Alert archive / California / Winter Storm Warnings in 2018

Winter Storm Warning 6, NWS Reno, NV

March 20, 20185 counties in California; Douglas County, Washoe County, Nevada

NWS Reno, NV issued this winter storm warning at Mar 20, 2018, 12:49 PM PDT for 5 counties in California; Douglas County, Washoe County, Nevada. It took effect at Mar 21, 2018, 5:00 PM PDT. It was in force for 29 hr. 25 reports 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
Mar 20, 2018, 12:49 PM PDT (19:49 UTC)
In effect from
Mar 21, 2018, 5:00 PM PDT
Expired
Mar 22, 2018, 10:22 PM PDT
In force
29 hr
Issued by
NWS Reno, NV

Counties Alpine County, CA, El Dorado County, CA, Mono County, CA, Nevada County, CA, Placer County, CA, Douglas County, NV, Washoe County, NV

The radar

The Reno radar (KRGX), 92 km from the middle of the area, began a volume at 19:49 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

TimeReportWhereRemark
Mar 22, 7:00 AM PDTSNOW 1.5Sugar Pine Point S, CACOCORAHS STATION CA-ED-9, SUGAR PINE POINT S.
Mar 22, 7:00 AM PDTSNOW 1.5Tahoma, Ca, CACO-OP OBSERVER STATION TAAC1, TAHOMA, CA.
Mar 22, 7:00 AM PDTSNOW 64 N Spooner Summit, NVMESONET STATION MRLN2, 4 N SPOONER SUMMIT.
Mar 22, 7:00 AM PDTSNOW 81 Sw Alpine Meadows, CAALPINE MEADOWS REPORTED 8 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 7:00 AM PDTSNOW 111 Wsw Squaw Valley, CASQUAW VALLEY SKI RESORT REPORTED 11 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 7:00 AM PDTSNOW 141 Ssw Northstar, CANORTH STAR SKI ARE REPORTED 14 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 7:00 AM PDTSNOW 161 Ne Mount Rose Summit, NVMT. ROSE SKI AREA REPORTED 16 INCHES OF SNOW OVERNIGHT WITH A STORM TOTAL OF 21-25 IN THE LAST 36 HOURS.
Mar 22, 7:00 AM PDTSNOW 183 E Incline Village, NVDIAMOND PEAK SKI AREA REPORTED 18 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 7:00 AM PDTHEAVY SNOW 401 Ssw Mammoth Mountain, CAMAMMOTH MOUNTAIN SKI AREA REPORTED 40-48 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 8:00 AM PDTSNOW 37 Wsw Coleville, CAMESONET STATION XXXC1, 7 WSW COLEVILLE.
Mar 22, 8:00 AM PDTSNOW 8Mammoth Lakes R.S., CACO-OP OBSERVER STATION MALC1, MAMMOTH LAKES R.S.
Mar 22, 8:00 AM PDTSNOW 103 Wnw Grover Hot Spring, CAMESONET STATION BSKC1, 3 WNW GROVER HOT SPRINGS.
Mar 22, 8:00 AM PDTSNOW 193 Wsw Conway Summit, CAMESONET STATION VGAC1, 3 WSW CONWAY SUMMIT.
Mar 22, 9:00 AM PDTSNOW 2Dagget Pass, NVCO-OP OBSERVER STATION DAGN2, DAGGET PASS.
Mar 22, 9:00 AM PDTSNOW 2Meeks Bay, CAMESONET STATION RUBC1, MEEKS BAY.
Mar 22, 9:00 AM PDTSNOW 57 Wsw Coleville, CAMESONET STATION XXXC1, 7 WSW COLEVILLE.
Mar 22, 9:00 AM PDTSNOW 84 N Spooner Summit, NVMESONET STATION MRLN2, 4 N SPOONER SUMMIT.
Mar 22, 9:00 AM PDTSNOW 91 Sw Independence Lake, CAMESONET STATION ILKC1, 1 SW INDEPENDENCE LAKE.
Mar 22, 9:00 AM PDTSNOW 95 N Leavitt Meadows, CAMESONET STATION SDWC1, 5 N LEAVITT MEADOWS.
Mar 22, 9:00 AM PDTSNOW 9Sonora Pass, CAMESONET STATION SRAC1, SONORA PASS.
Mar 22, 9:00 AM PDTSNOW 112 Se Stateline, CAMESONET STATION HVNC1, 2 SE STATELINE.
Mar 22, 9:00 AM PDTSNOW 203 Wsw Conway Summit, CAMESONET STATION VGAC1, 3 WSW CONWAY SUMMIT.
Mar 22, 10:05 AM PDTSNOW 8Homewood, CAHOMEWOOD SKI AREA REPORTED 8 INCHES OF SNOW IN THE LAST 24 HOURS.
Mar 22, 3:02 PM PDTHEAVY SNOW 343 Nne Leavitt Meadows, CAMILITARY UNIT OPERATING AT 8400 FEET ABOVE THE MARINE CORPS MOUNTAIN WARFARE TRAINING CENTER RECEIVED 34 INCHES OF SNOW FROM 7 PM PDT 21 MARCH TO 1 PM PDT 22 MARCH. A MIX OF RAIN AND SNOW WAS REPORTED AT 6800 FEET AT THE MAIN BASE WITH AN ACCUMULATION OF 2-3 I
Mar 22, 7:49 PM PDTHEAVY SNOW 2.73 Wsw Gardnerville Ranc, NVTRAINED WEATHER SPOTTER REPORTED A STORM TOTAL 2.69 INCHES OF RAINFALL IN THE PAST 48 HOURS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Reno, NV (KREV), launched 12:00Z, 7.8 hours before the alert went out and 166 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.

