Anomalous snowfall across the high terrain of Arizona as well as lower elevation rainfall led to greater than normal runoff into the Salt and Verde watersheds. As a result of this, dam releases were conducted at multiple locations in these watersheds, leading to heightened flows in these rivers.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PSR wrote it up.
Anomalous snowfall across the high terrain of Arizona as well as lower elevation rainfall led to greater than normal runoff into the Salt and Verde watersheds. As a result of this, dam releases were conducted at multiple locations in these watersheds, leading to heightened flows in these rivers. Upstream releases led to additional releases from Granite Reef Dam, which initially began to cause impacts on the 4th when releases from the dam increased above 1,000 cfs. Granite Reef Dam releases continued to increase going through the month of March and at one point during the month was releasing nearly 40,000 cfs. Releases from this dam led to downstream flow in the normally dry Salt River, which runs through the Phoenix metro. The anomalous runoff into the Salt and Verde watersheds and the resultant dam releases led to numerous impacts along the Salt, Verde, and Gila Rivers, including multiple unbridged river crossings being flooded, multiple water rescues, and one recreational fatality. Flow in the Salt River continued downstream into the Gila River, causing more impacts along the way down to Painted Rock Dam. Releases continued through the remainder of the month and into April, resulting in prolonged impacts.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Phoenix, AZ wrote its last area forecast discussion before the first event at Mar 4, 2:47 AM MST, 1 hour 13 minutes earlier.
Area Forecast Discussion National Weather Service Phoenix AZ 247 AM MST Sat Mar 4 2023 .SYNOPSIS... Quiet weather conditions with warming temperatures across southcentral AZ will continue into early next week. Breezy to windy conditions across portions of SE CA tonight through Sunday remain the only impactful weather over the next several days. && .DISCUSSION... Skies are mostly clear this morning, as latest satellite imagery depicts drier air settling into southern Arizona. A low pressure system is currently pushing ashore across the Pacific Northwest, with the main impact in association with this system limited to breezy to windy conditions across SE CA tonight through tomorrow. Temperatures continue to trend warmer as mid-level heights continue to recover, but are expected to remain below normal through the early portions of next week. Zonal flow aloft across the Desert Southwest will persist over the next couple of days, as high-amplitude longwave troughing remains across the Pacific Northwest. This longwave trough will bring a highly energetic jet across the Great Basin through the weekend, but the main impacts from this system will remain north of the forecast area. Ensembles remain in good agreement through early next week in regards to the longwave trough persisting across the Pacific Northwest. Across the Desert Southwest, mid-level heights will continue to hold steady, resulting in little change to temperature trends early next week. During this period, temperatures will most likely remain below normal (90th percentile) in the lower 70s across the lower deserts. Beyond Tuesday, ensemble differences become more evident as the longwave troughing across the Pacific Northwest begins to dig across the Desert Southwest. The discrepancy going through the latter portions of next week is in regards to how deep and progressive this trough becomes and how it will impact the temperature trends locally. The ECMWF and CMC show a more progressive trough that traverses over southcentral AZ, while the GFS digs the trough deeper across the Desert Southwest Wednesday and Thursday. Thus, the range of possibilities by Thursday are quite large. A deeper trough would result in a cooler and potentially wetter trend, while a more progressive pattern would continue the dry conditions and may result in a warming trend. The latest NBM percentiles depicts these uncertainties well, as the 25th-75th percentile range for high temperatures Thursday and Friday range from the mid-60s to upper-70s. At this point, the latest forecast lies in the middle of the temperature scenarios (highs in the lower 70s), with PoP's remaining less than 10%. && .AVIATION...Updated at 0530Z. South-central Arizona including KPHX, KIWA, KSDL, and KDVT No aviation concerns expected during the TAF period. Light E winds this morning with periods of variability. Winds will begin to veer late in the morning and become more SW by mid afternoon before going back to the E tomorrow evening. Speeds will primarily be aob 8kt. FEW-SCT high cirrus clouds will be present through the forecast period. Southeast California/Southwest Arizona including KIPL and KBLH: Light and variable winds tonight will give way to S/SW breezes by late morning/early afternoon. Gusts will primarily be upwards of 20kt at both terminals, but some occasional 25kt gusts are possible. These higher gusts have a greater potential of occurring at IPL during the mid-afternoon hours. Some thin high clouds can be expected during the TAF period. && .FIRE WEATHER... A warming and drying trend will continue through the weekend. MinRH's will dip into the upper teens to low 20s percent by early next week as residual moisture exits the region, but overnight recovery will still remain good. No wetting rains expected over the next week. Winds will remain generally light across the region into next week, with the exception of SE CA, where winds across lower desert areas may see periodic gusts 20-30 mph beginning tonight and lasting into early next week. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...None. CA...None. && DISCUSSION...Young AVIATION...Worley FIRE WEATHER...Young
The national radar mosaic for the moment the first event began.
