Showing posts with label fire behavior. Show all posts
Showing posts with label fire behavior. Show all posts

Monday, August 10, 2009

Okanogan Highlands Lightning Fires; July 23rd thru 31st...

Thursday morning July 23rd, 2009 marked the beginning of an intense series of thunder & lightning storms across northeastern Washington state.
In this posting I'm going to provide several snapshots of what such an event looks like from the perspective of a firefighter. To convey the sense of what happened and what it means I'll be using several media from different sources and some images from other photographers. If a credit is not given, that photo is from my collection. Click on an image to enlarge. The first pic is a combination of photos to depicting nighttime lightning strikes over the Kettle River Range in Ferry County.

Here is the July 23rd, 2009 FIRE WEATHER PLANNING FORECAST FOR NE WASHINGTON from the National Weather Service - Spokane: ...
RED FLAG WARNING IN EFFECT FROM 2 PM THIS AFTERNOON TO 5 AM PDT FRIDAY FOR THE NORTHERN WASHINGTON AND NORTH IDAHO DISTRICTS DUE TO THE THREAT OF ABUNDANT LIGHTNING AND DRY FUELS...


This 2nd image/document is a lightning map. These are made available to firefighting agencies from the federal government and show the locations of both negative & positive lightning strikes. If your interested in how lightning strike maps work a Goggle search will pull up lots of info. In this map the area defined in red is the WA DNR Highlands District, my home ground; a geopolitical landscape spanning 1.3 million acres. Highlands District encompasses the northwestern portion of Ferry County and the Northeastern portion of Okanogan County. Corner to corner Danville to Fish Lake on paved roads it is more than a 2 hour drive on a good day. That's one big response area. Fortunately parts of the area spanned is within two national forests; the Colville and the Okanogan/Wenatchee both of which are partners in wildland firefighting. And both of which participated in the response to this series of lightning storm generated wildfires.
On this map there is a total of nearly 1,900 lightning strikes represented. A pretty hot storm from the perspective of a firefighter. The lightning storm episode I am recording here lasted from July 23rd to the 31st. During that span of time I'm certain the Highlands District received 2,500 to 3,000 lightning strikes.
When lightning fires occur it is usually from the strike hitting a tree and starting a fire at it's base, occasionally splitting the tree, sometimes blowing parts of it to pieces. Lighting strike ignitions also happen from lightning hitting fences, rock outcroppings, and occasionally buildings. But for the most part it is from the struck trees that wildfires are born. This image of the burning snag, by Highlands 126 Engine Leader Justin Wilson, is a good representation of a lightning struck tree. The fire can occur in the tree, on the ground or both. Often firefighters are faced with the dilemma of how to fall the burning tree. And unfortunately many firefighter fatalities happen due to trees & snags falling.
One of our rules to live by: Stay alert, keep calm, think clearly, act decisively.

In this, the fourth image/document, we see a portion of the DNR Regional view of ignitions occurring on the first day of the lighting bust starting on July 23rd. Highlands District is once again bounded in red. The blue 'tacks' represent lightning caused wildfires.
This might be a good place to explain that not all lightning caused fires are immediately detected. All firefighting agencies relay heavily on the general public to call in smoke & fires when observed. Additionally we use aircraft, lookouts, spotters and patrols to detect fires. In the case of the storms starting on the 23rd there was sporadic rains in the Okanogan Highlands. Prior to the storm the weather conditions were hot & dry - so, in other words, the stage was set for what we call "sleepers" to occur. Sleepers happen when the fuel bed is dry enough to ignite but moist enough not to readily burn. Thus the lightning ignition kindles in old snags, rotted stumps, under dry needle beds or in the duff. A sleeper can burn undetected for many days, often until the hot, dry conditions return. Add a little wind and that benign fire hidden in the tree roots can flare up to a real disaster. That's why firefighters are often seen in the middle of the storm chasing smokes on the mountainsides while those smokes are still showing (usually right after the fire has started).
Lightning fires occur in a wide variety of conditions as dictated by fuels, weather & topography, which by-the-way are the same elements that drive fire behavior. On a wildfire as seen above in this photo by Highlands 122 Engine Leader, Mark Kennard, on a small fire named 'Little Baldy' finding access to the burn was the most challenging part of the suppression process for the firefighters. Pictured here are firefighters (L to R) Jack Corbett, John Palmier & Mackenzie Wilson.