Skew-T log-pSkew-T log-p diagram, Reno, NV at 12:00Z on 2018-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Reno, NV at 12:00Z on 2018-03-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 85 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1878 m above ground
0-6 km bulk shear
81 kt
0-1 km storm-relative helicity
85 m²/s²
0-3 km storm-relative helicity
337 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

418 
WWUS45 KREV 201949
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
1249 PM PDT Tue Mar 20 2018

CAZ072-NVZ002-211200-
/O.UPG.KREV.WS.A.0006.180322T0000Z-180323T1200Z/
/O.NEW.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
1249 PM PDT Tue Mar 20 2018

...WINTER STORM WARNING IN EFFECT FROM 5 PM WEDNESDAY TO 5 AM PDT
FRIDAY ABOVE 7000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 3
  feet mainly above 7500 feet, with localized amounts up to 4 feet
  or more near the Sierra Crest, are expected. 6 to 12 inches are
  likely down to 7000 feet, with localized amounts up to 18 inches
  west of Highway 89.

* WHERE...Greater Lake Tahoe Area.

* WHEN...From 5 PM Wednesday to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Gusty southwest to west winds near 45 mph
  are possible at times and may create periods of near whiteout
  conditions as well as choppy conditions on Lake Tahoe. Travel
  will be very difficult to impossible over the higher passes.
  Snow levels will fall to lake level by late Thursday night, but
  accumulations will be minimal. Damage to trees and power lines 
  is likely.
  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-211200-
/O.UPG.KREV.WS.A.0006.180322T0000Z-180323T1200Z/
/O.NEW.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
1249 PM PDT Tue Mar 20 2018

...WINTER STORM WARNING IN EFFECT FROM 5 PM WEDNESDAY TO 5 AM PDT
FRIDAY ABOVE 7500 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 4
  feet above 8000 feet, with localized amounts up to 5 feet or
  more near the Sierra Crest. Accumulations of 1 to 2 feet are
  likely down to 7500 feet, with 4 to 12 inches between 6500 and  
  7500 feet west of Highway 395.

* WHERE...Mono County.

* WHEN...From 5 PM Wednesday to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  especially over the higher passes along Highway 395. Gusty west
  to southwest winds of up to 40 mph may produce brief whiteout
  conditions. Damage to trees and power lines is likely. Snow
  levels will fall below 6500 feet late Thursday night, with
  minimal accumulations.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
8 follow-up statements
324 
WWUS45 KREV 211035
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
335 AM PDT Wed Mar 21 2018

CAZ072-NVZ002-220000-
/O.CON.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
335 AM PDT Wed Mar 21 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 5 AM PDT FRIDAY ABOVE 7000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 3
  feet mainly above 7500 feet, with localized amounts up to 4 feet
  near the Sierra Crest, are expected. 4 to 10 inches down to 
  7000 feet, with localized amounts up to 18 inches west of 
  Highway 89, are expected.

* WHERE...Greater Lake Tahoe Area above 7000 feet.

