one will happen. We see environments where they are favorable, but those nitty-gritty details that can make or break outdoor work and play can’t be seen more than an hour or two in advance.
Storms on Tuesday follow the same general rules that most summer storms play by: uneven, hit-or-miss, very heavy in isolated spots, slow-moving, around 60 to 90 minutes’ worth of rain (maximum) in most cases.
- Timing? Storms start developing between 11 AM and noon Tuesday, and they’ll last until around 8 PM.
- Coverage? Our forecast ‘POP’ (probability of precipitation) is around 40 percent in that time frame. That’s relatively high confidence that storms develop in North Alabama and Southern Tennessee, but it’s low confidence that any single location will get more than 0.10” of rainfall. In other words, there will definitely be scattered storms in the area, but we can’t tell you specifically if it’s going to hit this neighborhood, that one, or both.
- What to expect? These storms will be slow-movers drifting generally from northwest to southeast at roughly 10-15 miles per hour. That slow movement combined with tremendous rainfall can lead to localized flooding! Be aware of rapidly rising water if you’re stuck in one of the bigger downpours.
Looking ahead to the weekend: The weak cool front passes south of the Tennessee Valley region Wednesday leaving us with a very small chance of any rain at all on Wednesday and Thursday. A storm system drags that front north again (as a warm front this time) on Friday; that should spark a few scattered heavy storms Friday afternoon.
Our chance of storms is highest Friday night and Saturday as that system passes overhead pulling another cold front through Tennessee and Alabama. Some of those storms could be rather strong, so we will keep an eye out for a potential severe weather threat Friday and Saturday. Slightly drier air helps limit the threat of storms (but doesn’t totally get rid of it) on Sunday.