Red Flag Conditions Fan Flames

There are currently at least nine active fires in Central and Western Wyoming. The most active smoke producer at the moment is the Red Rock Fire located between Dubois and Jackson; if you click on the image below, you will be taken to an animated satellite image that loops from Tuesday evening through Wednesday morning so you can see the fires in action!

As of 1pm Tuesday Afternoon, the smoke plume from the Red Rock Fire was already clearly visible on satellite. More smoke was visible from other fires as the afternoon progressed. Click here for the latest visible satellite image; otherwise, click on the image above to see an animated visible satellite loop of the smoke that was produced from the fires.


So what creates "Red Flag Conditions?"

a. A combination of dry, warm, unstable and windy conditions, that in the judgment of the Fire Weather Forecaster, creates conditions favorable for extreme fire behavior.


b. Conditions favorable for extreme fire behavior:
-20 foot winds sustained or frequent gusts of 25 mph or greater, or
-a Haines Index of 5 or 6 with somewhat lighter winds (a Haines Index of 5 or 6 indicates that the atmosphere is very dry and unstable, if it wasn't so dry then there would probably be thunderstorms), in combination with a dry lower air mass with surface relative humidity of 15% or less.


c. Widely scattered or greater coverage of Dry Lightning or widely scattered or greater coverage of thunderstorms after an extended dry period, even though some or most of the thunderstorms are expected to be wet (rain reaches the ground and accumulates to greater than or equal to 0.10 in)


Why was there a Red Flag Warning in this case?

It was hot:  (Yesterday's Maximum Temperatures)

 

It was dry:  (Yesterday's Minimum Relative Humidity) (expressed as a percentage)

 

And an Approaching system interacted with high pressure over the four corners region to increase the surface pressure gradient, and therefore, the wind speeds.


How should the general public react to a Red Flag Warning when one is issued?

A Red Flag Warning means that fires that already exist or that are started could quickly grow out of control. Use caution around fire and take care to not start a new one. If a fire does start, know that it could quickly become unmanageable.

If you must have a camp fire, put it out completely and be sure to practice proper fire safety techniques. If you use a bar-b-que, do not dump the hot coals and be sure to extinguish it completely.

Take care when sharpening tools, mowing the lawn, welding, or participating in any other activity that could cause sparks.

For more information on how to use fire properly and how to protect your home from wildfire, visit the Wyoming Firewise site or pick up some tips from the CDC.


 

How does the rest of the week look?

Hot and dry, but a little less windy. The ridge of high pressure begins to break down toward the end of the week; bringing back the possibility of thunderstorms.

 

The above graph shows three things at once: The heights are at the top. When heights rise, susually temperatures follow. The middle set of lines respresent the temperature of the airmass just above the surface, usually as the airmass warms, so does the surface. The bottom set of lines show how the surface temperature is expected to react to the rising/lowering heights.

The current time is on the left, as you move to the right, time progresses. Sunday's conditions are represented at the far right hand side of the graph.

Click on the image for a full resolution version.

The above graph shows three things at once: The heights are at the top. When heights rise, susually temperatures follow. The middle set of lines respresent the average wind speeds; as heights raise and lower in a short amount of time, usually the overall wind speed increases. The bottom set of lines represent the relative humidity at the surface.

The current time is on the left, as you move to the right, time progresses. Sunday's conditions are represented at the far right hand side of the graph.

Click on the image for a full resolution version.

Looks like an extreme weather week! A lot of heat followed by another round of thunderstorms. Keep an eye on our homepage for the latest, and be sure to find us on Facebook!



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