* WHEN...From 5 PM this afternoon to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Gusty southwest to west winds near 45 mph
  are possible at times and may create periods of near whiteout
  conditions as well as choppy conditions on Lake Tahoe. Travel
  will be very difficult to impossible over the higher passes.
  Snow levels will fall to lake level by late Thursday night, but
  accumulations will be minimal. Damage to trees and power lines 
  is likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-220000-
/O.CON.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
335 AM PDT Wed Mar 21 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 5 AM PDT FRIDAY ABOVE 7500 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 4
  feet mainly above 8500 feet, with localized amounts of 5 or more
  feet near the Sierra crest, are expected. 5 to 10 inches are
  expected down to 7500 feet.

* WHERE...Mono County above 7500 feet.

* WHEN...From 5 PM this afternoon to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  especially over the higher passes along Highway 395. Gusty west
  to southwest winds of up to 40 mph may produce brief whiteout
  conditions. Damage to trees and power lines is likely. Snow
  levels will fall below 6500 feet late Thursday night, with 2 to
  4 inches of snow accumulation likely west of Highway 395.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
150 
WWUS45 KREV 212022
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
122 PM PDT Wed Mar 21 2018

CAZ072-NVZ002-221200-
/O.CON.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
122 PM PDT Wed Mar 21 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 5 AM PDT FRIDAY ABOVE 7000 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 4
  feet mainly above 7500, with localized amounts up to 5 feet near
  the Sierra Crest, are expected. 4 to 12 inches down to 7000
  feet, with localized amounts up to 18 inches west of Highway 89,
  are expected. 

* WHERE...Greater Lake Tahoe Area.

* WHEN...From 5 PM this afternoon to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Gusty west to southwest winds near 40 mph 
  are possible at times and may create periods of near whiteout 
  conditions as well as choppy conditions on Lake Tahoe. Travel 
  will be very difficult to impossible over the higher passes. 
  Snow levels will fall to lake level by late Thursday night, but 
  accumulations will be minimal. Damage to trees and power lines 
  is likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-221200-
/O.CON.KREV.WS.W.0006.180322T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
122 PM PDT Wed Mar 21 2018

...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 PM THIS
AFTERNOON TO 5 AM PDT FRIDAY ABOVE 7500 FEET...

* WHAT...Heavy snow expected. Total snow accumulations of 2 to 4
  feet mainly above 8500 feet, with localized amounts of 5 or more
  feet near the Sierra Crest, are expected. 5 to 10 inches
  expected down to 7500 feet.

* WHERE...Mono County.

* WHEN...From 5 PM this afternoon to 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  especially over the higher passes along Highway 395. Gusty west
  to southwest winds of up to 40 mph may produce brief whiteout
  conditions. Damage to trees and power lines is likely. Snow
  levels will fall below 6500 feet late Thursday night, with 2 to
  4 inches of snow accumulation likely west of Highway 395.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
788 
WWUS45 KREV 221137
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
437 AM PDT Thu Mar 22 2018

CAZ072-NVZ002-230000-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
437 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7000 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 1
  to 3 feet, mainly above 7500 feet, with 4 to 12 inches down to
  7000 feet, are expected. At lake level, up to 4 inches of  
  snowfall is possible. 

* WHERE...Greater Lake Tahoe Area above 7000 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Gusty west to southwest winds near 40 mph
  are possible at times and may create periods of near whiteout
  conditions as well as choppy conditions on Lake Tahoe. Travel
  will be very difficult over the higher passes. Damage to trees 
  and power lines is likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-230000-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
437 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7500 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations 1 to
  4 feet mainly above 8500 feet, with 5-10 inches down to 7500
  feet, are expected. 

* WHERE...Mono County above 8000 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  especially over the higher passes along Highway 395. Gusty west
  to southwest winds of up to 40 mph may produce brief whiteout
  conditions. Damage to trees and power lines is likely.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
974 
WWUS45 KREV 221256
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
556 AM PDT Thu Mar 22 2018

CAZ072-NVZ002-230000-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
556 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 6500 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 8
  to 16 inches, with local amounts up to 2 feet near the Sierra
  Crest, are expected above 7000 feet. Up to 8 inches is expected
  between 6500 and 7000 feet, with a few slushy inches of 
  snowfall down to lake level.

