Alert archive / Idaho / Winter Storm Warnings in 2021
Winter Storm Warning 8, NWS Boise, ID
NWS Boise, ID issued this winter storm warning at Dec 10, 2021, 2:26 PM MST for 7 counties in Idaho. It took effect at Dec 11, 2021, 5:00 AM MST. It was in force for 46 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
- Dec 10, 2021, 2:26 PM MST (21:26 UTC)
- In effect from
- Dec 11, 2021, 5:00 AM MST
- Expired
- Dec 13, 2021, 2:56 AM MST
- In force
- 46 hr
- Issued by
- NWS Boise, ID
Counties Adams County, ID, Boise County, ID, Camas County, ID, Elmore County, ID, Gem County, ID, Valley County, ID, Washington County, ID
The radar
The Boise radar (KCBX), 77 km from the middle of the area, began a volume at 21:24 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 12, 5:30 AM MST | HEAVY SNOW 13 | 11 Sse Horseshoe Bend, ID | BOGUS BASIN SKI SNOWSTAKE WEBCAM 6364 FT. |
| Dec 12, 5:32 AM MST | HEAVY SNOW 12 | 5 Sw Donnelly, ID | TAMARACK SKI SNOWSTAKE WEBCAM 6600 FT. |
| Dec 12, 5:34 AM MST | HEAVY SNOW 11 | Mccall, ID | MCCALL SNOWSTAKE WEBCAM 5030 FT. |
| Dec 12, 5:36 AM MST | HEAVY SNOW 19 | 5 Ne Meadows, ID | BRUNDAGE SKI SNOWSTAKE WEBCAM 6040 FT. |
| Dec 12, 5:39 AM MST | HEAVY SNOW 16 | 6 Wsw Warm Lake, ID | BIG CREEK SUMMIT NRCS SNOTEL 6560 FT. |
| Dec 12, 5:44 AM MST | HEAVY SNOW 11 | 9 W Featherville, ID | TRINITY MOUNTAIN NRCS SNOTEL 7770 FT. |
| Dec 12, 5:47 AM MST | HEAVY SNOW 12 | 9 Ese Pioneerville, ID | MORES CREEK SUMMIT NRCS SNOTEL 6100 FT. |
| Dec 12, 5:50 AM MST | HEAVY SNOW 14 | 21 E Deadwood Reservoir, ID | BANNER SUMMIT NRCS SNOTEL 7040 FT. |
| Dec 12, 5:53 AM MST | HEAVY SNOW 17 | 9 Se Warm Lake, ID | DEADWOOD SUMMIT NRCS SNOTEL 6860 FT. |
| Dec 12, 5:55 AM MST | HEAVY SNOW 13 | 15 W Cambridge, ID | BEAR SADDLE NRCS SNOTEL 6180 FT. |
| Dec 12, 5:56 AM MST | HEAVY SNOW 8 | 4 N Donnelly, ID | LONG VALLEY NRCS SNOTEL 4890 FT. |
| Dec 12, 5:58 AM MST | HEAVY SNOW 6 | 8 Se Anderson Dam, ID | CAMAS CREEK DIVIDE NRCS SNOTEL 5710 FT. |
| Dec 12, 5:59 AM MST | HEAVY SNOW 16 | 9 Ese Glendale, ID | SQUAW FLAT NRCS SNOTEL 6240 FT. |
| Dec 12, 6:45 AM MST | HEAVY SNOW 12 | Fruitvale, ID | |
| Dec 12, 9:00 AM MST | HEAVY SNOW 9.5 | 2 S Featherville, ID | 1 INCH FELL BY 8 P.M. SATURDAY, THEN 8.5 INCHES FELL 8 P.M. SATURDAY THROUGH 9 A.M. SUNDAY. |
| Dec 12, 9:30 AM MST | HEAVY SNOW 7 | Banks, ID | REPORT ON SOCIAL MEDIA. |
| Dec 12, 9:30 AM MST | HEAVY SNOW 7 | Lowman, ID | REPORT ON SOCIAL MEDIA. |
| Dec 12, 9:45 AM MST | HEAVY SNOW 16 | Cuprum, ID | REPORT ON SOCIAL MEDIA. |
| Dec 12, 9:45 AM MST | HEAVY SNOW 19.5 | 2 Nnw New Meadows, ID | COCORAHS OBSERVER REPORTED ON SOCIAL MEDIA. |
| Dec 12, 10:00 AM MST | HEAVY SNOW 7 | Fairfield, ID | REPORT ON SOCIAL MEDIA. |
| Dec 12, 10:15 AM MST | HEAVY SNOW 20 | 3 Ssw Donnelly, ID | REPORT ON SOCIAL MEDIA. |
| Dec 12, 10:45 AM MST | HEAVY SNOW 7 | 12 Ene Boise, ID | BOTTOM OF WILDERNESS RANCH AT 3300 FT MSL. SOCIAL MEDIA REPORT. |
| Dec 12, 10:52 AM MST | SNOW 5 | 12 Nne Boise, ID | COCORAHS 24 HOUR SNOW REPORT AS OF 730AM. |
| Dec 12, 10:52 AM MST | SNOW 8 | 9 Sse Mccall, ID | COCORAHS 24 HOUR SNOW REPORT AS OF 830 AM. |
| Dec 12, 10:52 AM MST | SNOW 8.6 | 3 Se Placerville, ID | COCORAHS 24 HOUR SNOW REPORT AS OF 730 AM. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Boise Airport, ID (KBOI), launched 12:00Z, 9.4 hours before the alert went out and 68 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
- 792 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km storm-relative helicity
- 149 m²/s²
- 0-3 km storm-relative helicity
- 188 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
467 WWUS45 KBOI 102126 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 226 PM MST Fri Dec 10 2021 IDZ011-013-111200- /O.UPG.KBOI.WS.A.0003.211211T1200Z-211215T0600Z/ /O.NEW.KBOI.WS.W.0008.211211T1200Z-211215T0600Z/ West Central Mountains-Boise Mountains- 226 PM MST Fri Dec 10 2021 ...WINTER STORM WARNING IN EFFECT FROM 5 AM SATURDAY TO 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 20 to 30 inches above 4000 feet MSL, with 3 to 4 feet over higher mountain passes. Total snow accumulations of 10 to 20 inches below 4000 feet MSL. Winds could gust as high as 35 mph, causing localized reductions in visibility. * WHERE...West Central Mountains and Boise Mountains zones. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration winter storm with multiple periods of heavy snow. The heaviest snow is expected Saturday through Sunday morning. There could be lulls in snowfall intensity during the day on Sunday and during the day on Monday. Additionally, snow levels will rise to around 4000 feet MSL on Sunday and 5000 feet MSL on Monday, limiting snowfall accumulation below these elevations on these days. Snow will fall at all elevations on Tuesday as a cold front moves through the area. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-111200- /O.UPG.KBOI.WS.A.0003.211211T1200Z-211215T0600Z/ /O.NEW.KBOI.WS.W.0008.211211T1200Z-211212T1200Z/ Upper Weiser River- 226 PM MST Fri Dec 10 2021 ...WINTER STORM WARNING IN EFFECT FROM 5 AM SATURDAY TO 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...From 5 AM Saturday to 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. The hazardous conditions could impact the morning or evening commute. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ028-111200- /O.UPG.KBOI.WS.A.0003.211211T1200Z-211215T0600Z/ /O.NEW.KBOI.WW.Y.0015.211211T1200Z-211215T0600Z/ Camas Prairie- 226 PM MST Fri Dec 10 2021 ...WINTER WEATHER ADVISORY IN EFFECT FROM 5 AM SATURDAY TO 11 PM MST TUESDAY... * WHAT...Snow expected. Total snow accumulations of 8 to 14 inches. * WHERE...Camas Prairie zone. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of snow. The heaviest snow is expected Saturday night. There could be lulls in snowfall during the day on Sunday and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-111200- /O.NEW.KBOI.WW.Y.0015.211211T1200Z-211212T1200Z/ Baker County- 126 PM PST Fri Dec 10 2021 ...WINTER WEATHER ADVISORY IN EFFECT FROM 4 AM SATURDAY TO 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...From 4 AM Saturday to 4 AM PST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
9 follow-up statements
330 WWUS45 KBOI 110510 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 1010 PM MST Fri Dec 10 2021 IDZ011-013-111400- /O.CON.KBOI.WS.W.0008.211211T1200Z-211215T0600Z/ West Central Mountains-Boise Mountains- 1010 PM MST Fri Dec 10 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 AM SATURDAY TO 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 20 to 30 inches above 4000 feet MSL, with 3 to 4 feet over higher mountain passes. Total snow accumulations of 10 to 20 inches below 4000 feet MSL. Winds could gust as high as 35 mph, causing localized reductions in visibility. * WHERE...West Central Mountains and Boise Mountains zones. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel may become very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration winter storm with multiple periods of heavy snow. The heaviest snow is expected Saturday through Sunday morning and again Monday night and Tuesday. There could be lulls Sunday afternoon and during the day on Monday. Additionally, snow levels will rise to around 4000 feet MSL on Sunday and 5000 feet MSL on Monday, limiting snowfall accumulation below these elevations on these days. Snow will fall at all elevations on Tuesday as a cold front moves through the area. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-111400- /O.CON.KBOI.WS.W.0008.211211T1200Z-211212T1200Z/ Upper Weiser River- 1010 PM MST Fri Dec 10 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 AM SATURDAY TO 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...From 5 AM Saturday to 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ028-111400- /O.CON.KBOI.WW.Y.0015.211211T1200Z-211215T0600Z/ Camas Prairie- 1010 PM MST Fri Dec 10 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 AM SATURDAY TO 11 PM MST TUESDAY... * WHAT...Snow expected. Total snow accumulations of 8 to 14 inches. * WHERE...Camas Prairie zone. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of snow. The heaviest snow is expected Saturday night and again Tuesday. There could be lulls in snowfall during the day on Sunday and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-111400- /O.CON.KBOI.WW.Y.0015.211211T1200Z-211212T1200Z/ Baker County- 910 PM PST Fri Dec 10 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 4 AM SATURDAY TO 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...From 4 AM Saturday to 4 AM PST Sunday. * IMPACTS...Travel could be very difficult. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