On the other hand if the fire behaves like the one pictured below, shortly after the passage of the storm the light fuels have dried out enough to carry the flame, the firefighter response must be quick & accurate to prevent damage to nearby timber and homes. Another of our rules to live by: Fight fire aggressively, but provide for safety 1st.



















Remember I said "fuels, weather & topography" dictate the type of fire. Here in a photograph by firefighter Mackenzie Wilson, on the 'Honey Bear' fire, the firefighters are faced with a heavy fuel, sleeper fire that has burned undetected for several days in the mountains outside Curlew WA. When the firefighters first put boots on scene on the Honey Bear fire it was already an acre in size and smouldering both above and below the ground. Thankfully nearby Republic Ranger District on the Colville National Forest had the 20 person Miller forestry crew available to assist the DNR fire staff. Pictured here in the foreground is Ferry/Okanogan Fire Protection District #14 firefighter Turu Wilkie, middle ground is Incident Commander, Mark Kennard (firefighters - whats wrong with this picture?) and an unknown Miller crew firefighter in the background.

And speaking of different types of fires... We'll switch over to the hotter and drier climate of Okanogan County. While the 'Whisky Strike; fire (named after Whisky Mountain - spelling is correct in this case) started during the lightning storm of July 23rd, it still hasn't been called out today (08/10/09). Not because it was so big, it wasn't at less than four acres in size; not because it is so steep, it is - the timber pictured here under the rotor drop is considered 'flat ground' on this fire. No, it is still burning because the shale & scree rock slides have over the years covered timber litter fuels over five feet below the surface. Digging mop-up pits in the steep, loose rock face of a fire like this is another hazard that firefighters face and must mitigate the risk to themselves and their crew. In this photo below, by Highlands Engine 123 Assistant Engine Leader Billy Monroe, we see a firefighting helicopter (rotor as it's known to firefighters) bucket dropping water on the steep slopes of the Whisky Strike blaze.

Above; in the 9th image of this series, another photo by Billy Monroe, we'll go to the 'Aeneas Torch' fire. Here we're looking over the shoulder of Highlands 123 Engine Leader, Jack Denison, down the valley to the northeast for a grand vista of Spectacle Lake. Jack is not only the Incident Commander (I.C.) but also functioning as the air-to-ground contact for the firefighting air resources attacking the blaze. This fire like many others during this series of lightning ignitions happened in a remote location beyond the ability of firefighters to reach with their engines, so its shoulder the gear time and hike in to the burning area on a hot, 100 degree summer day. Yep, you gotta' be tough to be a firefighter.

We talked a bit about 'sleepers' but occasionally lighting fires happen with little or no rain. When the fuels are dry, the relative humidity low and the temperatures hot, these fires can be off-to-the-races upon ignition. Fire Managers make every effort to have suppression resources available to send to each new start but a broad based lightning bust causing over 60 calls and igniting over 40 fires in the Highlands District taxed all firefighting resources. Fire suppression resources had missions re-prioritized and were routed to different calls. The DNR turned to it's partners in the fire protection districts for help. Strike Teams were assembled and assigned to incidents. Private dozers were hired to construct firetrail. And the heavy air tankers were called to scene to assist with fire suppression operations.
The Aero Union air tanker, number 22, seen here dropping retardant on the Aeneas Torch fire in this photo, by Billy Monroe, is a very effective firefighting resource. This and other air tankers were flying out of the Moses Lake airbase the afternoon of this lightning bust.

And while our eyes are to the sky, check out this DNR converted Cobra firefighting helicopter. Seen here approaching the Rin Con fire with a 250 gallon bucket load of water scooped out of the nearby Kettle River.

Another accurate hit for this aerial firefighting machine. In very short order this rotor delivered ten bucket loads of water strategically onto the fire and then flew in three 70 gallon blivet bags, which the firefighters secured on the slope above the burn area to use for mop-up later in the day. As Rin Con incident commander, Steve Kinley put it "that rotor just delivered 635 backpack bladder bags of water to this fire". Steve was really glad for that given it was nearly a two hour round-trip hike to the truck to fill a bladder bag & make it back to the fire.


Seen here in image #14, Highlands Engine 124 - Steve Kinley engine leader, & Shalene Jensen assistant engine leader, taking a well deserved break. As Kinley puts it to me, "I'm having a great day in the office, boss..."

