My view of the August 21, 2017 Total Eclipse.

 

What an amazing event! The moon’s shadow gave a big show across America today and at 1:02 pm CDT it rushed over Lincoln, NE at over 1500 mph. Day turned to night, the temperature dropped and a 360 degree twilight ruled the midday.

First…my video!

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Screen capture from video during totality in Lincoln, NE. Shows the “eclipse twilight” surrounding the city. Photo by me (Nick Humphrey).

The temperature in Lincoln dropped from 81 degrees around noon to 77 degrees after 1 pm and totality. Many locations along the eclipse path experienced temperature falls of 3-5 degrees as a result of the passage of the Moon’s shadow. Meteorologists also observed (both on the ground and with satellite imagery) the collapse of convective cumulus clouds dependent upon surface heating to “bubble”, which was lost during the advanced partial and total eclipses.

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Cumulus cloud field impacted by the eclipse. Cloud field (12:42 pm CDT) dissipates by 2:32 pm CDT as totality approaches. Photo courtesy of AccuWeather Meteorologist Becky DePodwin. Lowering of temperature weakens upward convection currents likely limiting maintenance of cumulus clouds and leading to their dissipation in the absence of other lifting mechanisms.

You can watch the progression of the Moon’s shadow across North America below (video is only four seconds long so you’ll have to replay to see it more than once at a time):

All I can say is that this was one of most spectacular events of nature I’ve ever witnessed. I’ve witnessed multiple total lunar eclipses and while they are spooky (especially in the middle of the night), nothing can beat the powerful changes which a total solar eclipse can bring to the landscape.

The clouds, which were the most problematic for eclipse viewing in Nebraska ended up breaking enough to see totality itself, but also provided a canvas for the incredible glow of midday twilight. It was quite magical.

The next total solar eclipse in the Lower 48 is April 8, 2024. Totality in parts of Texas (which will include Austin and Dallas/Fort Worth Metro) could last nearly 4 1/2 min compared to the 2 min 40 sec max with today’s eclipse. If time and finances align, I definitely want travel for that one if I don’t live near it by then.

Anyone have any eclipse experiences they want to share? I’ll be checking out WordPress posts too! 🙂

PS-A view from a Omaha news station of the twilight colors with clouds HERE (video) within totality near Beatrice, NE, south of Lincoln.

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National Weather Service Sky Cover Forecast for Eclipse

Consider this the final forecast and here on out its whatever Mother Nature decides. Overall looks great for the West (0-30% cloud coverage), deteriorates significantly over the Plains/Midwest (50-70%), improves back to low coverage over southern IL and TN (where totality will be at or near max possible), and deteriorates again over South Carolina. 

Hoping for the best in Lincoln, Nebraska with 50-60% cloud coverage most likely transparent high clouds, however scattered opaque mid-level clouds are also possible which would diminish any serious solar viewing. My fiancé Cassie and I will head off to South Lincoln with our 1yr old and position ourselves at a location in view of the sun and the western sky (where the shadow will advance into town at 1500 mph). Whether we see the sun or on, it will turn to night at 1:02 pm CDT and last nearly 1 min 45 sec at our chosen location. We intend to have photos and I’ll also take video with my GoPro.

For 2017 Eclipse Coverage please follow me on Facebook or Twitter (see feeds on my main page for direct links). I will post on the progress of the eclipse on both platforms after the umbra’ landfall in Oregon at 10:16 PDT thru it’s exit from South Carolina after 2:50 pm EDT. Yes it’s only taking about a hour and a half for the umbra to blast across the US! 

I will do a post-eclipse photo/video post hopefully by this evening or tomorrow for WordPress 😊

Incoming shortwave radiation with eclipse effects as depicted by the experimental High Resolution Rapid Refresh Model (HRRRx) for 12:45 pm CDT Monday. Note the solar radiation “hole” which includes the umbra and “eclipse twilight”. (NOAA)

JPL 2017 Eclipse Simulator

Anyone want to know what the 2017 Eclipse will look like at your location with nice graphics and all? Check out this excellent simulator put together by NASA’s Jet Propulsion Laboratory. You’ll be able to animate the eclipse for any given location in the US from beginning to end and find out what to expect. I made a collection of some of the locations which will experience partial eclipses (all at their time of maximum eclipse). All these location were in areas of 75% or greater obscuration of the solar disk. Optical and atmospheric effects begin to take hold with 75% obscuration as incoming shortwave radiation from the sun is significantly reduced. Read more about that in my previous July post HERE if you haven’t already. Remember, however, that even with 99% obscuration, the sun will still be too bright and therefore too dangerous too look at directly without certified eclipse glasses. Direct viewing of the sun for multiple minutes can blind you, any amount can cause eye injury!

