Friday, August 8, 2014

Notes on Washington's Big Burn of 2014: Weather Charts

A map of the fire progression of the Carlton Fire Complex provides a sense of how this fire blew across the landscape in two days when conditions were very bad. Truly amazing that no one was killed.  

The Google earth image below gives a general sense of the area where the fire complex took place. Classic fire prone area of dry forest mixed with grass and brush land. 

This area is potentially subject to fire just about every year. It is the edge of tree habitat. Wet enough for trees, but subject to long dry periods that are subject to fire with more grassy areas burning more frequently and thicker forest being less frequently at risk of fire. The tree line moves around based on fire frequency and intensity. 

All sorts of factors come into play: length of time since the last fire, land management., age of tree stands, mix of vegetation, types of grass, slope aspect, elevation and of course the recent weather leading up to the fire and the weather during the fire. For the Carlton Complex the weather conditions for a two day period when the fire spread rapidly were clearly really bad - very hot and windy.  

I took a gander at the weather leading up to this rather bad fire season in central Washington and there is a general pattern between the stations that can be seen. A very wet February that brought total precipitation up to normal and in some cases well above normal followed by a very dry April, May and June with above average temperatures followed by a very hot July. July 2014 was the hottest on record in Wenatchee. Throw some lightning strikes onto this weather pattern in July and there will be bad fires. 

Very wet February and early March, then very dry with a very hot July 

Chief Joseph 
This site is east of the fire area but has a long weather record dating back to the 1940s
Wet February followed by drier and warmer than normal and then very hot July 

Near where several fires stared in the upper Methow Valley
Very wet February and early Mach then bone dry and warm and then very hot

Similar pattern wet February and early March then dry and warm and then really hot.

In looking at some of the area that was in the burn zone I did some before and after looking and noted there are a lot more homes in portions of this fire prone area.

1991 east of Methow

2013 east of Methow

I do not know how the above area did. It is a matter of how well fire protected the homes were combined with just what the fire conditions were when this particular area burned.

This is tough business and difficult policy. Brad Plummer has what has become the typical fire season article explaining how policy and funding are not matched with a nice mix of references the-us-forest-service-is-running-out-of-money-to-fight-wildfires. Washington State Department of Natural Resources puts huge efforts into fighting fires as well as well as local communities. But for at least a couple of days there was little anyone could have done.     

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