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Thunderstorms Across the Southeast U.S.; Elevated to Locally Critical Fire Weather in Colorado

A few strong to marginally severe thunderstorms are possible across the Southeast U.S. Friday. A Marginal Risk (Level 1 of 5) outlook has been issued. Strong winds and hail will be the main threats. Elevated to locally critical fire weather conditions will persist across south-central Colorado today due to dry conditions and gusty winds. Read More >

Cloud Forecast for Eclipse Time on August 21 in the GSP area:

As of 5:00 a.m. Mon Aug. 21:  Eclipse day has finally arrived, and we are expecting relatively good viewing conditions this afternoon.  The image below shows a model forecast of clouds this afternoon through the simulation of infrared (IR) satellite imagery for the time just after total eclipse.  IR imagery shows the cold temperatures of cloud tops.  The bigger and deeper clouds are, the colder their tops.  This images shows some cold, deep rain or thunderstorms along the coast, and some more shallow afternoon cumulus or lighter showers over the Southern Appalachian Mountains with some scattered cumulus over piedmont areas.  With some diurnal clouds and showers over the mountains, this would be the least favorable viewing location with the chances of clouds at around 50%.  Chances of clouds in the foothills is lower at 30 to 40% and as low as 20 to 30% in the piedmont.

Afternoon showers and thunderstorms are expected to develop over the mountains, with best chances over the higher elevations of the Balsam and Black Mountains, very typical for this time of year.  Some precipitation may develop across our extreme southern zones, but chances are pretty low, and for now no precipitation is expected along the I-85 corridor.

Finally, across parts of northeast Georgia and upstate South Carolina heat indices are likely to reach the middle and upper 90s Monday afternoon, with heat indices approaching 100 across our southern zones. Please take proper safety precautions for the heat and humidity. Remember to drink plenty of water, and know where a cooler location or shelter might be located.

Next update by: No further updates are scheduled

Simulated Cloud Forecast for 3pm

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Temperature Forecast

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What is now being called "The Great American Solar Eclipse" will cross over parts of Georgia, North Carolina, and South Carolina on August 21 2017.  What makes this eclipse "Great"?  It will be a total eclipse, which by itself is rare at any given location, and it will transect much of the Continental US, and will, thus, be seen by large numbers of people.

The total eclipse will begin near Newport, Oregon at 1:16 PM EDT and will end near Charleston, South Carolina at 2:48 PM EDT.  A partial eclipse will occur for the rest of the United States.

The last time a total eclipse was seen in South Carolina, North Carolina, and Georgia was March 7 1970.

 

August 21 2017 Eclipse Totality Path Map

 

 

Blue Line: Center of Totality

Red Lines: Northern and Southern Boundaries of Totality

Red Times: Times of Maximum Totality

 

Eclipse times at select locations within the total eclipse path (rounded to nearest minute):

Location Start of Partial Eclipse Start of Total Eclipse End of Total Eclipse End of Partial Eclipse
Robbinsville, NC 1:05 pm 2:34 pm 2:36 pm 4:00 pm
Bryson City and Franklin, NC 1:06 pm 2:35 pm 2:37 pm 4:00 pm
Cherokee and Sylva, NC 1:07 pm 2:36 pm 2:37 pm 4:00 pm
Highlands, NC and Clayton, GA 1:07 pm 2:36 pm 2:38 pm 4:01 pm
Cornelia and Toccoa, GA 1:07 pm 2:37 pm 2:39 pm 4:02 pm
Clemson and Seneca, SC 1:08 pm 2:37 pm 2:39 pm 4:03 pm
Greenville and Anderson, SC 1:09 pm 2:38 pm 2:39 pm 4:03 pm
Greenwood, Laurens, and Abbeville, SC 1:10 pm 2:39 pm 2:42 pm 4:04 pm

 

Cloudiness Climatology for 2-3 pm on August 21:

An important consideration is the possibility of clouds.  Afternoon cumulus clouds and thunderstorms are common elements of the early to late afternoons, especially over the Blue Ridge Mountains and foothills.  Generally speaking, clouds can be expected over any given location about 30 to 50 percent of the time at 2:38pm on August 21.  There is additionally an approximately 10% chance of rain at that particular time at any location in the area.

How Dark Will It Get?

During a total eclipse, the sun's corona is about as bright as a good full moon.  Additionally, the edge of the moon's shadow is, at most, only 35 miles away and considerable light will still come in from nearby areas not in total eclipse.  Generally speaking, it will be as dark during a total eclipse as it is about a half hour after sunset, or as dark as mid-twilight.

What Will be the Effect on Temperature?

Some noticeable drop in temperature will occur during the nearly 3 hours of partial and total eclipse.  The maximum in temperature drop due to the moon's shadow will actually occur shortly after the total phase because the continued partial eclipse will still allow more heat energy to escape to space than comes in from the sun.  How much the temperature drops depends on various factors such as the level of humidity (more humidity means less temperature drop), the level of clouds, winds, and time of day.  For the Aug. 21 eclipse with typical humidity levels in this part of the country and with few clouds, the temperature should drop a maximum of 5 to 10 degrees Fahrenheit.  The National Weather Service forecasts and keeps track of temperatures at the top of each hour, and given the 2:40pm time for the maximum effect of the eclipse on temperature, the 2pm and 3pm temperatures are expected to see some drop in temperatures of 2 to 6 degrees over what would occur had there been no eclipse.  This drop will be reflected in the forecast temperatures you get in the map above.

Safety Information:

NASA Eclipse Safety

If you value your sight, you should never look directly at the sun at any time, and for any reason.  It is no more or less dangerous to look at the sun during a partial eclipse than at any other time; it is almost always harmful.  Actually, the ONLY time it is safe to look directly in the direction of the sun without eye protection is during a total eclipse.  This is because the moon completely covers the sun at that time, blotting-out the harmful rays.  However, the total phase of this eclipse will only last a couple minutes, and one must be careful not to look at the sun before or after the total phase.

Link to NASA Eclipse Safety Site:  https://eclipse2017.nasa.gov/safety

 

Additional Safety and Other Tips:

--Many schools are operating on altered schedules on August 21.  Be aware of this in case employees need to make schedule adjustments for their children.

--Be prepared for cell service overloads; there may be service disruptions due to the increase in visitors using networks.

--Eclipse glasses should be worn for all but the total phase of the eclipse, sunglasses are not designed for looking directly at the sun, and do not offer sufficient protection.

--Give yourself plenty of time to get to your destination throughout the weekend.  Traffic will be heavy with large crowds going to and from events all weekend.

--Once you are at your eclipse event, stay there until well after the eclipse is over

--If you are driving during the eclipse, KEEP MOVING.  Do not stop your vehicle along interstates or any roadway.

--Make sure you have bottled water, sunscreen, a first aid kit, and eclipse viewing glasses.

 

If you do not witness the eclipse on August 21 2017, another one will be along eventually:

     The next time a total eclipse will seen in the Continental United States (but not GA, SC, or NC) will be April 8 2024.

     The next time a total eclipse will be seen in Georgia will be August 12 2045.

     The next time a total eclipse will be seen in South Carolina will be March 30 2052.

     The next time a total eclipse will be seen in North Carolina will be May 11 2078.

Links to more Information:

NASA website for Eclipses:

     https://eclipse.gsfc.nasa.gov/solar.html

NASA website for the August 21 2017 Eclipse:

     https://eclipse2017.nasa.gov

 

Sky Forecast by Area: