A late winter weather system impacted southeast Arizona March 11-13. This system along with anomalously high moisture caused the Catalina, Rincon, and White Mountains to receive over a foot of snow above 6500 feet.
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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 TWC wrote it up.
A late winter weather system impacted southeast Arizona March 11-13. This system along with anomalously high moisture caused the Catalina, Rincon, and White Mountains to receive over a foot of snow above 6500 feet.
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 Tucson, AZ wrote its last area forecast discussion before the first event at Mar 11, 5:14 AM MST, 8 hours 46 minutes earlier.
Area Forecast Discussion National Weather Service Tucson AZ 514 AM MST Mon Mar 11 2019 .SYNOPSIS...Showers are already ongoing across southeast Arizona this morning. Expect this trend to continue through the day with the heaviest valley rain and mountain snow later this evening through Tuesday. Rain and snow will likely be heavy at times with even the occasional rumble of thunder. By Thursday, the weather will improve with a gradual warming trend into the weekend. && .DISCUSSION...Current forecast remains on track with the biggest changes to upgrade the Winter Storm Watch to a Warning and to extend the White Mountains into Wednesday as snow will continue through at least the late afternoon/evening. Additional changes were made to POPs and QPF/Snow amounts as overnight guidance trended wetter. Even with the changes, snow amounts remain in the 8-18 inch range for elevations above 6500 feet with the highest amounts near the peaks and favored upslope regions. QPF amounts were nudged slightly upward, which puts the valleys easily in the 0.5" to 1.0" range, with localized areas over 1" in foothills and favored S/SW slopes. Liquid amounts/SWE for the mountains will range from 1.5" for most mountain locations to over 2.0" in the White Mtns. Timing still looks good, with isolated to scattered showers across a majority of the area this morning. Additional development is expected across most of the area by the afternoon with a slight chance of thunderstorms. By tonight and through Tuesday morning, this should be the heaviest precip. This will occur as the surface low pressure moves into the Gulf of California. In response, a weakening occluded front will push into southern AZ. Along the frontal boundary, a solid shield of precip will form. Moderate to locally heavy rain with embedded thunderstorms are expected. Due to the increasing PWATS, strong lift, and available instability, rainfall rates will likely exceed 0.5" inches per/hr, which will likely lead to minor flooding issues in urban areas and along washes/streams. Washes and streams exiting the high terrain will pose the greatest risk. Although minor flooding is likely, significant flooding is not expected. Valley rain and mountain snow continues into Tuesday as the closed low moves across SE AZ. Due to the impressive cold pool, LIs will fall negative aiding in thunderstorm development. Brief heavy rain and heavy mountain snow will continue during the afternoon. By early evening, instability will wane and the closed low will be filling/exiting the region, thus precip chances decrease. Valley rain showers and mountain snow showers will continue across the White Mountains. By Wednesday evening and into Thursday, snow will finally end for the White Mountains. However, cool west/northwest dry flow will keep temperatures below average through at least Saturday. Thereafter, temperatures may climb to average or slightly above. Last item of note, is the chance for a weak weather system to move through the area Saturday night through Sunday, with isolated showers. Kept the forecast on the dry side, as uncertainties exists. && .AVIATION...Valid through 12/12Z. Precipitation has moved into the region this morning.all terminals. Expect scattered -SHRA to persist throughout the day today. Winds should increase during this afternoon, from 15-25 knots, with localized gusts approaching 35 knots. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect a windy and wet day today, as a dynamic system takes hold of the region. The most intense mountain snow and valley rain will be from tonight into Tuesday. A ridge will build in by the end of the work week, with warming temperatures and dryer conditions. && .TWC WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 2 PM this afternoon to 5 PM MST Wednesday for AZZ510. Winter Storm Warning from 8 PM this evening to 8 PM MST Tuesday for AZZ511>514. && Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
The national radar mosaic for the moment the first event began.
2 winter storm. Local standard time, as filed.
Snow began falling early in the afternoon of March 11th and continued into the 13th. SNOTEL observations reported 12 to 18 of snow at Hannagan Meadow.
Snow began the evening of the March 11th and continued into the evening of the 12th. By the afternoon of March 12 a foot of snow had fallen in the Santa Catalina Mountains. Mount Lemmon Highway was closed to everyone but residents for a time due to heavy snow.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2019Every state in 2019This day in weather historyWarnings in Arizona, March 2019
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: 814215, 814216.