* WHERE...Greater Lake Tahoe Area above 6500 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  especially over passes. Damage to trees and power lines is
  possible. Be prepared for significant reductions in visibility 
  at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-230000-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
556 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7500 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 1
  to 2 feet with localized amounts up to 3 feet near the Sierra
  Crest, are expected above 7500 feet. A light slushy accumulation
  is expected down to around 7000 feet.

* WHERE...Mono County above 7500 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions for
  passes and higher roads. Damage to trees and power lines is
  possible. Be prepared for significant reductions in visibility 
  at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ071-230000-
/O.NEW.KREV.WW.Y.0012.180322T1256Z-180323T0000Z/
Lassen-Eastern Plumas-Eastern Sierra Counties-
556 AM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON ABOVE 5500 FEET...

* WHAT...Snow occurring. Wet snow accumulations of 2 to 5 inches,
  with localized amounts up to 8 inches, are expected above 5500 
  feet.

* WHERE...Lassen-Eastern Plumas-Eastern Sierra Counties above 5500
  feet.

* WHEN...Until 5 PM PDT this afternoon.

* ADDITIONAL DETAILS...Plan on slushy and snow-covered roads for
  higher roads and passes, including Fredonyer Pass and Highway 44
  near Bogard, especially this morning. Damage to trees and power
  lines is possible. Be prepared for reduced visibilities at  
  times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
758 
WWUS45 KREV 221627
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
927 AM PDT Thu Mar 22 2018

CAZ072-NVZ002-230430-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
927 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 6500 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 6
  to 12 inches, with local amounts up to 2 feet near the Sierra
  Crest, are expected above 7000 feet. Up to 8 inches is expected
  between 6500 and 7000 feet, with a few slushy inches of 
  snowfall down to lake level.

* WHERE...Greater Lake Tahoe Area above 6500 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  especially over passes. Damage to trees and power lines is 
  possible. Be prepared for significant reductions in visibility 
  at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-230430-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
927 AM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7000 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 1
  to 2 feet with localized amounts up to 3 feet near the Sierra
  Crest, are expected above 7500 feet. 4 to 8 inches of heavy,
  slushy snow is expected down to 7000 feet.

* WHERE...Mono County above 7000 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions for 
  passes and higher roads. Damage to trees and power lines is 
  possible. Be prepared for significant reductions in visibility 
  at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ071-230000-
/O.CON.KREV.WW.Y.0012.000000T0000Z-180323T0000Z/
Lassen-Eastern Plumas-Eastern Sierra Counties-
927 AM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON ABOVE 5000 FEET...

* WHAT...Snow occurring. Wet snow accumulations of 2 to 6 inches,
  with localized amounts up to 9 inches, are expected above 5000 
  feet.

* WHERE...Lassen-Eastern Plumas-Eastern Sierra Counties above 5000
  feet.

* WHEN...Until 5 PM PDT this afternoon.

* ADDITIONAL DETAILS...Plan on slushy and snow-covered roads for
  higher roads and passes, including Fredonyer Pass and Highway 44
  near Bogard, especially this morning. Localized areas of slush
  are also likely on Highway 70 in Plumas County. Be prepared for
  reduced visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
236 
WWUS45 KREV 222111
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
211 PM PDT Thu Mar 22 2018

CAZ072-NVZ002-231200-
/O.NEW.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Truckee, Stateline, 
and Incline Village
211 PM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 6500 FEET...
...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM FRIDAY TO 5 AM
PDT SUNDAY...

* WHAT...Heavy snow occurring above 6500 feet. Snow expected.
  Above 6500 feet, additional snow accumulations of 5 to 8 inches,
  with localized amounts up to 12 inches, are expected. For the
  weekend storm...total snow accumulations of 8 to 12 inches, 
  with localized amounts up to 18 inches, are expected.

* WHERE...Greater Lake Tahoe Area.

* WHEN...For the Winter Storm Warning, until 5 AM PDT Friday. 
  For the Winter Weather Advisory, from 11 PM Friday to 5 AM PDT 
  Sunday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  including during the evening commutes. Damage to trees and 
  power lines is likely. Be prepared for significant reductions in
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-231200-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
211 PM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7000 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 3
  to 6 inches, with localized amounts up to 12 inches, are 
  expected.

