Is it a Heat Wave or a BBQ Pit? Fires Add Smoke to the Misery

It was VERY smoky in the Northwest Wednesday unfortunately because of major fires in the Interior US and Canada.

Satellite image of Washington State showing abundant smoke over much of Puget Sound and the Strait of Juan de Fuca Wednesday.
Photo from Seattle’s Lake Washington of the sunset view Wednesday evening through the thick smoke haze produced from Canadian fires. (Photo by NWS Seattle on Twitter)

BELOW were the highs Wednesday for select cities. Southwest WA and Western OR are being particularly hit hard by this heat wave. Interior Western WA and Puget Sound were actually sparred some of the worst of the heat today by the smoke; it was thick enough to act as a cloud to dampen the radiation and limit warming in places such as Seattle. It remains to be seen if that will be the case Thursday. If not, the hottest day if the heat may very well be Thursday for Western WA (and about the same for Western OR). This, along with an Air Quality Alert in effect for much of Western WA/OR means those in the area will need to not only be careful with strenuous activity to avoid heat-related illnesses, but also avoid breathing problems, if sensitive to such smoke particulates.

(record highs in red)

WASHINGTON

Seattle (National Weather Service Office): 88

Seattle (International Airport): 91 – Old Record 89 (2009). Special Note: Seattle also shattered its daily record for warmest minimum temperature with a morning low of 69 (old record was 61 set back in 2015) and it ranks as the 2nd warmest daily minimum temperature on record.

Olympia: 91

Hoquiam: 89 – Old Record 81 (1993)

Vancouver: 102

Quillayute (North WA Coast): 98 – Old Record 89 (1993). Special Note: This was likely caused by easterly downslope winds; easterly surface winds flowing along the higher hilly terrain descends down the slopes resulting in “adiabatic heating” (compression heating from increasing pressure on the air molecules as the flow drops in elevation). This hot air blows into town and shoots the temperature up fast. This process occurs throughout the region and is the reason why it is typically a “dry heat” in Western WA/OR during heat waves. The heated air becomes dry, with little moisture added to it.

OREGON

Astoria: 93 – Old Record 88 (1939)

Portland (International Airport): 103 – Old Record 96 (1986)

Troutdale (East Portland Metro): 105 – Old Record 99 (1995)

Hillsboro: 105 – Old Record 99 (1939)

Salem: 107 – Old Record 102 (1939)

Eugene: 102 – Old Record 99 (1939)

Medford: 112 – Old Record 105 (1993)

Klamath Falls: 99 – Old Record 94 (1977)

As you see, for Oregon, there was a major theme in the records for Wednesday’s climate stations. It was the hottest day many of these locations had seen on this date since 1939.

Please be safe if you live in this region the next couple of days. Drink PLENTY of water, take breaks from the heat as necessary, use fans if you don’t have air conditioning (common problem in this region, I lived there without air conditioning and the summers statistically are generally getting warmer because of anthropogenic climate change…), and again, like me, I have asthma; if you don’t need to do anything strenuous outside DON’T! Just drive instead of walk or just stay inside, cool and relax. The slightly cooler weather (still above normal, however) starts Friday.

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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!