Our incredibly hot and humid week is winding down.

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A front will sag southward today into tomorrow, bringing cooler, drier air and a bit of relief to those who have roasted in the east this past week.

The aforementioned relief will be brief, however, as we certainly have not seen the last of the ridging.

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Our ridge does not move on, but retrogrades westward, building once again over the central US before sliding back east early next week.

Watch that loop again. Notice the arrival of the 597 dm height line near the end of the loop? As we’ve discussed before, higher heights correspond to hotter, rising air below. In plain language: this next heat wave may be a bit more potent than this week’s heat, though it’s worth noting that there are discrepancies between models.

How hot it will be is still up for debate.

There is significant disagreement on Wednesday’s (likely the hottest day) temperatures. The ECMWF has been unwavering in suggesting some rather extreme heat, especially in the Southeast. Conversely, the GFS has been stubbornly sticking to temperatures that are hot, but not quite extreme.

A possible reason for these differences could be related to the forecast dewpoints. The ECMWF suggests lower dewpoints across the southeast while the GFS, though it does have a region of slightly lower dewpoints modeled, keeps them ultimately higher. Remember: dry air is easier to heat than moist air. If dewpoints do indeed end up verifying on the lower side, temperatures could soar a bit higher.

Lower dewpoints don’t really make much sense to me without some sort of frontal feature pulling in drier air. As the ridge will prevail for most of next week, this seems unlikely. Flow for the southeast when it is under a ridge comes from, well, the south/southeast which brings in the moisture from the Gulf of Mexico.  My point: I’d be cautious about expecting these extreme temperatures to verify.

BUT that doesn’t mean it won’t be hot. We’re in for another week of prolonged heat and humidity under the ridge. Temperature differences will shake out as we approach the start of the week and we’ll discuss high temperatures/record setting heat. For now, this is your early heads up to prepare once again to stay cool!