* WHERE...Mono County above 7000 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the evening commute. Damage to trees and 
  power lines is likely. Be prepared for significant reductions 
  in visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ071-231200-
/O.NEW.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
/O.CON.KREV.WW.Y.0012.000000T0000Z-180323T0000Z/
Lassen-Eastern Plumas-Eastern Sierra Counties-
Including the cities of Portola and Susanville
211 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THIS
AFTERNOON ABOVE 5000 FEET...
...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM FRIDAY TO 5 AM
PDT SUNDAY...

* WHAT...Wet snow occurring above 5000 feet. Above 5000 feet,
  additional wet snow accumulations of up to 2 inches. For the
  weekend storm...total snow accumulations of 3 to 6 inches, with
  localized amounts up to 14 inches, are expected.

* WHERE...Lassen-Eastern Plumas-Eastern Sierra Counties.

* WHEN...For the Winter Weather Advisory, until 5 PM PDT this 
  afternoon. For the Winter Weather Advisory, from 11 PM Friday 
  to 5 AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on slippery road conditions, 
  including during the evening commute. Tree branches could 
  fall. Be prepared for reduced visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

CAZ070-231200-
/O.NEW.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
Surprise Valley California-
Including the cities of Cedarville and Fort Bidwell
211 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY IN EFFECT FROM 11 PM FRIDAY TO 5 AM
PDT SUNDAY...

* WHAT...Snow expected. Total snow accumulations of 2 to 5 inches
  are expected.

* WHERE...Surprise Valley California.

* WHEN...From 11 PM Friday to 5 AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions. Be 
  prepared for reduced visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
090 
WWUS45 KREV 230145
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
645 PM PDT Thu Mar 22 2018

CAZ072-NVZ002-231200-
/O.CAN.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
/O.CON.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Truckee, Stateline, and
Incline Village
645 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM FRIDAY TO
5 AM PDT SUNDAY...
...WINTER STORM WARNING FOR TONIGHT IS CANCELLED...

* WHAT...The threat for heavy snow has ended for tonight. For the
  weekend storm...total snow accumulations of 8 to 12 inches, 
  with localized amounts up to 18 inches, are expected.

* WHERE...Greater Lake Tahoe Area.

* WHEN...For the Winter Weather Advisory, from 11 PM Friday to 5
  AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions
  especially outside of daylight hours. Be prepared for 
  significant reductions in visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

CAZ073-231200-
/O.CON.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
Including the city of Mammoth Lakes
645 PM PDT Thu Mar 22 2018

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM PDT FRIDAY
ABOVE 7000 FEET...

* WHAT...Heavy snow occurring. Additional snow accumulations of 
  3 to 6 inches, with localized amounts up to 12 inches, are 
  expected.

* WHERE...Mono County above 7000 feet.

* WHEN...Until 5 AM PDT Friday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the evening commute. Damage to trees and 
  power lines is likely. Be prepared for significant reductions 
  in visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Avoid travel if possible, you could be stuck in your vehicle for
many hours. If you must travel, prepare for long delays and carry
an emergency kit with extra food, water and clothing. If you stay
home, have a backup plan in case of power outages. The latest
road conditions can be obtained by calling 5 1 1.

&&

$$

CAZ070-071-231200-
/O.CON.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
Surprise Valley California-Lassen-Eastern Plumas-
Eastern Sierra Counties-
Including the cities of Cedarville, Fort Bidwell, Portola, 
and Susanville
645 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM FRIDAY TO
5 AM PDT SUNDAY...

* WHAT...Wet snow occurring above 5000 feet. Above 5000 feet, 
  additional wet snow accumulations of up to 2 inches. For the 
  weekend storm...total snow accumulations of 3 to 6 inches, 
  with localized amounts up to 14 inches, are expected.

* WHERE...Lassen-Eastern Plumas-Eastern Sierra Counties.

* WHEN...For the Winter Weather Advisory, until 5 PM PDT this 
  afternoon. For the Winter Weather Advisory, from 11 PM Friday 
  to 5 AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on slippery road conditions, 
  including during the evening commute. Tree branches could 
  fall. Be prepared for reduced visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno
441 
WWUS45 KREV 230522
WSWREV

URGENT - WINTER WEATHER MESSAGE
National Weather Service Reno NV
1022 PM PDT Thu Mar 22 2018

CAZ073-230630-
/O.CAN.KREV.WS.W.0006.000000T0000Z-180323T1200Z/
Mono County-
1022 PM PDT Thu Mar 22 2018

...WINTER STORM WARNING IS CANCELLED...