Seattle
Seattle, WA. My home city! 92% Obscuration.
Portland
Portland, OR. 99% Obscuration. So close to totality, yet so far!
San Francisco
San Francisco, CA. 75.5% Obscuration.
Denver
Denver, CO. 92% Obscuration.
Brookings
Brookings, SD. The location of my undergraduate alma mater South Dakota State University. 89% Obscuration.
Minneapolis
Minneapolis, MN. My Mom and much of my extended family lives here. They’ll take in the show. 83% Obscuration.
Dallas
Dallas, TX. 75% Obscuration.
Atlanta
Atlanta, GA. 97% Obscuration.
DC
Washington, DC. 81% Obscuration.
Jacksonville
Jacksonville, FL. 90.5% Obscuration.

Additional eclipse info for this post (such as max eclipse time) is courtesy of Xavier Jubier’s 2017 Total Eclipse Interactive Map.

Sky Conditions for August 21, 2017 Eclipse

The Great North American Eclipse is almost here! On Monday, the Moon’s inner shadow or umbra will touchdown over the open Pacific Ocean and rush toward a landfall in Oregon after 10:15 am PDT and exit the South Carolina Coast after 2:50 pm EDT. The shadow will be advancing across at around 1500-2000 mph. An incredible speed.

For an overview of the atmospheric phenomena to expect during the eclipse, see my previous late-July article on the August 21, 2017 Eclipse.

With the eclipse on Monday, the biggest concern is the weather…specifically sky conditions. The National Service, out of national interest in the eclipse (which will ONLY be seen in the United States) now has forecasts available, with special interest in sky condition forecasts.

Map
US National Weather Service Sky Condition Map (% sky cloud covered) valid 2 pm EDT Monday August 21st. Moon’s umbra will be over Nebraska at this time. 
Much of the eclipse path is *decent* (50% or less sky coverage forecast), although clear skies are extremely ideal. The best skies for totality are expected to be over the Northwest sector of the US, with greater cloud coverage (near 50% over the Central Plains/Missouri). There will be some improvement over Tennessee, but possible afternoon showers and thunderstorms may cloud up skies more significantly over extreme northeast Georgia and into South Carolina.

With that said…just remember…1) There’s more to the eclipse but totality! Regardless of whether you’re in the path or not, dealing with scattered clouds or not, enjoy the eclipse! Watch the crescents form in the shadows of trees, make a pinhole viewer (like this or this for example…I’m planning on making one!), if you have certified eclipse glasses or shades…safely observe the sun directly, and if you’re in a very deep partial (75%+) enjoy the effects of the weakening sun on temperature, sky and the animals. Also…2) For those in totality, all you need is that precious 1 or 2+ mins to be clear around the eclipsed sun. Hopefully, with that 50% or less sky coverage, that will be easier to achieve.


My Plans-

As you all may know, I live in Lincoln, NE…in the path of totality. As the city is literally on the northern edge of the shadow, there is a tight gradient for the length of totality; anywhere from tens of seconds on the north end of town, to 1 min 45 seconds on the south end of town. My house will see around 1 min 15 seconds. We had planned on going to Grand Island, NE about a hour and a half west of here to visit a relative of hers and see the eclipse at 2 min 35 sec (near max possible duration)…but our car has an issue which makes it not reliable for traveling on the highway! 😦 Literally found this out today! Extremely disappointed as there isn’t enough time for us to get the car fixed.  But considering we’re still IN totality vs. not, I can’t completely complain. So instead, we’ll be heading to the south end for the maximum length in Lincoln. I’ll have my GoPro set up on a mini-tripod to capture very high-res video of the last minutes before totality and during it. My fiance and I will also take lots of photographs. I will have updates on my Twitter and FB pages as the partial eclipse advances toward totality (feeds also can be seen from the website…but please follow me directly! 🙂 ).