624 WWUS45 KBOI 110902 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 202 AM MST Sat Dec 11 2021 IDZ011-013-112200- /O.CON.KBOI.WS.W.0008.211211T1200Z-211215T0600Z/ West Central Mountains-Boise Mountains- 202 AM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 AM EARLY THIS MORNING TO 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 20 to 30 inches above 4000 feet MSL, with 3 to 4 feet over higher mountain passes. Total snow accumulations of 10 to 20 inches below 4000 feet MSL. Winds could gust as high as 35 mph, causing localized reductions in visibility. * WHERE...West Central Mountains and Boise Mountains zones. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel may become very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration winter storm with multiple periods of heavy snow. The heaviest snow is expected Saturday through Sunday morning and again Monday night and Tuesday. There could be lulls Sunday afternoon and during the day on Monday. Additionally, snow levels will rise to around 4000 feet MSL on Sunday and 5000 feet MSL on Monday, limiting snowfall accumulation below these elevations on these days. Snow will fall at all elevations on Tuesday as a cold front moves through the area. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-112200- /O.CON.KBOI.WS.W.0008.211211T1200Z-211212T1200Z/ Upper Weiser River- 202 AM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 5 AM EARLY THIS MORNING TO 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...From 5 AM Saturday to 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ028-112200- /O.CON.KBOI.WW.Y.0015.211211T1200Z-211215T0600Z/ Camas Prairie- 202 AM MST Sat Dec 11 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 5 AM EARLY THIS MORNING TO 11 PM MST TUESDAY... * WHAT...Snow expected. Total snow accumulations of 8 to 14 inches. * WHERE...Camas Prairie zone. * WHEN...From 5 AM Saturday to 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of snow. The heaviest snow is expected Saturday night and again Tuesday. There could be lulls in snowfall during the day on Sunday and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-112200- /O.CON.KBOI.WW.Y.0015.211211T1200Z-211212T1200Z/ Baker County- 102 AM PST Sat Dec 11 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 4 AM EARLY THIS MORNING TO 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...From 4 AM Saturday to 4 AM PST Sunday. * IMPACTS...Travel could be very difficult. * ADDITIONAL DETAILS...Light snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
768 WWUS45 KBOI 112119 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 219 PM MST Sat Dec 11 2021 IDZ028-120600- /O.UPG.KBOI.WW.Y.0015.000000T0000Z-211215T0600Z/ /O.EXA.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ Camas Prairie- 219 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 12 to 18 inches. * WHERE...Camas Prairie zone. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall tonight into Sunday morning, but additional periods of heavy snow will occur through Tuesday. There could be lulls Sunday afternoon and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ011-013-120600- /O.CON.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains- 219 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 20 to 30 inches above 4000 feet MSL, with 3 to 4 feet over higher mountain passes. Total snow accumulations of 10 to 20 inches below 4000 feet MSL. Winds could gust as high as 35 mph, causing localized reductions in visibility. * WHERE...Boise Mountains and West Central Mountains zones. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration winter storm with multiple periods of heavy snow. The heaviest snow is expected tonight through Sunday morning, although there will be additional periods of heavy snow through Tuesday. There could be lulls Sunday afternoon and during the day on Monday. Additionally, snow levels will rise to around 4000 feet MSL on Sunday and 5000 feet MSL on Monday, limiting snowfall accumulation below these elevations on these days. Snow will fall at all elevations on Tuesday as a cold front moves through the area. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-120600- /O.CON.KBOI.WS.W.0008.000000T0000Z-211212T1200Z/ Upper Weiser River- 219 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...Until 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-120600- /O.CON.KBOI.WW.Y.0015.000000T0000Z-211212T1200Z/ Baker County- 119 PM PST Sat Dec 11 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...Until 4 AM PST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
