Edhat Staff
Update by the National Weather Service
8:00 p.m., September 3, 2017
The EVACUATION WARNING for the Alamo Burn Area is now lifted. Wind & rain possible throughout evening, stay alert to your local conditions.
Update by the National Weather Service
4:19 p.m., September 3, 2017
An EVACUATION WARNING has been issued for the Alamo burn areas effective immediately due to potential flash flooding and debris flows in the area. Please be prepared to evacuate should the conditions change. If you have access or functional needs or if you feel threatened, leave now.
* Flash Flood Warning for… Northwestern Santa Barbara County in southwestern California… Southeastern San Luis Obispo County in southwestern California…Including the Alamo Burn area
* Until 545 PM PDT
* At 352 PM PDT, Doppler radar indicated a band of very heavy showers and thunderstorms across the northern mountains of Santa Barbara County and southeastern San Luis Obispo County. Radar
indicated rainfall rates up to one inch per hour with these showers and storms. Heavy rain will likely bring areas of flash flooding to portions of northern Santa Barbara County and southeastern San Luis Obispo. Of particular concern is the Alamo Burn area, where there will likely be mud and debris flows in addition to flash flooding.
Dime size hail and winds in excess of 40 mph will be possible with this storm. Flash flooding is also possible, especially over the Alamo Fire Burn area, with rainfall rates locally up to around one inch.
* Some locations that will experience flooding include…the Alamo Burn area…Orcutt…Sisquoc…and Highway 166 between Twitchell Dam and the Cuyama Valley.
PRECAUTIONARY/PREPAREDNESS ACTIONS…
A Flash Flood Warning for a recent burn area means that flooding and debris flows are imminent or occurring. Residents living in or immediately downstream should take immediate precautions to protect life and property. Quickly move away from the burn area only if it is safe to do so, otherwise shelter in place and move to a second story or the highest location in your home to stay out of the path of fast-moving water and debris flows.
Update by the National Weather Service
2:00 p.m., September 3, 2017
…FLASH FLOOD WATCH IN EFFECT UNTIL 10 PM PDT THIS EVENING FOR PORTIONS OF SOUTHWEST CALIFORNIA including recent burn areas…
The National Weather Service in Los Angeles/Oxnard has issued a
* Flash Flood Watch for a portion of southwest California, including the mountains of Los Angeles, Ventura, and Santa Barbara counties, as well as the Santa Clarita, San Fernando,
San Gabriel, Antelope, and Santa Ynez Valleys including recent burn areas.
* Until 10 PM PDT this evening
* Heavy rainfall with rates locally over 1 inch per hour will be possible across the watch area.
* In addition to the threat of flash flooding across the watch area, any thunderstorms that develop over the recent burn areas will bring the risk for debris flows. Due to the recent nature of the Whittier, Alamo, and La Tuna fires, they will be especially at risk for debris flows if thunderstorms develop over their areas.
PRECAUTIONARY/PREPAREDNESS ACTIONS…
Southern California residents, in or below the recently burned areas are urged to take the steps necessary to protect their property. Persons in the watch area should remain alert and follow directions of emergency preparedness officials.
Do not drive into flooded intersections as most flash flood fatalities occur in automobiles. Turn around…do not drown
Source: National Weather Service
September 2, 2017
Potential for thunderstorms and possible flash flooding near burn areas Sunday evening, take steps now to prepare a kit and make a plan.
…Increasing moisture from Tropical Storm Lidia will bring a threat of thunderstorms with locally heavy showers and possible flash flooding…
POTENTIAL IMPACTS
-
Isolated to scattered thunderstorms will become more widespread through Sunday
-
Gusty erratic winds near storms
-
Heavy downpours with localized flash flooding possible
-
-
Increasing humidity and warm overnight lows will add to heat discomfort
-
Risk of dry lightning fire starts tonight into early Sunday
WEATHER HIGHLIGHTS
Thursday through Saturday
-
Slight chance thunderstorms spreading from L.A. County up to near Point Conception tonight into early Sunday
-
Scattered to isolated showers and thunderstorms across the area Sunday afternoon and evening, shifting north after midnight
-
Possible flash flooding in heavy rain bands, especially for recent burn areas
-
Southeast wind gusts up to 50 mph for interior areas Sunday afternoon and evening
-
Continued hot conditions north of Point Conception Sunday with highs 98 to 104 away from the coast
-
Warm overnight lows (70’s across LA Metro Area, with 80’s in some valley and foothill locations)
-
Significant rise in humidities Sunday (30-50 percent inland areas)
FORECAST CONFIDENCE
- Moderate confidence in scattered thunderstorm threat Sunday afternoon and evening
- Low to Moderate confidence in risk of flash flooding in heavy rain bands
- High confidence in continued moderate to high heat risk Sunday due to heat and humidity
- Moderate to high confidence in gusty winds across the mountains
WEATHER SYNOPSIS
A strong upper level high pressure system will begin to shift east of the area tonight. The remnants of Tropical Storm Lidia will move northward tonight causing moisture to increase significantly through Sunday. There is a possibility of measureable rain across the area Sunday afternoon into Sunday night. The best chance of thunderstorms will be Sunday afternoon and evening across Los Angeles to Ventura Counties, spreading northward over Santa Barbara and San Luis Obispo Counties Sunday evening through Sunday night. Thunderstorms will cause gusty erratic winds, along with locally heavy downpours and possible flash flooding. In addition, there will be gusty southerly winds in the mountains Sunday afternoon and evening as the system passes to the west. Areas with the most morning sunshine, including areas north of Point Conception, are likely to see very hot conditions again on Sunday. Further south, cooler temperatures are expected. However, increasing humidities and warm overnight lows will continue heat impacts for all areas.
On Monday the moisture from Lidia will begin to move out of the region, but there will be a lingering slight chance of showers and thunderstorms across Southwest California in the morning shifting to the interior areas in the afternoon.
