From the Cliff Mass Weather Blog
I have gotten a lot of inquiries about the weather on April 8, the day of the total solar eclipse of the sun over the eastern half of the U.S.
Our operational forecast models reach that far in time and have for a few days. But considering the uncertainty at such a long projection, I have refrained from commenting until now.
The model solutions are starting to settle down and I have increasing confidence that I can provide useful information. So let me do the first of several updates on the weather associated with the event.
The area of totality will extend from Texas to Ohio to northern Maine (see below).
Totality will occur at roughly 1800 UTC (11 AM PDT) for most of the path (earlier to the southwest, later to the northeast). Here in Seattle, only about 20% of the sun will be covered (see below). You would hardly notice this, even if the skies were clear.
Below is the forecast 700-300 hPa (10,000-30,000 ft) relative humidity, a good measure of cloud cover, at 1800 UTC 8 April based on the U.S. GFS model.
Portions of southwest Texas might have a good view, but I worry about viewing conditions over much of the Midwest. Some openings in Ohio and northern Maine.
But at this projection (270 hours), there is still substantial uncertainty. Only when we get within roughly 5 days (120 hr) will confidence be relatively high in the forecast.
To illustrate the uncertainty, let me show you are series of forecasts for the above humidity field for four different forecast projections, but verifying at the same time (1800 UTC 8 April). Specifically, you are viewing an animation of 288, 282, 276, and 270-hour forecasts of sea level pressure (solid lines) and the moisture field.
All have some kind of low-pressure system and a plume of clouds in the middle part of the country and it appears the solutions are converging. But there are significant changes between the forecasts.
For Seattle, the variations are quite large.
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An animation of the precipitation forecasts valid for the same eclipse time is shown below. Enough precipitation to get a Midwest eclipse watcher nervous. And not promising for western Washington.
Another approach for such a long-term forecast is to look at the forecasts of ensembles of many forecasts.
Below is the North American Ensemble Forecast System (NAEFS) prediction of clouds over Dallas/Fort Worth Texas over time. I put a red arrow at the time of the eclipse. Remember: an ensemble forecast shows the results of many different forecasts all valid at a certain time.
10 indicates total cloud cover. The horizontal line shows the median cloud cover for that location and the yellow box around the medium shows the range of 50% of the ensemble forecast members. (remember that the median is in the middle of a distribution of many forecasts, as many above as below).
Lots of clouds and lots of uncertainty at that location.
Anyway, if you are planning to go to the eclipse, don’t expect perfect conditions and be prepared to move, depending on the closer-in forecasts.
Like the site Ryan Hall, y’all, noting the models are just not good enough to do detailed cloud cover predictions that far out is just being honest.
Our local weather forecaster here in Oklahoma told us we will have to wait a few days to get a more accurate forecast of the weather.
I’m located just outside the path of totality a few miles so will get about 98 percent of the Sun blocked here.
I remembered seeing another solar eclipse in the past but couldn’t remember exactly when, but it turns out it was 1970, according to the internet. Such a handy invention! 🙂
https://www.timeanddate.com/eclipse/list.html?region=north-america&starty=1970&type=solar
I didn’t have any special glasses or telescope for viewing but I could go outside under an oak tree and see hundreds of little projections of the eclipse on the ground as the light shown between the leaves. It looks like the path of totality for this eclipse is following a similar path to the one in 1970 (see link).
It definitely got noticeably colder in 1970, as the Sun’s light was blocked. Get your weather stations ready to record!
California continues to see rain and snow in the mountains.
I remember an eclipse many years ago in Orlando. There was a noticeable drop in temperature, even though it was a partial eclipse.
If I remember correctly, during a total eclipse the temps can drop 20*F.
(Who’d a thought the Sun can effect the temperature! 😎
The weather and climate are intrinsically combined.
If they can’t accurately forecast the weather after next week, how the hell can they forecast the climate in 30 years time.
It’s all a scam.
Considering that the climate is the average weather over 30 years, predicting it forward 30 years is quite simple. You can say it’ll likely be the same as it was the last 30 years and you’ll land one in the ballpark. Predicting the weather exactly 30 years from today is impossible, unless you give it as probabilities.
