Looming rainstorm may suppress wildfire danger but raise other issues in California
By
Alex Sosnowski, AccuWeather senior meteorologist
Published Nov 15, 2019 12:15 PM EST
A storm has the potential to bring locally drenching rain to part of the southwestern United States and may mark an end to the fire season, including in parts of California, next week.
The arrival of the rainy season is much later than average in the region and is likely to be one of the latest starts on record -- and dry weather will persist over much of the region into Tuesday. In some areas, there has been no rain in months.
The grueling dry conditions have set the stage for abundant fuel for wildfires in the form of parched vegetation. At the same time, more frequent wind events than normal have fanned the flames this fall. So far in 2019, a total of over 250,000 acres have been charred by blazes in California, according to the California Department of Forestry and Fire Protection. While the acreage burned is below the five-year average of 404,368 acres during the same time frame, massive wildfires have threatened communities and forced officials to issue mandatory evacuations on short notice.
However, a change is on the way that many may welcome.
A storm is forecast to develop not only near the surface but also at the jet stream level of the atmosphere over California during the middle of the week.
Rising air from the storm will cause moisture to gather, which will lead to the formation of clouds and eventually allow areas of rain to break out.
It is possible that moisture from Tropical Storm Raymond off the coast of Mexico feeds in and gives the storm a boost that enhances the rain in some areas during the middle and latter part of next week.
While a mosaic of showers is forecast from the storm beginning around Wednesday, it is possible that the rain will become locally heavy. Areas of rain may then persist into Friday.
As rain begins to fall, the combination of the buildup of oil on area roads from months of dry weather combined with the fallen water will make for extra slippery conditions. These conditions can be dangerous at intersections and on the ramps of highways.
After the rain has been falling for a while, it tends to wash away much of the oil and roads then tend to become less hazardous.
Enough rain may fall to end the fire season in some areas and significantly inhibit the risk of wildfires for weeks in others.
In a scenario where heavy rain falls, the rain can lead to flash and urban flooding and could trigger incidents of mudslides and other debris flows, especially in recent burn scar locations.
With the delay in the onset of the rainy season, many areas in the southwestern United States have been experiencing building drought.
Most places in California have returned to abnormally dry conditions, while a large part of the Four Corners states is experiencing moderate to severe drought.
"The heaviest rain may fall just east of California and over Arizona," AccuWeather Senior Meteorologist Rob Miller said.
"The mountains to the north and east of Phoenix could be most prone to flash flooding and mudslides in this particular setup," Miller said.
However, pockets of moderate rain may also develop in parts of Southern California, Nevada and/or in other recent burn scar locations.
Widespread rainfall totals of 0.50 to 1.50 inches are forecast to fall over the Southwestern states with this event. However, some locations can get much less rainfall, especially in the upper and lower deserts of southern California. An AccuWeather Local StormMax™ of 4 inches can occur in parts of Arizona.
"Arroyos, which are dry stream beds, may quickly fill with water and pose a risk to hikers and others," Miller said.
The storm and its clouds and areas of rain will follow a weak to moderate wind event over California that is likely to raise the risk of wildfire ignition and rapid spread this weekend.
Download the free AccuWeather app to get the latest updates on the storm and how it might affect your area. Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
Report a Typo
News / Weather Forecasts
Looming rainstorm may suppress wildfire danger but raise other issues in California
By Alex Sosnowski, AccuWeather senior meteorologist
Published Nov 15, 2019 12:15 PM EST
A storm has the potential to bring locally drenching rain to part of the southwestern United States and may mark an end to the fire season, including in parts of California, next week.
The arrival of the rainy season is much later than average in the region and is likely to be one of the latest starts on record -- and dry weather will persist over much of the region into Tuesday. In some areas, there has been no rain in months.
The grueling dry conditions have set the stage for abundant fuel for wildfires in the form of parched vegetation. At the same time, more frequent wind events than normal have fanned the flames this fall. So far in 2019, a total of over 250,000 acres have been charred by blazes in California, according to the California Department of Forestry and Fire Protection. While the acreage burned is below the five-year average of 404,368 acres during the same time frame, massive wildfires have threatened communities and forced officials to issue mandatory evacuations on short notice.
However, a change is on the way that many may welcome.
A storm is forecast to develop not only near the surface but also at the jet stream level of the atmosphere over California during the middle of the week.
Rising air from the storm will cause moisture to gather, which will lead to the formation of clouds and eventually allow areas of rain to break out.
It is possible that moisture from Tropical Storm Raymond off the coast of Mexico feeds in and gives the storm a boost that enhances the rain in some areas during the middle and latter part of next week.
While a mosaic of showers is forecast from the storm beginning around Wednesday, it is possible that the rain will become locally heavy. Areas of rain may then persist into Friday.
As rain begins to fall, the combination of the buildup of oil on area roads from months of dry weather combined with the fallen water will make for extra slippery conditions. These conditions can be dangerous at intersections and on the ramps of highways.
After the rain has been falling for a while, it tends to wash away much of the oil and roads then tend to become less hazardous.
Enough rain may fall to end the fire season in some areas and significantly inhibit the risk of wildfires for weeks in others.
In a scenario where heavy rain falls, the rain can lead to flash and urban flooding and could trigger incidents of mudslides and other debris flows, especially in recent burn scar locations.
With the delay in the onset of the rainy season, many areas in the southwestern United States have been experiencing building drought.
Most places in California have returned to abnormally dry conditions, while a large part of the Four Corners states is experiencing moderate to severe drought.
"The heaviest rain may fall just east of California and over Arizona," AccuWeather Senior Meteorologist Rob Miller said.
Related:
"The mountains to the north and east of Phoenix could be most prone to flash flooding and mudslides in this particular setup," Miller said.
However, pockets of moderate rain may also develop in parts of Southern California, Nevada and/or in other recent burn scar locations.
Widespread rainfall totals of 0.50 to 1.50 inches are forecast to fall over the Southwestern states with this event. However, some locations can get much less rainfall, especially in the upper and lower deserts of southern California. An AccuWeather Local StormMax™ of 4 inches can occur in parts of Arizona.
"Arroyos, which are dry stream beds, may quickly fill with water and pose a risk to hikers and others," Miller said.
The storm and its clouds and areas of rain will follow a weak to moderate wind event over California that is likely to raise the risk of wildfire ignition and rapid spread this weekend.
Download the free AccuWeather app to get the latest updates on the storm and how it might affect your area. Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
Report a Typo