Alert archive / California / Flash Flood Watches in 2021
Flash Flood Watch 3, NWS Reno, NV
NWS Reno, NV issued this flash flood watch at Oct 20, 2021, 11:30 AM PDT for Lassen County, Plumas County, Sierra County, California. It took effect at Oct 21, 2021, 11:00 PM PDT. It was in force for 12 hr.
The area
The counties it named.
The facts
- Issued
- Oct 20, 2021, 11:30 AM PDT (18:30 UTC)
- In effect from
- Oct 21, 2021, 11:00 PM PDT
- Expired
- Oct 22, 2021, 11:00 AM PDT
- In force
- 12 hr
- Issued by
- NWS Reno, NV
- Flood severity
- None
Counties Lassen County, CA, Plumas County, CA, Sierra County, CA
The radar
The Beale AFB radar (KBBX), 107 km from the middle of the area, began a volume at 18:34 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Reno, NV (KREV), launched 12:00Z, 6.5 hours before the alert went out and 217 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2270 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 203 m²/s²
- 0-3 km storm-relative helicity
- 365 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
199 WGUS65 KREV 201830 FFAREV URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Reno NV 1130 AM PDT Wed Oct 20 2021 CAZ071-221800- /O.NEW.KREV.FF.A.0003.211022T0600Z-211022T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Lassen-Eastern Plumas-Eastern Sierra Counties- Including the cities of Sierraville, Westwood, Susanville, Loyalton, and Portola 1130 AM PDT Wed Oct 20 2021 ...FLASH FLOOD AND DEBRIS FLOW WATCH IN EFFECT FROM THURSDAY EVENING THROUGH FRIDAY MORNING... The National Weather Service in Reno has issued a * Flash Flood Watch for a portion of northeast California, including the following area, Lassen-Eastern Plumas-Eastern Sierra Counties. * From Thursday evening through Friday morning. * A short period of heavy rainfall is possible Thursday night and Friday morning in and downstream of the Dixie, Sheep, Walker, and Beckwourth burn scars. * Debris flows, ash flows, rock falls, and tree falls are possible with short bursts of heavy rainfall. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ BB
2 follow-up statements
208 WGUS65 KREV 212138 FFAREV URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Reno NV 238 PM PDT Thu Oct 21 2021 CAZ071-222145- /O.NEW.KREV.FA.A.0001.211024T0600Z-211025T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ /O.CON.KREV.FF.A.0003.211022T0600Z-211022T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Lassen-Eastern Plumas-Eastern Sierra Counties- Including the cities of Sierraville, Westwood, Susanville, Loyalton, and Portola 238 PM PDT Thu Oct 21 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 PM PDT THIS EVENING THROUGH FRIDAY MORNING... ...FLOOD WATCH IN EFFECT FROM SATURDAY EVENING THROUGH LATE SUNDAY NIGHT... The Flash Flood Watch continues for * A portion of northeast California, including the following area, Lassen-Eastern Plumas-Eastern Sierra Counties. * From 11 PM PDT this evening through Friday morning. * A short period of heavy rainfall is possible Thursday night and Friday morning in and downstream of the Dixie, Sheep, Walker, and Beckwourth burn scars. * Debris flows, ash flows, rock falls, and tree falls are possible with short bursts of heavy rainfall. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && The National Weather Service in Reno has issued a * Flood Watch for a portion of northeast California, including the following area, Lassen-Eastern Plumas-Eastern Sierra Counties. * From Saturday evening through late Sunday night. * Additional heavy rainfall from an atmospheric river will move into the region Saturday and continue into Sunday night. High snow levels will lower below 6000 feet by Monday morning. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ CAZ072-NVZ002-003-222145- /O.NEW.KREV.FA.A.0001.211024T1200Z-211025T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Greater Lake Tahoe Area-Greater Lake Tahoe Area-Greater Reno-Carson City-Minden Area- Including the cities of Truckee, Virginia City, Stateline, Tahoe City, Sparks, Glenbrook, Incline Village, Gardnerville, South Lake Tahoe, Markleeville, and Verdi 238 PM PDT Thu Oct 21 2021 ...FLOOD WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH MONDAY MORNING... The National Weather Service in Reno has issued a * Flood Watch for portions of east central California and western Nevada, including the following areas, in east central California, Greater Lake Tahoe Area. In western Nevada, Greater Lake Tahoe Area and Greater Reno-Carson City-Minden Area. * From late Saturday night through Monday morning. * Heavy rainfall from an atmospheric river will move into the region Saturday night and may continue into Monday morning. High snow levels will lower to near 6000 feet sometime Monday. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. This includes the Tamarack, Caldor, and Numbers burn scars. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions, especially along Interstate 80 between Truckee and Reno. Localized urban flooding is also possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. && $$ CAZ073-222145- /O.NEW.KREV.FA.A.0001.211024T1800Z-211026T0000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Mono County- Including the cities of Bridgeport, Lee Vining, Coleville, and Mammoth Lakes 238 PM PDT Thu Oct 21 2021 ...FLOOD WATCH IN EFFECT FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON... The National Weather Service in Reno has issued a * Flood Watch for a portion of east central California, including the following area, Mono County. * From Sunday morning through Monday afternoon. * Heavy rainfall from an atmospheric river will move into the eastern Sierra by Sunday morning and may continue into Monday afternoon. High snow levels will lower to near 7000 feet sometime Monday. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. This includes the Slink and Boot burn scars. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. && $$ BB
617 WGUS65 KREV 221756 FFAREV Flood Watch National Weather Service Reno NV 1056 AM PDT Fri Oct 22 2021 .The heaviest rain is moving out of the area this morning with the next system still on track to move into the region Saturday evening. CAZ071-230200- /O.EXP.KREV.FF.A.0003.000000T0000Z-211022T1800Z/ /O.CON.KREV.FA.A.0001.211024T0600Z-211025T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Lassen-Eastern Plumas-Eastern Sierra Counties- Including the cities of Sierraville, Westwood, Susanville, Loyalton, and Portola 1056 AM PDT Fri Oct 22 2021 ...FLOOD WATCH REMAINS IN EFFECT FROM SATURDAY EVENING THROUGH LATE SUNDAY NIGHT... ...FLASH FLOOD WATCH WILL EXPIRE AT 11 AM PDT THIS MORNING... The Flood Watch continues for * A portion of northeast California, including the following area, Lassen-Eastern Plumas-Eastern Sierra Counties. * From Saturday evening through late Sunday night. * Additional heavy rainfall from an atmospheric river will move into the region Saturday and continue into Sunday night. High snow levels will lower below 6000 feet by Monday morning. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop. && The Flash Flood Watch for a portion of northeast California, including the following area, Lassen-Eastern Plumas-Eastern Sierra Counties will expire at 11 AM PDT this morning. Please continue to heed remaining road closures. $$ CAZ072-NVZ002-003-230200- /O.CON.KREV.FA.A.0001.211024T1200Z-211025T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Greater Lake Tahoe Area-Greater Lake Tahoe Area-Greater Reno-Carson City-Minden Area- Including the cities of Truckee, Virginia City, Stateline, Tahoe City, Sparks, Glenbrook, Incline Village, Gardnerville, South Lake Tahoe, Markleeville, and Verdi 1056 AM PDT Fri Oct 22 2021 ...FLOOD WATCH REMAINS IN EFFECT FROM LATE SATURDAY NIGHT THROUGH MONDAY MORNING... The Flood Watch continues for * Portions of east central California and western Nevada, including the following areas, in east central California, Greater Lake Tahoe Area. In western Nevada, Greater Lake Tahoe Area and Greater Reno-Carson City-Minden Area. * From late Saturday night through Monday morning. * Heavy rainfall from an atmospheric river will move into the region Saturday night and may continue into Monday morning. High snow levels will lower to near 6000 feet sometime Monday. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. This includes the Tamarack, Caldor, and Numbers burn scars. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions, especially along Interstate 80 between Truckee and Reno. Localized urban flooding is also possible. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop. && $$ CAZ073-230200- /O.CON.KREV.FA.A.0001.211024T1800Z-211026T0000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Mono County- Including the cities of Bridgeport, Lee Vining, Coleville, and Mammoth Lakes 1056 AM PDT Fri Oct 22 2021 ...FLOOD WATCH REMAINS IN EFFECT FROM SUNDAY MORNING THROUGH MONDAY AFTERNOON... The Flood Watch continues for * A portion of east central California, including the following area, Mono County. * From Sunday morning through Monday afternoon. * Heavy rainfall from an atmospheric river will move into the eastern Sierra by Sunday morning and may continue into Monday afternoon. High snow levels will lower to near 7000 feet sometime Monday. * Debris flows, ash flows, rock falls, and tree falls are possible, especially on or near burn scars and steep terrain. This includes the Slink and Boot burn scars. Rises on small creeks and streams are expected, equipment in and near river and creek channels should be moved to safety. Rock falls in canyons and ponding of water on roads will create hazardous driving conditions. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop. && $$ DJ
Nearby
Flash Flood Watches in California, 2021Every flash flood watch in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.