436 WWUS45 KBOI 120510 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 1010 PM MST Sat Dec 11 2021 IDZ011-013-028-121400- /O.CON.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains-Camas Prairie- 1010 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 12 to 18 inches. * WHERE...Camas Prairie zone. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall tonight into Sunday morning, and again Monday night and Tuesday morning as a cold front moves through. There could be lulls Sunday afternoon and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-121200- /O.CON.KBOI.WS.W.0008.000000T0000Z-211212T1200Z/ Upper Weiser River- 1010 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...Until 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-121200- /O.CON.KBOI.WW.Y.0015.000000T0000Z-211212T1200Z/ Baker County- 910 PM PST Sat Dec 11 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...Until 4 AM PST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
216 WWUS45 KBOI 120515 CCA WSWBOI URGENT - WINTER WEATHER MESSAGE...CORRECTED National Weather Service Boise ID 1015 PM MST Sat Dec 11 2021 IDZ011-013-028-121400- /O.COR.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains-Camas Prairie- 1015 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 12 to 18 inches at lower pass levels, and up to 3 to 4 feet at higher passes and upper slopes. * WHERE...Camas Prairie and Idaho mountains north of the Snake Basin zone. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall tonight into Sunday morning, and again Monday night and Tuesday morning as a cold front moves through. There could be lulls Sunday afternoon and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ IDZ033-121200- /O.CON.KBOI.WS.W.0008.000000T0000Z-211212T1200Z/ Upper Weiser River- 1015 PM MST Sat Dec 11 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 AM MST SUNDAY... * WHAT...Heavy snow expected. Total snow accumulations of 5 to 10 inches, with up to 18 inches above 4000 feet MSL. * WHERE...Upper Weiser River zone. * WHEN...Until 5 AM MST Sunday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$ ORZ062-121200- /O.COR.KBOI.WW.Y.0015.000000T0000Z-211212T1200Z/ Baker County- 915 PM PST Sat Dec 11 2021 ...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 4 AM PST SUNDAY... * WHAT...Snow expected. Total snow accumulations of 3 to 6 inches, except 8 to 16 inches over the mountains. Baker City will see snowfall of 1 to 2 inches. Winds gusting as high as 35 mph. * WHERE...Baker County zone. * WHEN...Until 4 AM PST Sunday. * IMPACTS...Travel could be very difficult. * ADDITIONAL DETAILS...Snow will continue to fall above 4000 feet on Sunday and Monday, but additional impacts will be minor. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
791 WWUS45 KBOI 121141 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 441 AM MST Sun Dec 12 2021 IDZ033-121245- /O.EXP.KBOI.WS.W.0008.000000T0000Z-211212T1200Z/ Upper Weiser River- 441 AM MST Sun Dec 12 2021 ...WINTER STORM WARNING WILL EXPIRE AT 5 AM MST EARLY THIS MORNING... Snow will transition to rain as snow levels rise above 3500 feet MSL. Precipitation intensities will also decrease today. Light snow will return early Tuesday morning. $$ ORZ062-121245- /O.EXP.KBOI.WW.Y.0015.000000T0000Z-211212T1200Z/ Baker County- 341 AM PST Sun Dec 12 2021 ...WINTER WEATHER ADVISORY WILL EXPIRE AT 4 AM PST EARLY THIS MORNING... Precipitation intensities will decrease over Baker County today. Periods of light mountain snow and valley rain and snow will continue through Tuesday. $$ IDZ011-013-028-122200- /O.CON.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains-Camas Prairie- 441 AM MST Sun Dec 12 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow expected. Total snow accumulations of 12 to 18 inches at lower pass levels, and up to 3 to 4 feet at higher passes and upper slopes. * WHERE...Camas Prairie and the Idaho mountains north of the Snake Basin. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall through this morning, and again Monday night and Tuesday morning as a cold front moves through. There could be lulls this afternoon and during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$
