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Politics & Government

Flood Advisory and Green Flag Alert

The National Weather Service has issued a flood advisory for Sierra Madre, and the city has issued a green flag alert for mudslides and debris flow.

It's raining hard in Sierra Madre today, and the National Weather Service predicts that the precipitation will continue through tonight.

Doppler radar indicates moderate to heavy rain over the Southland today, with the heaviest rain in the San Gabriel Mountain Foothills. Rainfall rates are expected to average one quarter to one third of an inch per hour.

The NWS has issued a flood advisory for Sierra Madre. Ponding of water on roads, low-lying areas and intersections is possible.

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There is also a slight chance of thunderstorms, which could bring brief but intense downpours.

The city has issued a green flag alert.

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A green flag alert means there is an 80 to 100% chance of rain, and residents should get ready for the possibility of evacuation and keep an eye on weather forecasts. This includes residents of the Upper and Lower Canyon as well as any resident whose property abuts the hillsides burned by the Santa Anita Fire.

The rain is expected to taper off late in the evening. Monday is expected to be clear but chilly with a high of 62 degrees.

The city would like to remind residents of its emergency flag alert system:

Stage One: Green Flag - Activated under a prediction of 80 to 100% chance of precipitation. Affected residents should get “READY” for potential evacuation. This includes keeping a close watch on weather forecasts.

Stage Two: Yellow Flag - Activated with an L.A. County Phase 1 mudflow forecast. This is described as small, isolated debris and mudflows possible at specific locations. Affected residents should get “SET” to leave their homes and may choose to voluntarily evacuate. Please note that all vehicles must be off the streets in potential mudflow areas during Yellow Flag alerts.

Stage Three: Red Flag - Activated with an L.A. County Phase 2 or 3 forecast. Phase 2 includes moderate debris and mudflows at more widespread locations. Phase 3 - the potential exists for significant debris and mudflows to be widespread. Affected residents should “GO”, meaning they should immediately evacuate, and vehicles should not be parked on the streets.

The city has identified a number of streets that will need to be clear of all vehicles during a Yellow Flag or Red Flag alert: Mount Wilson Trail, Churchill Road, Skyland Drive, Fern Glen, Fern Drive, Idlehour Lane, Canyon Crest Drive, Orange Drive, Woodland Drive, Brookside Lane, Sturtevant Drive, Sunnyside Lane and Yucca Trail.

The Yellow and Red Flag Alerts will trigger vehicles being towed from these streets at the owners’ expense.

When possible, flags will be displayed indicating one of three stages of emergency. Be sure to check back with Patch, the city's website, Facebook/Twitter page, e-mail alerts, SMTV3, AM 1630, or simply call City Hall or the Police Department to confirm the current stage of emergency. The city may not always have the ability to change these flags the moment conditions or forecasts change.

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