Alert archive / California / Winter Storm Warnings in 2021
Winter Storm Warning 5, NWS San Diego, CA
NWS San Diego, CA issued this winter storm warning at Dec 23, 2021, 10:03 PM PST for Riverside County, San Bernardino County, California. It was in force for 14 hr. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Dec 23, 2021, 10:03 PM PST (06:03 UTC)
- Expired
- Dec 24, 2021, 12:00 PM PST
- In force
- 14 hr
- Issued by
- NWS San Diego, CA
The radar
The Santa Ana Mts radar (KSOX), 152 km from the middle of the area, began a volume at 06:05 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Dec 23, 10:46 PM PST | SNOW 3 | 10 Se Big Bear City, CA | CALTRANS REPORTS SEVERAL VEHICLES STUCK IN THE SNOW ON SR-38 NEAR RAINBOW LN. AROUND 8,000 FT ELEVATION. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
San Diego, CA (KNKX), launched 00:00Z, 6.1 hours before the alert went out and 195 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
- 1578 m above ground
- 0-6 km bulk shear
- 86 kt
- 0-1 km storm-relative helicity
- 157 m²/s²
- 0-3 km storm-relative helicity
- 142 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
818 WWUS46 KSGX 240603 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 1003 PM PST Thu Dec 23 2021 CAZ055-056-241415- /O.UPG.KSGX.WW.Y.0009.211224T0800Z-211224T2000Z/ /O.NEW.KSGX.WS.W.0005.211224T0603Z-211224T2000Z/ San Bernardino County Mountains-Riverside County Mountains- 1003 PM PST Thu Dec 23 2021 ...WINTER STORM WARNING IN EFFECT UNTIL NOON PST FRIDAY ABOVE 7000 FEET... * WHAT...Heavy wet snow occurring. Travel will be very difficult to impossible. Damage to trees and power lines is possible. Additional wet snow accumulations of 10 to 16 inches, with localized amounts up to 32 inches above 8500 feet, are expected. * WHERE...Mountains above 7000 feet. Lighter accumulations down to about 6500 feet. * WHEN...Until noon Friday. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for wet snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$ 17
2 follow-up statements
247 WWUS46 KSGX 241119 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 319 AM PST Fri Dec 24 2021 CAZ055-056-242000- /O.CON.KSGX.WS.W.0005.000000T0000Z-211224T2000Z/ San Bernardino County Mountains-Riverside County Mountains- 319 AM PST Fri Dec 24 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL NOON PST TODAY ABOVE 7000 FEET... * WHAT...Heavy wet snow occurring. Travel will be very difficult to impossible. Damage to trees and power lines is possible. Additional wet snow accumulations of 8 to 12 inches, with localized amounts up to 16 inches above 8500 feet, are expected. * WHERE...Mountains above 7000 feet. Lighter accumulations down to about 6500 feet. * WHEN...Until noon today. * ADDITIONAL DETAILS...Be prepared for significant reductions in visibility at times. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Warning for wet snow means severe winter weather conditions are occurring. If you must travel, keep an extra flashlight, food and water in your vehicle in case of an emergency. For road condition information in California...enter 8 0 0 4 2 7 7 6 2 3 if inside california or 9 1 6 4 5 5 7 6 2 3 if outside California. $$ 17
714 WWUS46 KSGX 242000 WSWSGX URGENT - WINTER WEATHER MESSAGE National Weather Service SAN DIEGO CA 1200 PM PST Fri Dec 24 2021 ...NEXT STORM SYSTEM TO BRING SNOW TO THE SAN BERNARDINO AND RIVERSIDE COUNTY MOUNTAINS SATURDAY NIGHT AND SUNDAY MORNING... CAZ055-056-250600- /O.EXP.KSGX.WS.W.0005.000000T0000Z-211224T2000Z/ /O.NEW.KSGX.WS.A.0005.211226T0200Z-211226T1800Z/ San Bernardino County Mountains-Riverside County Mountains- Including the cities of Crestline, Lake Arrowhead, Big Bear City, Big Bear Lake, Running Springs, Wrightwood, and Idyllwild-Pine Cove 1200 PM PST Fri Dec 24 2021 ...WINTER STORM WATCH IN EFFECT FROM SATURDAY EVENING THROUGH SUNDAY MORNING... ...WINTER STORM WARNING WILL EXPIRE AT NOON PST TODAY ABOVE 7000 FEET... * WHAT...Heavy snow possible. Plan on difficult travel conditions. Tree branches could fall as well. Total snow accumulations of 3 to 6 inches Saturday night and Sunday morning, with localized amounts up to 12 inches, are possible. * WHERE...San Bernardino and Riverside County Mountains. * WHEN...From Saturday evening through Sunday morning. * ADDITIONAL DETAILS...Significant reductions in visibility are possible. Snow level will be mostly be around 5000 feet with this storm. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Winter Storm Watch means there is potential for significant snow, sleet or ice accumulations that may impact travel. Continue to monitor the latest forecasts. $$ Maxwell
The office that day
Everything else NWS San Diego, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 23, 5:29 PM PST | Areal Flood Advisory | SGX | Riverside, San Bernardino | 3 hr |
| Dec 23, 8:01 PM PST | Areal Flood Advisory | SGX | Orange | 7 hr |
| Dec 23, 8:20 PM PST | Areal Flood Advisory | SGX | Riverside, San Bernardino | 7 hr |
| Dec 23, 9:31 PM PST | Areal Flood Advisory | SGX | San Diego | 3 hr |
| Dec 24, 1:17 AM PST | Flash Flood Warning | SGX | Riverside, San Bernardino | 3 hr |
| Dec 24, 2:26 AM PST | Areal Flood Advisory | SGX | San Diego | 3 hr |
| Dec 24, 6:14 AM PST | Beach Hazards Statement | SGX | Orange, San Diego | 2 hr |
| Dec 24, 7:07 AM PST | Areal Flood Advisory | SGX | Orange, Riverside, San Bernardino, San Diego | 2 hr |
| Dec 24, 7:31 AM PST | Areal Flood Advisory | SGX | San Diego | 90 min |
| Dec 24, 12:00 PM PST | Winter Storm Watch | SGX | Riverside, San Bernardino | 9 hr |
Nearby
Winter Storm Warnings in California, 2021Every winter storm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.