Predicting climate change over the next 30 years is where it gets dicey. The Climate Change zealots simply look at past trends, and then extrapolate them forward. They usually cherry pick only the trends that fit their agenda. A key problem with this is that there are many repeating cycles in the weather that go up in magnitude, and then go back down. Some of these are moderately short like ENSO, the present El Nino, that gave us an unusually warm 2023, or longer like the multidecadal ocean cycles. There are even longer cycles like the multi-millennial cycles that gave us the Little Ice Age, Medieval Warm Period, and Roman Climate Optimum. All these have repeating but unpredictable magnitude and time periods. The scam is from the Climate Change crowd that ignore this.
I forget which streaming service it was, but I saw a “documentary” that was going to let us know what the climate would be like in 1000 years. Not 100 years, 1000 years.
Needless to say, I skipped over it.
We’re living in the Holocene, a brief inter-glacial period in the several million-year Pleistocene Ice Age. The Holocene has already been a bit longer than the last several interglacials, so I’ll predict that my place for writing this will be covered in the start of a mile thick ice cover, and there will be no weather here at all, and the temperature will be a bit below 32 degrees F in a thousand years.
Several members of my family live in the Lake of the Ozarks area and another In Branson. I’m interested in what they will have to report.
The weather and climate are intrinsically linked.
If you cannot accurately forecast the weather after a few days, how the hell are you going to forecast the climate over the next 20/30 years.
It’s all a scam.
They don’t use the same models to predict weather and climate. Weather and climate models work differently.
Weather models take data regarding current weather and then try to predict the conditions for individual locations.
Climate models take predicted conditions and from that try to predict what average temperatures, rainfall, etc. will be like.
Many of the things that matter the most to climate models, are completely ignored by weather models, because they change too slowly to matter to weather.
Weather models are marginally useful and are improving over time.
Climate models are complete bollux and there is no evidence that they have improved over the last 30 to 40 years.
The sky conditions during last total US eclipse in central South Carolina where we were was about a 50% cumulus cover at the start. By the time totality hit almost all the clouds had dissipated and the sky was basically clear. This was mid summer however when the Sun had a stronger influence on cloud formation. In fact the change in the atmosphere was one of the amazing parts of seeing it.
So cloud forecasts will be based on a normal day and areas where cumulus clouds are forecast will probably give you a better chance to see it. Stratus and overcast conditions probably not so much.
Thanks so much for such detailed information. At the moment it appears that Southern Vermont (98.6%) may be relatively clear. From my backyard, Stellarium-Web shows the eclipse about 40/235 with Jupiter, Venus and possibly Saturn visible. Should be fun, glad I don’t need to travel to see this. Did see a total one from here back in the late 80’s. Totality is an awesome moment, but I’ll settle for this.
Some fun facts:
Since the last eclipse was on August 21, 2017, this one will occur 6 years, 6 months, 6 weeks, and 6 days later…
Totality will cross over 7 US towns named Nineveh.
Nasa will fire 3 rockets from Wallops Island Virginia into the shadow to measure atmospheric perturbations during the eclipse.
“From my backyard, Stellarium-Web shows the eclipse about 40/235 with Jupiter, Venus and possibly Saturn visible. Should be fun”
You should also be able to see a comet, according to a report this morning.
Yes, thanks Tom. Looks like Comet 12P/Pons-Brooks will be just below Jupiter at 4.70 Magnitude 213/61 from where I am. Will need the binocs…
Thank you both for the web link.
I used to have the program itself on my previous PC.
That PC died.
(Hope I remember the old controls!)
It’s not looking good here, with 34 seconds of totality. I was hoping staying off the roads and enjoying a great view from the patio would work for us.
I will be in Waco for the Eclipse, and I’m hopeful the clouds will stay to the NW of Waco!
“Here in Seattle, only about 20% of the sun will be covered (see below). You would hardly notice this, even if the skies were clear.”
Expecting clear skies in Seattle is a fool’s errand.
In 2017 we had a near total eclipse. I loved the way the leaves in the trees acted as pinhole apertures, and cast the crescent of the sun on the ground.