Alert archive / Arizona / Flash Flood Watches in 2021
Flash Flood Watch 7, NWS Tucson, AZ
NWS Tucson, AZ issued this flash flood watch at Aug 30, 2021, 2:01 AM MST for 6 counties in Arizona. It took effect at Aug 31, 2021, 11:00 AM MST. It was in force for 27 hr.
The area
The counties it named.
The facts
- Issued
- Aug 30, 2021, 2:01 AM MST (09:01 UTC)
- In effect from
- Aug 31, 2021, 11:00 AM MST
- Expired
- Sep 1, 2021, 1:55 PM MST
- In force
- 27 hr
- Issued by
- NWS Tucson, AZ
- Flood severity
- None
Counties Cochise County, AZ, Graham County, AZ, Greenlee County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ
The radar
The Tucson radar (KEMX), 61 km from the middle of the area, began a volume at 09:01 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
Tuscon, AZ (KTUS), launched 00:00Z, 9.0 hours before the alert went out and 49 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
- 199 J/kg
- Mixed-layer CIN
- -48 J/kg
- Mixed-layer LCL
- 3172 m above ground
- 0-6 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 46 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
599 WGUS65 KTWC 300901 FFATWC URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Tucson AZ 201 AM MST Mon Aug 30 2021 AZZ501>515-302215- /O.NEW.KTWC.FF.A.0007.210831T1800Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Western Pima County-Tohono O'odham Nation-Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County- Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains- Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains-Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Ajo, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Safford, Bisbee, Vail, Clifton, Organ Pipe Cactus N.M., Hannagan Meadow, Sells, and Green Valley 201 AM MST Mon Aug 30 2021 ...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY LATE MORNING THROUGH LATE WEDNESDAY NIGHT... The National Weather Service in Tucson has issued a * Flash Flood Watch for a portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tohono O'odham Nation, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley, Western Pima County and White Mountains of Graham and Greenlee Counties. * From Tuesday morning through late Wednesday night. * Increasing tropical moisture will help to develop showers and thunderstorms capable of producing heavy rainfall. The threat increases Tuesday afternoon, continuing into Wednesday. * Locally heavy rainfall combined with a saturated ground will likely result in flash flooding of washes, small streams, and poor drainage areas. Burn scars from past and more recent wildfires will be especially prone to flash flooding and debris flow. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ RH
5 follow-up statements
095 WGUS65 KTWC 302116 FFATWC Flood Watch National Weather Service Tucson AZ 216 PM MST Mon Aug 30 2021 AZZ501>515-311130- /O.CON.KTWC.FF.A.0007.210831T1800Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Western Pima County-Tohono O'odham Nation-Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County- Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains- Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains-Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Ajo, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Safford, Bisbee, Vail, Clifton, Organ Pipe Cactus N.M., Hannagan Meadow, Sells, and Green Valley 216 PM MST Mon Aug 30 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING THROUGH LATE WEDNESDAY NIGHT... The Flash Flood Watch continues for * A portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tohono O'odham Nation, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley, Western Pima County and White Mountains of Graham and Greenlee Counties. * From Tuesday morning through late Wednesday night. * Increasing tropical moisture will help to develop showers and thunderstorms capable of producing heavy rainfall. The threat increases Tuesday afternoon, continuing into Wednesday. * Locally heavy rainfall combined with a saturated ground will likely result in flash flooding of washes, small streams, and poor drainage areas. Burn scars from past and more recent wildfires will be especially prone to flash flooding and debris flow. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ WJM
529 WGUS65 KTWC 310933 FFATWC Flood Watch National Weather Service Tucson AZ 233 AM MST Tue Aug 31 2021 AZZ501>515-312300- /O.CON.KTWC.FF.A.0007.210831T1800Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Western Pima County-Tohono O'odham Nation-Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County- Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains- Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains-Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Ajo, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Safford, Bisbee, Vail, Clifton, Organ Pipe Cactus N.M., Hannagan Meadow, Sells, and Green Valley 233 AM MST Tue Aug 31 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 AM MST THIS MORNING THROUGH LATE WEDNESDAY NIGHT... The Flash Flood Watch continues for * A portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tohono O'odham Nation, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley, Western Pima County and White Mountains of Graham and Greenlee Counties. * From 11 AM MST this morning through late Wednesday night. * Increasing tropical moisture will help to develop showers and thunderstorms capable of producing heavy rainfall. The threat increases Tuesday afternoon, continuing into Wednesday. * Locally heavy rainfall combined with a saturated ground will likely result in flash flooding of washes, small streams, and poor drainage areas. Burn scars from past and more recent wildfires will be especially prone to flash flooding and debris flow. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ KRG
