Monday, July 1, 2013

The Weather's Role in the Tragedy at the Yarnell Hill Fire...

As I'm sure you know by now, all but 1 of the 20 member team known as the "Granite Mountain Hotshots" was killed in the line of duty yesterday.  They were fighting the out of control wildfire known as the "Yarnell Hill" blaze in Arizona.

The small town of Yarnell is located about 60 miles to the Northwest of Phoenix and about 25 miles to the Southwest of Prescott, Arizona:

It is currently estimated that over 250 homes (approximately 65% of the total) have been destroyed in the community since the fire began on Saturday - the result of a lightning strike from an otherwise "dry" thunderstorm.

While all of the details surrounding the deaths of the firefighters are not yet clear, a quick examination of the data from yesterday as well as what is taking place again today suggests that the weather did, in fact, play a crucial role in the tragedy.

This time of the year, surface winds are typically of a Southerly or Southwesterly direction across the region.  Each afternoon, thunderstorms typically form along the edge of the higher terrain to the Northeast, and move toward the Southwest or West/Southwest.

The radar, satellite and lightning data mosaic below shows thunderstorm activity that is developing and moving Southwest toward the Yarnell blaze as of this writing:

As you can see by the surface weather observation table below, the wind shifted from Southerly earlier in the day to a NW-N direction as the thunderstorms passed over the Prescott airport (and note that the wind has since shifted back to the South after a 2-hour impact from the thunderstorms):

As the thunderstorms move toward Yarnell, the wind will shift there too, and if taken by surprise and/or with a sudden increase in speed, the results can be disastrous - just as we saw yesterday.

One tool that firefighters have at their disposal when caught by surprise includes an emergency "shelter", which is similar in construction to a light weight sleeping bag, but this one is coated in a heavily fire retardant material:

Ironically, the photo above was taken as part of a training exercise with the Granite Mountain Hotshots just last year.

So, with the information that the crew was supplied with similar emergency sheltering equipment yesterday, the question remains:  what happened?  Was the wind shift and resultant barrage of fire so immediate and intense that they had little or no time to react?  Will we ever know?

As difficult as it is to say this, the fact of the matter is that the location(s) and condition(s) of the firefighter's bodies when they were discovered should shed some light as to what action they may or may not have been able to take prior to becoming overwhelmed by the raging inferno.  Only time will tell for sure whether or not this was the case.

In the meantime, this entire situation provides another stunning glimpse at what can happen when a sudden and drastic change in the weather is juxtaposed with an ongoing natural disaster.

We certainly pray for comfort to the family and friends of those lost yesterday, and for strength and resilience to those who continue to fight the Yarnell Hill and other wildfires in the coming days.

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