Alert archive / California / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 13, NWS Sacramento, CA
NWS Sacramento, CA issued this severe thunderstorm warning at Apr 9, 2026, 7:14 PM PDT for San Joaquin County, Stanislaus County, California. It was in force for 31 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Apr 9, 2026, 7:14 PM PDT (02:14 UTC)
- Expired
- Apr 9, 2026, 7:45 PM PDT
- In force
- 31 min
- Issued by
- NWS Sacramento, CA
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 50.0 mph
Counties San Joaquin County, CA, Stanislaus County, CA
The radar
The San Francisco radar (KMUX), 87 km from the middle of the area, began a volume at 02:16 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.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The nearest sounding before it
Reno, NV (KREV), launched 00:00Z, 2.2 hours before the alert went out and 333 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
- 29 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 2279 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 140 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
529 WUUS56 KSTO 100214 SVRSTO CAC077-099-100245- /O.NEW.KSTO.SV.W.0013.260410T0214Z-260410T0245Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Sacramento CA 714 PM PDT Thu Apr 9 2026 The National Weather Service in Sacramento has issued a * Severe Thunderstorm Warning for... East central San Joaquin County in central California... Central Stanislaus County in central California... * Until 745 PM PDT. * At 714 PM PDT, a severe thunderstorm was located near Riverdale Park, or 8 miles west of Ceres, moving north at 15 mph. HAZARD...Quarter size hail. SOURCE...Radar indicated. IMPACT...Damage to vehicles is expected. * Locations impacted include... Modesto, Ceres, Manteca, Riverbank, Patterson, Ripon, West Modesto, Riverdale Park, Shackelford, Salida, Empire, Westley, Bret Harte, Bystrom, Grayson, Del Rio, and Keyes. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 3745 12103 3751 12123 3780 12119 3768 12084 TIME...MOT...LOC 0214Z 201DEG 13KT 3756 12110 HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...1.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...<50 MPH $$ NR
2 follow-up statements
860 WWUS56 KSTO 100225 SVSSTO Severe Weather Statement National Weather Service Sacramento CA 725 PM PDT Thu Apr 9 2026 CAC077-099-100245- /O.CON.KSTO.SV.W.0013.000000T0000Z-260410T0245Z/ San Joaquin CA-Stanislaus CA- 725 PM PDT Thu Apr 9 2026 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM PDT FOR EAST CENTRAL SAN JOAQUIN AND CENTRAL STANISLAUS COUNTIES... At 724 PM PDT, a severe thunderstorm was located over Riverdale Park, or near Ceres, moving north at 15 mph. HAZARD...Quarter size hail. SOURCE...Radar indicated. IMPACT...Damage to vehicles is expected. Locations impacted include... Modesto, Ceres, Manteca, Riverbank, Patterson, Ripon, West Modesto, Riverdale Park, Shackelford, Salida, Empire, Westley, Bret Harte, Bystrom, Grayson, and Del Rio. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 3748 12101 3753 12123 3780 12119 3768 12084 TIME...MOT...LOC 0224Z 201DEG 13KT 3760 12108 TORNADO...POSSIBLE HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...1.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...<50 MPH $$ NR
169 WWUS56 KSTO 100242 SVSSTO Severe Weather Statement National Weather Service Sacramento CA 742 PM PDT Thu Apr 9 2026 CAC077-099-100250- /O.EXP.KSTO.SV.W.0013.000000T0000Z-260410T0245Z/ San Joaquin CA-Stanislaus CA- 742 PM PDT Thu Apr 9 2026 ...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL SAN JOAQUIN AND CENTRAL STANISLAUS COUNTIES WILL EXPIRE AT 745 PM PDT... The storm which prompted the warning has moved out of the area. Therefore, the warning will be allowed to expire. A new Severe Thunderstorm Warning remains in effect for portions of Stanislaus and San Joaquin Counties until 815 PM PDT. LAT...LON 3748 12101 3753 12123 3780 12119 3768 12084 TIME...MOT...LOC 0240Z 201DEG 13KT 3765 12106 $$ NR
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sacramento, CA wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 9, 1:08 PM PDT, 6 hours 6 minutes earlier. Its key messages:
- Cooler temperatures and active weather today through the weekend with rain, strong to severe thunderstorms, gusty winds, and significant mountain snow
- Winter Storm Warning in effect for the Sierra and Southern Cascades Friday evening through Sunday evening
Area forecast discussion, Apr 9, 1:08 PM PDT, 6 hours 6 minutes before