974 WGUS65 KTWC 312033 FFATWC Flood Watch National Weather Service Tucson AZ 133 PM MST Tue Aug 31 2021 AZZ501>515-011415- /O.CON.KTWC.FF.A.0007.000000T0000Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Western Pima County-Tohono O'odham Nation-Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County- Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains- Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains-Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Ajo, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Safford, Bisbee, Vail, Clifton, Organ Pipe Cactus N.M., Hannagan Meadow, Sells, and Green Valley 133 PM MST Tue Aug 31 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY NIGHT... The Flash Flood Watch continues for * A portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tohono O'odham Nation, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley, Western Pima County and White Mountains of Graham and Greenlee Counties. * Through late Wednesday night. * The combination of deep tropical moisture and an upper-level disturbance will produce widespread showers and thunderstorms capable of producing heavy rainfall. The heaviest rainfall will occur this afternoon into early Wednesday morning. Showers and thunderstorms will persist into Wednesday night. * Locally heavy rainfall combined with a saturated ground will likely result in flash flooding of washes, small streams, and poor drainage areas. Burn scars from past and more recent wildfires will be especially prone to flash flooding and debris flow. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ CWR
162 WGUS65 KTWC 010753 FFATWC Flood Watch National Weather Service Tucson AZ 1253 AM MST Wed Sep 1 2021 AZZ501-502-010900- /O.CAN.KTWC.FF.A.0007.000000T0000Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Western Pima County-Tohono O'odham Nation- Including the cities of Organ Pipe Cactus N.M., Sells, and Ajo 1253 AM MST Wed Sep 1 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of Southeast Arizona, including the following areas, Tohono O'odham Nation and Western Pima County has been cancelled. The Flood Watch is cancelled. $$ AZZ503>515-012300- /O.CON.KTWC.FF.A.0007.000000T0000Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County-Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains-Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains- Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Bisbee, Vail, Clifton, Hannagan Meadow, Safford, and Green Valley 1253 AM MST Wed Sep 1 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT... The Flash Flood Watch continues for * A portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley and White Mountains of Graham and Greenlee Counties. * Through late tonight. * Increasing tropical moisture and a passing weather disturbance will continue to help develop showers and thunderstorms capable of producing heavy rainfall. The threat continues through late tonight. * Locally heavy rainfall combined with a saturated ground will likely result in flash flooding of washes, small streams, and poor drainage areas. Burn scars from past and more recent wildfires will be especially prone to flash flooding and debris flow. PRECAUTIONARY/PREPAREDNESS ACTIONS... You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$ KRG
338 WGUS65 KTWC 012055 FFATWC Flood Watch National Weather Service Tucson AZ 155 PM MST Wed Sep 1 2021 AZZ503>515-012200- /O.CAN.KTWC.FF.A.0007.000000T0000Z-210902T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Upper Santa Cruz River Valley/Altar Valley-Tucson Metro Area-South Central Pinal County-Southeast Pinal County-Upper San Pedro River Valley-Eastern Cochise County below 5000 feet-Upper Gila River Valley-White Mountains of Graham and Greenlee Counties-Galiuro and Pinaleno Mountains-Chiricahua Mountains-Dragoon and Mule and Huachuca and Santa Rita Mountains-Catalina and Rincon Mountains- Baboquivari Mountains- Including the cities of Sierra Vista, Mount Lemmon, Douglas, Mount Graham, Chiricahua NM, Marana, Willcox, Summerhaven, Canelo Hills, Benson, Nogales, Picacho Peak State Park, Kitt Peak, Tucson, Mammoth, Madera Canyon, Oracle, Bisbee, Vail, Clifton, Hannagan Meadow, Safford, and Green Valley 155 PM MST Wed Sep 1 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of Southeast Arizona, including the following areas, Baboquivari Mountains, Catalina and Rincon Mountains, Chiricahua Mountains, Dragoon and Mule and Huachuca and Santa Rita Mountains, Eastern Cochise County below 5000 feet, Galiuro and Pinaleno Mountains, South Central Pinal County, Southeast Pinal County, Tucson Metro Area, Upper Gila River Valley, Upper San Pedro River Valley, Upper Santa Cruz River Valley/Altar Valley and White Mountains of Graham and Greenlee Counties has been cancelled. Isolated to scattered showers and a few thunderstorms with brief heavy downpours remain possible through tonight but coverage will be limited. Thus, the Flash Flood Watch has been cancelled. The Flash Flood Watch is cancelled. Please continue to heed remaining road closures. $$ GL
The office that day
Everything else NWS Tucson, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 5:32 PM MST | Special Weather Statement | TWC | Pinal | 43 min |
| Aug 29, 6:49 PM MST | Special Weather Statement | TWC | 41 min | |
| Aug 29, 6:53 PM MST | Severe Thunderstorm Warning | TWC | Pima | 18 min |
| Aug 29, 7:46 PM MST | Special Weather Statement | TWC | Graham | 44 min |
| Aug 29, 8:06 PM MST | Areal Flood Advisory | TWC | Graham | 3 hr |
| Aug 30, 3:38 PM MST | Special Weather Statement | TWC | Pima | 52 min |
| Aug 30, 3:41 PM MST | Special Weather Statement | TWC | 49 min | |
| Aug 30, 3:45 PM MST | Special Weather Statement | TWC | Pima | 45 min |
| Aug 30, 4:06 PM MST | Areal Flood Advisory | TWC | Pima | 114 min |
| Aug 30, 4:24 PM MST | Special Weather Statement | TWC | 36 min | |
| Aug 30, 4:32 PM MST | Special Weather Statement | TWC | 43 min | |
| Aug 30, 4:50 PM MST | Severe Thunderstorm Warning | TWC | Pima | 40 min |
| Aug 30, 4:51 PM MST | Areal Flood Advisory | TWC | Pima | 100 min |
Nearby
Flash Flood Watches in Arizona, 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.