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Texas Emergency Management ONLINE 2015 Vol. 62 No. 9

Texas Seasonal Wildfire and Weather Outlook

Part 1: Fall & Winter Wildfire Potential

Texas Emergency Management Digest cover page, Summer Edition 2005.

Looking ahead to fall 2015 and winter 2016, there are a couple of concerns that could promote increased wildfire activity.

The threats for increased wildfire potential this fall and winter include:

  1. Increased grass fuel loading across the state, especially in the plains regions
  2. The presence of dead brush and trees left over from the drought of 2011
Texas Emergency Management Digest cover page, Summer Edition 2005.

First is the effect of the above normal precipitation levels of late spring and early summer (see graphic to left). Record amounts were seen in many regions of the state during the month of May.

On top of this, above normal precipitation continued across the western plains regions of the state through the later parts of summer (see graphic below).

Texas Emergency Management Digest cover page, Summer Edition 2005.

The rains of spring and early summer resulted in a bumper growth of grasses similar to the image below in Taylor County near Abilene. The concern is that these grasses could become fuel for a wildfire.

Texas Emergency Management Digest cover page, Summer Edition 2005.

With the onset of a “flash drought” during the second half of the summer over the central and eastern regions of the state, this increase in grass loading did promote a corresponding increase in wildfire activity. With this grass loading in place going into the fall and winter there is a concern that it could also promote an increase in wildfire activity for these seasons as well. This is particularly the case for the plains regions where the late summer rains have continued to help support grass growth. When these grasses cure in the winter, they will represent a threat for increased wildfire potential.

Texas Emergency Management Digest cover page, Summer Edition 2005.

The second concern for increased wildfire potential is the presence of dead brush and trees left over from the severe drought of 2011. These dead trees increased difficulty of control for fires this summer, particularly in the Hill Country. An example of the complexity these fuels add to the fire environment can be seen in the image to the right. This was taken in Hays County during the latter part of summer. The grasses can carry fire into areas where dead trees are still present, allowing them to ignite and burn.

On the positive side, El Niño conditions are expected to continue into the winter months (see the accompanying fall and winter weather outlook).  El Niños typically provide the state with an increased chance for precipitation during fall, winter, and early spring. Under normal fuel loading conditions, wildfire activity is generally suppressed by the presence of El Niño. But this year there is the added threat of increased grass loading. This added loading will provide an extra dimension to the wildfire potential compared to what we normally see during El Niño years. With the grass loading present, especially in the plains regions, it is likely that the state could see periods of increased wildfire activity this winter. While conditions in the fall are generally unfavorable to increased wildfire activity, the loading could also have an impact depending on how the grasses respond to precipitation, when it occurs.

Part 2:  Fall and Winter Weather
The state of Texas received a large and substantial amount of rainfall—with many records broken—as we entered into the summer season, all courtesy of El Niño making a return for the first time in about five years. It is not unusual for El Niño to have a limited impact on the amount of rainfall in Texas during the summer months. We have clearly seen this occur over much of July and August as some parts of the state have witnessed a “flash drought.”  A flash drought is typically an onset of unusually high temperatures and little to no rain leading to a rapid decrease of soil moisture. In turn, parts of East Texas have gone from too much rain to a moderate/severe drought in a short amount of time.

El Niño refers to the large-scale warming of ocean temperatures over the east-central Equatorial Pacific Ocean. Going into the winter season, El Niño typically means above normal rain and below normal temperatures for Texas and much of the southeastern half of the United States. Figure 1 below shows how the Pacific Jet Stream dips further south and brings more moisture and rainfall into parts of California, Arizona, New Mexico and Texas. Conversely, when La Niña is present, the jet stream shifts further north, resulting in below normal rainfall and above normal temperature forecasts for Texas.

Texas Emergency Management Digest cover page, Summer Edition 2005.

Figure 1: NOAA Wintertime El Niño Pattern (NOAA)

Forecasters with the Climate Prediction Center (CPC) currently have an El Niño Advisory issued based on the ENSO Alert System. They are predicting a greater than 90 percent chance that El Niño will continue through the Northern Hemisphere winter 2015-16, and around an 85 percent chance it will last into early spring 2016. With a few weeks left before the official end of summer on September 22, much of the state should continue to expect above normal temperatures and below normal rainfall. As previously mentioned, El Niño impacts typically wane during the summer and are at their strongest during the winter period.

This can be seen on the CPC’s three-month outlook for September, October and November (Figures 2A and 2B). The opportunity for above normal rainfall begins to return mainly in north and west Texas along with below normal temperatures in the fall. An “equal chance” of above normal, below normal or normal rainfall and temperatures exists in east and southeast Texas.

Texas Emergency Management Digest cover page, Summer Edition 2005.

Figure 2A:  CPC Three-Month Outlook Precipitation for SON

Texas Emergency Management Digest cover page, Summer Edition 2005.

Figure 2B:  CPC Three-Month Outlook Temperature for SON


As we move further into fall and go into the winter season, the opportunity for above-normal rainfall begins to spread statewide, along with below normal temperatures. The images below (Figures 3A and 3B) are three-month outlooks provided by the CPC for October, November and December; November, December and January; and December, January and February.

Texas Emergency Management Digest cover page, Summer Edition 2005.

Figure 3A:  CPC Three-Month Outlooks for OND/NDJ/DJF

Texas Emergency Management Digest cover page, Summer Edition 2005.

Figure 3B:  CPC Three-Month Temperature Outlooks for OND/NDJ/DJF


To sum up, there are strong indications that Texas will encounter more rainfall and cooler temperatures as we head to the end of the year. El Niño is expected to peak in the late fall and early winter before beginning to taper off to a neutral phase.


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