414 WWUS45 KBOI 122123 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 223 PM MST Sun Dec 12 2021 IDZ011-013-028-130600- /O.CON.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains-Camas Prairie- 223 PM MST Sun Dec 12 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow. Additional snow accumulations of 4 to 8 inches above 4500 feet, and 1 to 2 feet at higher passes and upper slopes. * WHERE...Camas Prairie, West Central Mountains and Boise Mountains zones. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall Monday night and Tuesday morning as a cold front moves through. Snow levels tonight will be near 4500 feet and will rise to 5000-5500 feet on Monday, limiting snow accumulation below these elevations ahead of the cold front. There could be lulls during the day on Monday. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$
546 WWUS45 KBOI 130509 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 1009 PM MST Sun Dec 12 2021 IDZ011-013-028-131400- /O.CON.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ West Central Mountains-Boise Mountains-Camas Prairie- 1009 PM MST Sun Dec 12 2021 ...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST TUESDAY... * WHAT...Heavy snow. Additional snow accumulations of 4 to 8 inches above 4500 feet, and 1 to 2 feet at higher passes and upper slopes. * WHERE...Camas Prairie, West Central Mountains and Boise Mountains zones. * WHEN...Until 11 PM MST Tuesday. * IMPACTS...Travel could be very difficult to impossible. * ADDITIONAL DETAILS...This is a long duration snow event with multiple periods of heavy snow. The heaviest snow will fall Monday night and Tuesday morning as a cold front moves through. Snow levels tonight will be near 4500 feet and rise to 5000- 5500 feet on Monday ahead of the approaching cold front. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. The latest road conditions can be obtained by calling 5 1 1. && $$
122 WWUS45 KBOI 130956 WSWBOI URGENT - WINTER WEATHER MESSAGE National Weather Service Boise ID 256 AM MST Mon Dec 13 2021 IDZ011-013-028-132200- /O.CAN.KBOI.WS.W.0008.000000T0000Z-211215T0600Z/ /O.NEW.KBOI.WW.Y.0016.211213T0956Z-211215T0000Z/ West Central Mountains-Boise Mountains-Camas Prairie- 256 AM MST Mon Dec 13 2021 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST TUESDAY... ...WINTER STORM WARNING IS CANCELLED... * WHAT...Snow. Additional snow accumulations of 2 to 6 inches below 6000 feet, with 10 to 18 inches over elevations above 6000 feet including high mountain passes. Winds gusting up to 35 mph. * WHERE...West Central Mountains, Boise Mountains and Camas Prairie zones in Idaho. * WHEN...Until 5 PM MST Tuesday. * IMPACTS...Travel could be very difficult. * ADDITIONAL DETAILS...Rising snow levels today will reduce snow accumulations for elevations below 6000 feet through tonight. A cold front will arrive tonight through Tuesday morning, lowering snow levels back down to valley floors. The period of heaviest snowfall will occur with the cold front. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. The latest road conditions can be obtained by calling 5 1 1. && $$
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 Boise, ID wrote its last area forecast discussion before this winter storm warning went out at Dec 10, 10:13 AM MST, 4 hours 13 minutes earlier.
Area forecast discussion, Dec 10, 10:13 AM MST, 4 hours 13 minutes before
Area Forecast Discussion
National Weather Service Boise ID
1013 AM MST Fri Dec 10 2021
.DISCUSSION...Scattered snow showers will continue over the
mountains today under moist northwest flow aloft with minimal
accumulation. Models remain consistent in showing a powerful upper
trough shifting south off the coast today, ushering an atmospheric
river into our forecast area this weekend into early next week.