Snow was ending across the eastern Sierra late this evening. The
threat for heavy snow has ended. Roads will remain icy where 
untreated and will be slick. Make sure to check chain and snow 
tire requirements before traveling Highway 395 tonight and early 
Friday.

$$

CAZ070-071-231200-
/O.CON.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
Surprise Valley California-Lassen-Eastern Plumas-
Eastern Sierra Counties-
Including the cities of Cedarville, Fort Bidwell, Portola, 
and Susanville
1022 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM FRIDAY TO
5 AM PDT SUNDAY...

* WHAT...Total snow accumulations of 3 to 6 inches, with 
  localized amounts up to 14 inches, are expected.

* WHERE...Lassen-Eastern Plumas-Eastern Sierra Counties.

* WHEN...For the Winter Weather Advisory, until 5 PM PDT this 
  afternoon. For the Winter Weather Advisory, from 11 PM Friday 
  to 5 AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on slippery road conditions, 
  including during the evening commute. Be prepared for reduced 
  visibilities at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

CAZ072-NVZ002-231200-
/O.CON.KREV.WW.Y.0013.180324T0600Z-180325T1200Z/
Greater Lake Tahoe Area-
Including the cities of South Lake Tahoe, Truckee, Stateline, 
and Incline Village
1022 PM PDT Thu Mar 22 2018

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 11 PM FRIDAY TO
5 AM PDT SUNDAY...

* WHAT...Total snow accumulations of 8 to 12 inches, with 
  localized amounts up to 18 inches, are expected.

* WHERE...Greater Lake Tahoe Area.

* WHEN...For the Winter Weather Advisory, from 11 PM Friday to 5 
  AM PDT Sunday.

* ADDITIONAL DETAILS...Plan on difficult travel conditions 
  especially outside of daylight hours. Be prepared for 
  significant reductions in visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Even light snowfall causes major travel delays, especially during
periods of high traffic volume. Be sure to allow extra time to
reach your destination. Leave extra space between vehicles since
it takes longer to stop on slick roadways. The latest road
conditions can be obtained by calling 5 1 1.

&&

$$

http://www.weather.gov/reno

What forecasters said that day

The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Reno, NV wrote its last area forecast discussion before this winter storm warning went out at Mar 20, 3:43 AM PDT, 9 hours 6 minutes earlier.

Area forecast discussion, Mar 20, 3:43 AM PDT, 9 hours 6 minutes before
Area Forecast Discussion
National Weather Service Reno NV
343 AM PDT Tue Mar 20 2018

.SYNOPSIS...

A period of light valley rain and higher elevation snow is expected
this evening and tonight. A much stronger atmospheric river type
storm pushes into the region Wednesday night through early Friday
morning. This will bring periods of heavy valley rain and heavy
Sierra snow along with gusty winds. The weekend will be colder
with snow showers possible down to all valley floors.

&&

.SHORT TERM...

Clouds will be on the increase today as a period of light valley
rain and higher elevation snow begins this evening and tonight.

However, the main focus in the short-term forecast is the incoming
Atmospheric River (AR) storm poised to provide multiple feet of high
elevation snowfall (Sierra cement) and periods of heavy rain to
lower valleys in the Sierra and western Nevada. Main change in the
forecast was to continue to increase expected precipitation totals
Wed-Thu.

*TIMING: Initial light to moderate precipitation with this storm
 begins on Wednesday in the Sierra but expecting the main period
 of heaviest precipitation to begin Wednesday night into early
 Thursday morning. Moderate to heavy precipitation continues
 Thursday afternoon before quickly diminishing Thursday night as a
 pronounced dry slot cuts off precipitation.

*SNOW LEVELS: AR storms are inherently warm systems as their
 moisture has tropical origins. As such, snow levels on Wednesday
 into Thursday morning will begin in the 7,500-8,500' range from
 the Tahoe Basin extending southward into Mono County. Snow levels
 will begin to drop in the late Thursday afternoon into evening
 time frame as the cold front nears. There is still some timing
 uncertainty on how quickly the front arrives but nonetheless,
 late Thursday afternoon-evening looks to be the period where
 travel deteriorates across most passes and snow will be possible
 at Lake Tahoe level and along portions of Hwy 395 through Mono
 County.

