Detailing cloud forecast for the path of totality

The eclipse is almost here! We are less than 5 days from the big show! The timer is set for the moment the eclipse begins in the U.S., on the coast of Oregon.
The good news is that there does not appear to be any big weather features that will be affecting the country.No cloud shields from tropical storms or hurricanes are expected to reach the U.S., and there should not be any large scale, mid-latitude cyclones with large cloud shields. However, there will still be areas of clouds.

AccuWeather Astronomy friend David Fisherowski was practicing with is solar filters ahead of the eclipse. If you would like tips on observing the eclipse, check out this blog from Sky and Telescope. To see more of David's work. Check out his website Dave's Horizons.
Unfortunately, it will only takes one poorly timed cumulus cloud to block out totality. Before we dig into the cloud forecast, there are just a few things to remember. You will be able to see planets and some stars before and after totality. Even where it's cloudy for totality, it will still turn very dark and it should still be an impressive experience.

Pacific/Mountain Time Zone
We have reviewed the cloud climatology in previous blogs. In short, it is more likely to be clear the farther west you are in the country, except for the Oregon coast, where low clouds are likely. The weather pattern we are looking at will be a little different across other parts of the country, but in the West, not so much.

I'm optimistic about the northern Rockies to the interior Northwest. Monsoon moisture will be mostly shunted east of the total eclipse area. Plus, the timing of the eclipse is favorable for sky cover. Totality will be before most of the building clouds develop, that will lead to scattered afternoon thunderstorms in a typical summer pattern.
Central Time Zone
One area of concern is across Missouri into Kansas and Nebraska. This area has turned active with showers and thunderstorms recently. It looks like there could still be a bit of an upper-level weakness that could spawn a thunderstorm cluster or two on Monday, Aug. 21. Otherwise, I don't see any real big issues.
Eastern Time Zone
Things are looking good in the maximum eclipse area, east across Tennessee. Once into the southern Appalachians and South Carolina, it will be 2:30 p.m. local time. So, clouds will be building in what looks to be a hot and humid weather pattern.

It is a little too far out to trust computer models. They are showing big differences from run to run.
So, it will be a matter of luck being in between building showers and thunderstorms. I think the biggest trouble area for clouds will be near the South Carolina coast. The threat of a hurricane or tropical storm will be close enough to bring clouds to the Southeast. but the threat seems low.
Bottom line: the best viewing will be in the West. Eastern Oregon would be my pick for clear skies; however, at this point, you really shouldn't give up hope anywhere.
Thanks for reading. Just look up, you never know what you will see!
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