Models continue to depict heavy mountain snow during this time,
and the Winter Storm Watch will likely be upgraded later today.
In the lower elevations, precipitation totals will be much lower
due to strong southwest flow aloft and rain shadowing.
Precipitation will likely start out as snow on Saturday at lower
elevations and then change over to rain Saturday afternoon or
Saturday night. Models disagree on how soon temperatures warm
enough to change over to rain on Saturday. Very dry low levels due
to downsloping and evaporational cooling may aid in a slower
changeover. However, hi-resolution models generally depict
precipitation amounts through Saturday night around a tenth of an
inch or less in the Snake River Basin, greatly limiting snow
accumulation and associated impacts. Current forecast handles this
and no updates expected this morning.
&&
.AVIATION...Mostly cloudy. Isolated snow showers through 18z.
Another round of snow showers will move into southeast Oregon around
11/06Z. Areas of mountain obscuration and local MVFR/IFR ceilings in
snow. Surface winds: W to NW 10-20 kt with gusts to 25 kt in the
Magic Valley, SW-SE 5-10 kt northwest of the Magic Valley. Winds
aloft at 10k feet MSL: W to NW 25-45 kt.
Weekend Outlook..Widespread mountain snow developing Saturday
morning and continuing through Sunday, heaviest northeast of the
Snake River Plain and in high elevations of southeast Oregon. Lower
valleys will see precipitation start as snow Saturday but could
change over to rain in the afternoon. Mountain obscuration and areas
of MVFR/IFR in snow. Breezy winds overnight Saturday into early
Sunday morning, especially near higher elevations.
&&
.PREV DISCUSSION...
SHORT TERM...Today through Sunday night...Isolated snow showers
are diminishing this morning after leaving behind light snowfall
accumulations in their wake. Cold and drier northwest flow is
anticipated today. Winds will begin to increase tonight ahead of
the major atmospheric river event to arrive on Saturday. Snow
levels will initially be low enough that valleys could see light
snowfall as this system moves over the area on Saturday. However,
the strong southwest flow aloft will aid in limiting
precipitation totals for valley locations. Meanwhile, the
favorable orographic dynamics will ensure the mountains of west-
central/southwest Idaho and east-central Oregon receive
significant, widespread snowfall over multiple days, with
heaviest snowfall rates to occur on Saturday while snow levels
remain low. Snow levels will gradually rise to 3500-4500 feet MSL
on Sunday, with valley precipitation transitioning to rain or a
rain/snow mix. Overall, snow total accumulations of 1 to 2 feet
are possible over the weekend period for the Baker County, west-
central Idaho, and Boise Mountains. In addition, winds will be
breezy, creating blowing and drifting snow. Very challenging
travel conditions in the mountains can be expected and should be
avoided.
LONG TERM...Monday through Friday...An atmospheric river will
continue over the area early Monday, bringing widespread and
long-lasting precipitation to the region. Southwest flow will
keep temperatures above normal and breezy winds ahead of the upper
level trough axis passage on Wednesday. Several rounds of heavier
precipitation with this system are expected to bring a valley
rain/snow mix turning to rain and high elevation snow. Snow levels
will decrease from 4500-5000 feet MSL on Monday to 2500-3000 feet
MSL overnight on Wednesday. Upslope enhancements will increase
snowfall totals in the Central and Boise Mountains of Idaho, and
the Wallowa Mountains of Oregon. Significant snowfall is expected
with storm totals of 1-3 feet of snow above 5000 feet in these
areas. Please see our Winter Storm Watch product for more details.
Breezy winds will accompany this system Tuesday morning into
Wednesday. The upper level trough associated with the atmospheric
river should pass by Wednesday evening, bringing colder
temperatures and brief dry conditions ahead of another upper level
trough entering the area on Thursday. Model uncertainty remains
on the exact timing and location of this system, but there is
agreement on isolated snow showers throughout southeast Oregon and
southwest Idaho on Friday.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Winter Storm Watch from late tonight through Tuesday evening
IDZ011-013-028-033.
OR...None.
&&
www.weather.gov/Boise
www.facebook.com/NWSBoise
www.twitter.com/NWSBoise
DISCUSSION...ST
AVIATION.....JS
PREV SHORT TERM...SH
PREV LONG TERM....SAIn the hours before
Local storm report, Dec 10, 10:19 AM MST, 4 hours 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOISE ID
1019 AM MST FRI DEC 10 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 AM SNOW 2 NNW NEW MEADOWS 45.00N 116.30W
12/10/2021 M1.7 INCH ADAMS ID COCORAHS
COCORAHS STATION ID-AM-3 NEW MEADOWS 2.1
NNW.