Part of the process of what firefighters call 'initial attack' is to knock down the fire and establish firetrail or fireline around the burned area. This can be done in a number of ways with differing equipment with a varying result of impact & success. The most common method of containing a fire is by hand digging fireline around the burned area. In heavy timber establishing a handline capable of
holding the fire in check takes a lot of work. 20 person fire crews like the Highlands 20 or the private contract Miller Forestry Crew pictured here assisting DNR & FPD firefighters are specialists at fireline construction.

As can be seen by reviewing the above, there is a lot that goes on in the realm of fire suppression in the wake of a major thunder & lightning storm. We've only touched on the tip of it here. A few small fires suppressed by an assortment of firefighting resources.

Housed at the NE Region compound of the Washington State Department of Natural Resources, NE Washington Combined Communication Center - NEWICC Dispatch logged in approximately 114 lightning fires during this episode - 98 of those fires were within a three day period resulting from responses from 181 calls.


I think when all the data is accounted for, all the weather & fire records compared we will recognize the July 2009 lightning bust as a historical one in volume of lightning strikes and number of fire starts. Thankfully there was some rain showers with that storm front and this period will not be noted for number of acres burned. With all of the above fire activity combined, during a very hot period of the summer there was less then fifty acres burned.

A tip of my hardhat to the firefighters, fire managers, duty officers, dispatchers and support staff who made this successful job possible...

Foster
Special thanks to the following firefighters for sharing their photos:
Mackenzie Wilson, Billy Monroe, Mark Kennard, & Justin Wilson.
To learn more:



Colville National Forest: http://www.fs.fed.us/r6/colville/

Okanogan / Wenatchee National Forest: http://www.fs.fed.us/r6/wenatchee/

National Weather Service - Spokane: http://www.wrh.noaa.gov/otx/


Sunday, February 22, 2009

National Day of Mourning - 2009 Victorian bushfires

Today, February 22nd, has been declared a national day of mourning in Australia due to the 2009 Victorian bushfires. 210 people dead, 1900 homes burned to the ground, 7,500 people homeless and hundreds of thousands of acres burned.
In the midst of a long warming trend coupled with drought conditions the weather took a turn for the worse with hotter than normal temperatures and windy conditions. Both natural fire starts and arsonists caused ignitions and the situation soon exceeded the capacity for firefighters & other emergency responders to control. The results are disastrous.
Fire threatening houses west of Bendigo Australia.

While there are still many details from Australia's worst fires on record to come in I reflect on the times in NE Washington when the conditions line up against us firefighters. Exceptionally hot summer days, with high winds and unstable atmospheric conditions forcasted. It is under those conditions we have seen fires like Hangman Hills, Castle Rock & Rockey Hull fire ravage our area. Another, Fire Storm '91 spread across NE WA with 92 fires ignited in a single, dry afternoon when winds hit 50+mph. 911 Centers were getting a call every 60 seconds. More than 3,000 calls came into the centers overwhelming them all. Alarms were dispatched in "triage" fashion with only life-threatening or structure threatening fires receiving resources reassigned from other incidents or fires. One hundred and fourteen homes were destroyed that afternoon and one fatality occurred. Some people would say "we were lucky". But from the trenches, I'll tell you this, which I know to be true - each fireline that holds, each engine company that accomplishes it's mission, each air drop hitting it's target and every hot, gritty, shovel full of dirt a firefighter uses to knock down a small bite of flames is the foundation of that "luck". These are the reasons firefighters are dedicated to training, committed to responding and willing to go the extra mile when the situation gets so bad that others flee to save their own lives. While I am deeply proud to be a member of the world-wide firefighting community, my hard-hat is off to the firefighters and citizens of Australia in this dark & painful hour.
Foster
Photo above of Australian homes threatened - photographer unknown. All the rest of the following photographs are from my personal collection.
A forest fire rapidly spreading through mixed pine & fir timber stand. This is what we refer to as a fire "going vertical" where it spread into the forest canopy.
A very intense forest fire threatening trees in northeastern Washington state. Available fuel on the ground combined with brush below the timber allows
large amounts of heat to develop during dry conditions.

Resulting fires can be difficult to contain and do significant damage to forest, soils and homes within it's path.

As the main fire grows in intensity & size burning embers carried aloft and landing in front of the main blaze start new spotfires. If not controlled these spotfires multiply the problem of containment, increase the fire size and result in very difficult problems for firefighters.
To see actual images of the 2009 Victorian bushfires
Australian Red Cross
For info on FIRESTORM '91