A composite image from NASA's Terra satellite of the southwestern quadrant of the United States and the Pacific Ocean off California and Baja, Mexico. (Image: NASA Worldview) Last night I was trying to figure out how to use remote sensing imagery to depict the broiling heat wave that has settled in over the Southwestern United States and is beginning to bulge outward like a blob of magma. So I did what I often do: I explored the latest composite images from NASA's dynamic duo of satellites: Terra and Aqua. The image above is what I came up with: a portion of Terra's June 26th composite view, which takes in part of the Pacific Ocean and much of the West stretching from California at upper left through Nevada and Utah to Colorado at upper right (Denver is in the extreme upper right corner), and also including New Mexico, Arizona and parts of Mexico. I was struck first by the fascinating cloud details in the Pacific. More about that in a minute... Next, I spotted the wisps of smoke rising from wildfires in the Rockies (in both Colorado and New Mexico — can you spot them?). And then my eye wandered across the Southwest. It is remarkably cloud free because of a massive area of high pressure. Here's a snippet about it from the forecast discussion posted by the National Weather Service in Las Vegas:
.SYNOPSIS...A STRONG RIDGE OF HIGH PRESSURE WILL CONTINUE OVER THE DESERT SOUTHWEST THROUGH THE WEEKEND AND INTO NEXT WEEK. THIS WILL RESULT IN NEAR RECORD OR RECORD TEMPERATURES ON FRIDAY WITH ALL TIME RECORD HIGHS POSSIBLE IN SOME AREAS OVER THE WEEKEND. AN EXCESSIVE HEAT WARNING IS IN PLACE FOR MUCH OF THE AREA INTO EARLY NEXT WEEK FOR THIS EXPECTED INTENSE AND POSSIBLY DANGEROUS SITUATION.
The high temperature forecast for Monday, July 1 shows broiling temperatures for large parts of the West. (Map: National Weather Service) Vegas, baby! — you're possibly heading for a record-setting 116 degrees F on Saturday, if the forecast is right. (The average high for that date is a relatively balmy 103, according to Wunderground.com's almanac.) And if that's not warm enough for you, check out Furnace Creek in Death Valley: 128 is forecast for tomorrow, which would tie an all-time high record for June 28, as well as the record for highest temperature in June at that spot, according to the National Weather Service. Vegas and Death Valley will be hot? No shock there. But that bubble of high pressure is expanding, and by Sunday and Monday it is forecast to bring temperatures in the high 80s and even low 90s to places like Portland and Seattle. There is a broader climatic context to this, of course: global warming. In fact, research shows that record high temperatures have been occurring twice as often as record low temperatures. Before I end this post I want to get back to the fascinating detail in the Pacific Ocean portion of the image. I think those bright white criss-crossing lines in the cloud deck are ship tracks. But even more intriguing, to me at least, is a feature that almost looks like a miniature hurricane. You'll have to click on the satellite image to see it. Actually, there are at least two such features. One is rather large, in a large indentation along the coast of Baja. I think it's caused by a massive eddy in the winds swirling through the bay. But the cyclonic feature I'm most interested in is farther up the coast and smaller. It has a very well defined eye-like structure. Can you spot it? That will be the subject of my next post...