0600 AM SNOW 4 ESE MEADOWS 44.93N 116.18W
12/10/2021 M1.2 INCH ADAMS ID COCORAHS
COCORAHS STATION ID-AM-2 MCCALL 3.6 WNW.
0700 AM SNOW 20 SE BOISE 43.39N 115.97W
12/10/2021 M1.0 INCH ELMORE ID COCORAHS
COCORAHS STATION ID-EL-11 MOUNTAIN HOME 22.3
NW.
0700 AM SNOW 5 SSE MERIDIAN 43.55N 116.35W
12/10/2021 M0.8 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-45 MERIDIAN 4.8 SSE.
0700 AM SNOW 4 SE MERIDIAN 43.56N 116.36W
12/10/2021 M0.8 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-27 MERIDIAN 3.9 SE.
0700 AM SNOW 1 ENE MIDDLETON 43.71N 116.61W
12/10/2021 M0.5 INCH CANYON ID COCORAHS
COCORAHS STATION ID-CY-12 MIDDLETON 0.7 ENE.
0700 AM SNOW 3 WSW GARDEN CITY 43.62N 116.30W
12/10/2021 M0.5 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-5 BOISE 4.4 WNW.
0700 AM SNOW 5 SE MERIDIAN 43.57N 116.32W
12/10/2021 M0.5 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-11 BOISE 6.1 SW.
0800 AM SNOW HAMMETT 42.95N 115.47W
12/10/2021 M0.5 INCH ELMORE ID COCORAHS
COCORAHS STATION ID-EL-5 HAMMETT 2.0 W.
0907 AM SNOW 3 ESE FILER 42.54N 114.55W
12/10/2021 M0.5 INCH TWIN FALLS ID COCORAHS
COCORAHS STATION ID-TF-1 TWIN FALLS 4.9 WSW.
0545 AM SNOW 6 SE BOISE 43.55N 116.13W
12/10/2021 M0.4 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-21 BOISE CITY 6.1 SE.
0830 AM SNOW MOUNTAIN HOME 43.13N 115.70W
12/10/2021 M0.4 INCH ELMORE ID COCORAHS
COCORAHS STATION ID-EL-3 MOUNTAIN HOME 0.9
SW.
0630 AM SNOW 1 N BOISE 43.63N 116.20W
12/10/2021 M0.3 INCH ADA ID COCORAHS
COCORAHS STATION ID-AD-9 BOISE 2.1 NNE.
0700 AM SNOW 2 N GLENNS FERRY 42.98N 115.30W
12/10/2021 M0.3 INCH ELMORE ID COCORAHS
COCORAHS STATION ID-EL-1 GLENNS FERRY 1.6 N.
0700 AM SNOW 4 ESE CALDWELL 43.65N 116.59W
12/10/2021 M0.3 INCH CANYON ID COCORAHS
COCORAHS STATION ID-CY-15 NAMPA 4.8 NNW.
0800 AM SNOW 6 WSW HINES 43.53N 119.19W
12/10/2021 M0.3 INCH HARNEY OR COCORAHS
COCORAHS STATION OR-HY-5 HINES 6.2 WSW.
0700 AM SNOW 1 NE MURPHY HOT SPRINGS 42.03N 115.35W
12/10/2021 M0.2 INCH OWYHEE ID CO-OP OBSERVER
CO-OP OBSERVER STATION MHSI1 MURPHY HOT
SPRINGS.
0700 AM SNOW 6 W KUNA 43.48N 116.53W
12/10/2021 M0.1 INCH CANYON ID COCORAHS
COCORAHS STATION ID-CY-30 NAMPA 7.2 SSE.
0800 AM SNOW 1 ENE BAKER 44.78N 117.82W
12/10/2021 M0.1 INCH BAKER OR COCORAHS
COCORAHS STATION OR-BK-20 BAKER 0.5 ENE.
&&The office that day
Everything else NWS Boise, ID issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 10, 2:26 PM MST | Winter Weather Advisory | BOI | Camas, Elmore | 39 hr |
Nearby
Winter Storm Warnings in Idaho, 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.