It should be an exciting day! Everyone have safe viewing and have fun!

August 21, 2017 Eclipse is on its way! What to expect?

We’re now less than four weeks away from the historic total solar eclipse of August 21, 2017! This will be the first total solar eclipse in the contiguous United States since February 1979 when a total eclipse swept through northern Oregon, southern Washington, into Idaho, Montana and the Canadian Prairies. Much of the Northwest dealt with clouds in the coastal and western regions as cities such as Portland fell into a post-sunrise darkness.

Well now it’s 2017 and this eclipse is in a much better month…August. While this doesn’t guarantee good weather for any location along the path of totality; convection (thunderstorms) and cloud debris can cause issues on the Plains, while marine clouds can cause problems in the Pacific Northwest for example, generally quieter conditions with the jet stream and the domination of summer time high pressure and upper-air subsidence across the continent during the late summer means more opportunity for less cloud cover and quieter conditions across more parts of the country to view the eclipse in August than, say February.

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Path of umbra (inner lunar shadow) where totality will be observed as well as coverage of penumbra (outer shadow) where ONLY partial eclipse will be observed. The center line of the umbra will reach the Oregon Coast at ~17:16 UTC (1:16 pm EDT) moving at 2,416 mph and exit the South Carolina Coast at ~18:49 UTC (2:49 pm EDT) moving at 1,489 mph. ( map found on Wikipedia)
In order to assess the the most important aspect of observing an eclipse – sky conditions – the University of Idaho School of Natural Resources performed a climate analysis for the United States to determine the probability that a location will have clear skies at 10:30 am local time on August 21st. This time is picked because of the arrival of totality on the West Coast.

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Clear Sky Probability for the contiguous United States for 10:30 am local time August 21st. High probabilities are over portsions of the Western US, minus Western WA/OR and CA valleys where morning low marine clouds can occur. (U of Idaho College of Natural Resources)
While clear skies would be absolutely optimal for an eclipse, ESPECIALLY totality,  few to scattered cloud coverage (25-50%), while less fortunate in terms of direct solar photography and SAFE solar viewing, can still yield interesting observations leading up to and during totality. Because the umbra is quite thin, interesting atmospheric optics can occur. Although the area under totality becomes relatively dark, the light outside of the shadow can still be seen to observers. And the reflected light will appear to be twilight-like in color and glow. You could call it “eclipse twilight”. And with any cloud in the area, they will change colors or change in reflection of light as the darkness rolls over them, great for photographic and video effect. Just before totality, the sun itself will start to appear as if it’s “dying” in the final minute or two and the shadow will start to rapidly advance out of the western sky like a monster storm…except it’s not a storm 😀

In addition, regardless of scattered or no clouds, in the last min or so before (and after) totality, if you look at plain surfaces you may witness wavy motions like those in water known as shadow bands. These form as the focused, but rapidly weakening light of the sun is being distorted by the dense atmosphere of Earth. Those very near the totality path may also witness them.

This YouTube video I found some weeks ago shows both the prominent shadow bands and the “eclipse twilight” with clouds.

Now I’m a meteorologist. So when we talk about having a giant astronomical object blasting a shadow across a continent at 2000 mph and putting regions into nighttime in the middle of the day, a meteorologist is going to ask, how is this going to impact the weather?

For those at 75% percent partial eclipse and higher, the surface temperature will start to become depressed temporarily as the incoming solar radiation is reduced. This will be especially apparent for eclipses during the midday. As totality approaches, any winds may calm as a result of “fair weather convection” weakening as surface heating completely shuts down (this is where upward vertical motions produced by surface heating, leading to local winds die down).

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Here’s an EXCELLENT website using a Google Map layout where you can click on a location for eclipse “contact” times (start of partial, start and end of totality, end of partial) and maximum obscuration of the solar disk (areal coverage by the moon): HERE

In a couple weeks, numerical models will START to give us some distant idea of how the weather patterns may evolve for August 21st. I’m especially interested, because my location (Lincoln, NE) WILL experience totality. Will likely head to the south side of town to experience roughly 1 min 45 seconds of it and some of the very partial eclipse before that. It would be my first total solar eclipse since I was born and raised in Seattle but that event didn’t happen there and happened 5 yrs before I was born anyways.

Stay tuned in the coming weeks as weather updates come!