11 flood. Local standard time, as filed.
According to the Maricopa County DOT, McKellips Road between Alma School Road and SR 202 was closed due to flooding from the Salt River beginning on the 7th and continued into April. Timing based on water releases from Granite Reef Dam.
According to MCDOT, the unbridged Salt River crossing along 67th Avenue between Broadway Road and Southern Avenue was closed due to flooding beginning on the 12th and continued into April. Timing based on water releases from Granite Reef Dam.
According to MCDOT, the unbridged Gila River crossing along El Mirage Road between Southern Avenue and Indian Springs Road was closed due to flooding beginning on the 14th and continued into April. Timing based on water releases from Granite Reef Dam.
According to MCDOT, the unbridged Salt River crossing along Gilbert Road between Thomas Road and SR 87 was closed due to flooding beginning on the 14th and continued into April. Timing based on water releases from Granite Reef Dam.
Two people became stranded on top of their vehicle in the Salt River along 91st Avenue near Baseline Road after attempting to cross through the flooded roadway. The initial call for help occurred on the 17th around 1845 MST. They were safely rescued by the fire department via helicopter. No injuries were reported. Event timing is based on releases from Granite Reef Dam.
Buckeye Fire Department performed a water rescue at the unbridged Gila River crossing along El Mirage Road between Southern Avenue and Indian Springs Road on the 18th. The exact details surrounding the water rescue are unknown. The road had been closed since the 14th due to the elevated flow in the river. Event timing is based on releases from Granite Reef Dam.
Maricopa County Sheriff's deputies received a call around 1145 MST on the 18th of a reported drowning after an 81-year-old man fell out of his kayak and didn't resurface. The incident occurred near the Pebble Beach area along the Salt River. Other kayakers on the river pulled the man out and administered first aid but were not successful. The man was pronounced dead at the scene. Approximately 20 minutes later, a family kayaking downstream on the Salt River near the Phon D Sutton Recreation Area had to be rescued after their kayak capsized. The family managed to stay afloat by holding onto some bushes and trees. All of the family members were safely rescued via helicopter by the Maricopa County Sheriff's Office. Ongoing dam releases were resulting in strong currents in the river at the time of these incidents. Event timing is based on downstream Granite Reef Dam releases.
A man was swept away after attempting to walk through the flooded unbridged El Mirage Road crossing that goes through the normally dry Gila River between Southern Avenue and Indian Springs Road. The man was walking through the water while carrying his bicycle when he was swept away on the 17th. The man was successfully rescued with no injuries reported. Event timing is based on Granite Reef Dam releases.
Two people kayaking on the Salt River approaching the Phon D Sutton Recreation Area became separated before one of them capsized on the 19th. The capsized kayaker was able to hold onto trees while the Maricopa County Sheriff's Office worked to rescue him via helicopter. The man was safely rescued with no injuries reported. Ongoing dam releases were resulting in strong currents in the river at the time. Event timing is based on downstream Granite Reef Dam releases.
Two people were rescued after driving around road closure barricades and attempting to drive through a flooded roadway with a recreational vehicle. While attempting to cross the flooded roadway, the recreational vehicle was swept off the road. The incident occurred around 2100 MST on the 30th at the unbridged El Mirage Road crossing that goes through the normally dry Gila River between Southern Avenue and Indian Springs Road. The two people were safely rescued by the fire department via helicopter. No injuries were reported. Event timing is based on Granite Reef Dam releases.
Lake levels at Bartlett Lake quickly rose during the overnight hours Thursday night into Friday morning on the 16th-17th. Levels reportedly rose 10 feet during the overnight hours, leaving at least two camp trailers submerged in several feet of water. No injuries were reported.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flood, Maricopa | 2023-03-18 | 81 | Male | In Water | Direct |
| Flood, Maricopa | 2023-03-18 | 81 | Male | In Water | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2023Every state in 2023This day in weather historyWarnings in Arizona, March 2023
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1088517, 1088530, 1088544, 1090021, 1090023, 1090025, 1090054, 1090095, 1090100, 1090522, 1090574.