Area Forecast Discussion National Weather Service Sacramento CA 108 PM PDT Thu Apr 9 2026 For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing. .KEY MESSAGES... - Cooler temperatures and active weather today through the weekend with rain, strong to severe thunderstorms, gusty winds, and significant mountain snow - Winter Storm Warning in effect for the Sierra and Southern Cascades Friday evening through Sunday evening && .DISCUSSION... ...Today through the Weekend... Current radar and satellite imagery show showers and thunderstorms starting to develop across far northern California, including the higher terrain of the Coast Range, Shasta County and southern Cascades. A pattern change is bringing cooler and wetter weather to the region today through the weekend. Temperatures are currently trending approximately 5 to 8 degrees cooler than this time yesterday. Forecast highs will be in the 50s to 60s in the mountains and 60s to around 80 in the Valley and foothills today, continuing to cool with highs in the 30s to 60s by the weekend. Scattered showers and thunderstorms will impact the area through the weekend as well. Latest forecast precipitation amounts have trended slightly higher than the previous forecast. Slick roads and minor travel delays can be expected from rain. The latest probability of thunder from the National Blend of Models indicated a 45-65% chance for today and Friday for thunderstorms across basically our entire forecast area. High resolution guidance depicts sufficient CAPE and shear values that could lead to severe hail (1.00+ inch), and also weak tornadoes or funnel clouds. These impacts will be in addition to the threat for brief heavy rain, gusty winds and lightning. Thunderstorm chances will also linger into Saturday and Sunday. When thunder roars, go indoors! The snow forecast has also trended slightly higher since the previous forecast. The Winter Storm Watch has been upgraded to a Winter Storm Warning from Friday evening through Sunday evening for elevations above 4500 feet. Snow levels will initially be at pass level or above on Friday, and will lower below the passes over the weekend. Heaviest snow rates and lowest snow levels are expected to be from Saturday afternoon through Sunday where major impacts to mountain travel are anticipated. Mountain travel is discouraged this weekend while the Warning is in effect. Gusty southerly winds are also forecast, with the strongest on Saturday. The north/central Sacramento Valley, northeast foothills and Sierra Crest will see the strongest winds. We will continue to montior the trends in the forecast to see if a product will be needed for the winds. ...Early Next Week... There may be some lingering showers mainly in the mountains on Monday. Otherwise drier and warmer weather is projected to return early to mid next week. Forecast highs will generally be in the 60s to 70s in the Valley and foothills. && .AVIATION... Primarily VFR conditions over the next 24 hours, except within thunderstorms through 09z Friday, and again between 18z Friday and 09z Saturday, which will bring potential for brief MVFR/IFR conditions in any heavy rainfall. Surface winds generally at or below 12 kt in the Valley through 12z Saturday, before southerly wind speeds begin to increase across interior NorCal and continue through late Saturday; gusts up to 35-45 mph in the Valley and up to 50 mph in the mountains at times. Gusty and erratic winds will occur near any thunderstorms as well. && .STO WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 5 PM Friday to 11 PM PDT Sunday for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park. &&
The office that day
Everything else NWS Sacramento, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 9, 5:01 PM PDT | Severe Thunderstorm Warning | STO | Shasta, Tehama | 29 min |
| Apr 9, 5:22 PM PDT | Severe Thunderstorm Warning | STO | Shasta | 38 min |
| Apr 9, 6:52 PM PDT | Severe Thunderstorm Warning | STO | San Joaquin, Stanislaus | 38 min |
| Apr 9, 7:39 PM PDT | Severe Thunderstorm Warning | STO | San Joaquin, Stanislaus | 36 min |
| Apr 10, 7:50 AM PDT | Severe Thunderstorm Warning | STO | Butte, Nevada, Plumas, Sierra, Yuba | 40 min |
| Apr 10, 1:55 PM PDT | Severe Thunderstorm Warning | STO | San Joaquin, Stanislaus | 35 min |
| Apr 10, 2:13 PM PDT | Severe Thunderstorm Warning | STO | Stanislaus | 15 min |
| Apr 10, 2:21 PM PDT | Tornado Warning | STO | San Joaquin, Stanislaus | 24 min |
| Apr 10, 2:38 PM PDT | Severe Thunderstorm Warning | STO | Stanislaus | 26 min |
| Apr 10, 2:40 PM PDT | Severe Thunderstorm Warning | STO | Calaveras, San Joaquin, Stanislaus | 35 min |
| Apr 10, 3:00 PM PDT | Severe Thunderstorm Warning | STO | Sacramento, San Joaquin, Solano, Yolo | 30 min |
| Apr 10, 4:08 PM PDT | Severe Thunderstorm Warning | STO | Calaveras, Tuolumne | 25 min |
Nearby
Severe Thunderstorm Warnings in California, 2026Every severe thunderstorm warning in 2026
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.