*RAIN/SNOW/HYDROLOGIC CONCERNS: This AR storm will provide heavy
 rains and high elevation snowfall Wed-Thu with most
 precipitation occurring Thursday. Overall, the main moisture
 plume will be concentrated through the Sierra in Mono County
 where 2-4 feet of snow will be possible above mainly 8,000' with
 localized areas up to 6 feet along the crest in southern Mono
 County. The Tahoe Basin will see up to 2-3 feet mainly above
 7,500' with localized areas up to 4 feet along the crest. Snow
 amounts below 7,500' are much lower confidence but generally
 6-12" are possible down to 7,000' feet with a few inches possible
 down to lake level by Thursday night.

This will be a rain event for western Nevada with moderate to heavy
rain expected on Thursday. 0.50-0.75" are possible across western
Nevada valleys. Rises on small creeks and streams can be expected
with some minor flooding possible in urban and poor drainage areas.

Minor flooding is also possible through the Sierra where snow has
not been removed to allow for drainage. There could also be rises on
small streams below 7000 feet that drain into the Tahoe basin and on
the east side of the Sierra. Although, main stem rivers do not look
like an issue, rises are expected on all rivers. The current
forecast takes the Middle Fork of the Feather River in Portola to
monitor stage, but at this point all other rivers are forecast to
remain below the point of concern. Fuentes

.LONG TERM...Friday onward...

The break in the precipitation between the warmer and colder
portions of the storms Friday morning is even more defined in latest
model guidance. Colder air moves into the region Friday as an upper
trough digs into northern CA/NV with a secondary cold frontal
boundary shifting through the region Friday night. This boundary
will provide the forcing to develop snow across the area with the
best chances in the Sierra, northeast California, and in western
Nevada mainly north of Highway 50. This is a fast moving feature and
there will only be a short period where the moisture and forcing
align, so am not expecting significant snow accumulations. However,
with snow levels at all valley floors, even light accumulations may
bring travel impacts across the region. A final passing shortwave
could bring one more chance for light snow showers Saturday night.
Considering we are getting into the latter part of March, most road
impacts from these lighter snows will be limited to the overnight
and early morning hours.

A warming and drying trend looks likely for next week, however
springtime is notorious for poor long range model guidance, so
nothing is a lock just yet. -Dawn

&&

.AVIATION...

Mid and high level clouds continue to stream into the region early
this morning, limiting the chances for fog formation. The one
exception is KTRK with patchy freezing fog through 16z this
morning.

A weak system will bring light rain and snow this afternoon and
evening with slightly lowered ceilings and terrain obscuration
possible. A much stronger storm is on tap for Wednesday and
Thursday with strong and gusty winds, and moderate to heavy
mountain snow and valley rain. Most precipitation should be
limited to the Sierra and northeast California on Wednesday, with
widespread spillover into western Nevada on Thursday. Terminals
should all just see rain, but expect widespread mountain
obscuration and periods of MVFR (30% chance IFR) ceilings and
visibility.

Winds will bring turbulence and wind shear, with local studies
indicating LLWS possible for KRNO Wednesday into Thursday. The
most likely periods for strongest valley winds will be Wednesday
and again Thursday afternoon. The period between will have heavy
precipitation which will dampen the wind speeds, however erratic
stronger gusts remain possible. Periods of snow showers are
possible for all airports Friday afternoon through Sunday morning
with the potential for minor accumulations, especially from 03z-
15z. -Dawn

&&

.REV Watches/Warnings/Advisories...
NV...Winter Storm Watch from Wednesday afternoon through late
     Thursday night above 7000 feet in NVZ002.

CA...Winter Storm Watch from Wednesday afternoon through late
     Thursday night above 7500 feet in CAZ073.

     Winter Storm Watch from Wednesday afternoon through late
     Thursday night above 7000 feet in CAZ072.

&&

For more information from the National Weather Service visit...
http://weather.gov/reno

The office that day

Everything else NWS Reno, NV issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 20, 12:49 PM PDTLake Wind AdvisoryREVAlpine, El Dorado, Nevada, Placer55 hr
Mar 20, 2:24 PM PDTFlood WatchREVAlpine, El Dorado, Lassen, Mono, Nevada, Placer and 2 more48 hr

Nearby

Winter Storm Warnings in California, 2018Winter Storm Warnings in Nevada, 2018Every winter storm warning in 2018

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.