Cheyenne, Wyoming
Regional Weather Alerts
| Alert: | Freeze Watch |
| Area(s): | South Laramie Range |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-19 @ 10:00 pm -> 2026-05-20 @ 11:00 am |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Watch issued May 18 at 1:00PM MDT until May 20 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 12 above expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 23 possible. * WHERE...South Laramie Range. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Upper North Platte River Basin |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-19 @ 1:00 am -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 18 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 20 possible. * WHERE...Upper North Platte River Basin. * WHEN...For the Freeze Warning, from midnight tonight to 10 AM MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Central Laramie Range and Southwest Platte County; South Laramie Range Foothills; Central Laramie County; East Laramie County |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 9:00 pm -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Sub-freezing temperatures as low as 20 expected. * WHERE...Central Laramie County, Central Laramie Range and Southwest Platte County, East Laramie County, and South Laramie Range Foothills. * WHEN...From 8 PM this evening to 10 AM MDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Scotts Bluff; North Sioux; South Sioux; Niobrara County; East Platte County; Goshen County |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 9:00 pm -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Sub-freezing temperatures as low as 21 expected. * WHERE...In Nebraska, Northern Sioux County, Scotts Bluff County, and Southern Sioux County. In Wyoming, Niobrara County, East Platte County, and Goshen County. * WHEN...From 8 PM this evening to 10 AM MDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | South Laramie Range |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 9:00 pm -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 12 above expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 23 possible. * WHERE...South Laramie Range. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Converse County Lower Elevations |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 9:00 pm -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 16 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 23 possible. * WHERE...Converse County Lower Elevations. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from late Tuesday night through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Laramie Valley |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 9:00 pm -> 2026-05-19 @ 11:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 17 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 26 possible. * WHERE...Laramie Valley. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from late Tuesday night through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Warning |
| Area(s): | Ferris/Seminoe/Shirley Mountains; Shirley Basin; Central Carbon County; North Snowy Range Foothills; Southwest Carbon County |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-18 @ 7:00 pm -> 2026-05-19 @ 1:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Warning issued May 18 at 1:00PM MDT until May 19 at 12:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 12 above expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 18 possible. * WHERE...Central Carbon County, Ferris/Seminoe/Shirley Mountains, North Snowy Range Foothills, Shirley Basin, and Southwest Carbon County. * WHEN...For the Freeze Warning, from 6 PM this evening to noon MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Watch |
| Area(s): | Laramie Valley |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-20 @ 1:00 am -> 2026-05-20 @ 9:00 am |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Watch issued May 18 at 1:00PM MDT until May 20 at 8:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 17 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 26 possible. * WHERE...Laramie Valley. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from late Tuesday night through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Watch |
| Area(s): | Converse County Lower Elevations |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-20 @ 1:00 am -> 2026-05-20 @ 9:00 am |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Watch issued May 18 at 1:00PM MDT until May 20 at 8:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 16 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 23 possible. * WHERE...Converse County Lower Elevations. * WHEN...For the Freeze Warning, from 8 PM this evening to 10 AM MDT Tuesday. For the Freeze Watch, from late Tuesday night through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Watch |
| Area(s): | Ferris/Seminoe/Shirley Mountains; Shirley Basin; Central Carbon County; North Snowy Range Foothills; Southwest Carbon County |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-19 @ 10:00 pm -> 2026-05-20 @ 11:00 am |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Watch issued May 18 at 1:00PM MDT until May 20 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 12 above expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 18 possible. * WHERE...Central Carbon County, Ferris/Seminoe/Shirley Mountains, North Snowy Range Foothills, Shirley Basin, and Southwest Carbon County. * WHEN...For the Freeze Warning, from 6 PM this evening to noon MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Freeze Watch |
| Area(s): | Upper North Platte River Basin |
| Effective: | 2026-05-18 @ 2:00 pm -> 2026-05-19 @ 7:00 am |
| Onset: | 2026-05-19 @ 10:00 pm -> 2026-05-20 @ 11:00 am |
| Severity: | Severe |
| Certainty: | Possible |
| Urgency: | Future |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 2:00 pm |
| Headline: | Freeze Watch issued May 18 at 1:00PM MDT until May 20 at 10:00AM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...For the Freeze Warning tonight, sub-freezing temperatures as low as 18 expected. For the Freeze Watch Tuesday night, sub-freezing temperatures as low as 20 possible. * WHERE...Upper North Platte River Basin. * WHEN...For the Freeze Warning, from midnight tonight to 10 AM MDT Tuesday. For the Freeze Watch, from Tuesday evening through Wednesday morning. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Winter Storm Warning |
| Area(s): | Lander Foothills |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Snow expected. Additional snow accumulations up to 2 inches. * WHERE...Lander Foothills. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be difficult. Heavy snow could break tree limbs as many trees have leafed out. |
| Alert: | Winter Storm Warning |
| Area(s): | East Sweetwater County |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Heavy snow expected. Additional snow accumulations between 1 and 3 inches. Lower amounts up to 1 inch in the Rock Springs area. Winds gusting as high as 60 mph. * WHERE...East Sweetwater County. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel will be very difficult, especially along Interstate 80 due to the crosswind component. |
| Alert: | Winter Weather Advisory |
| Area(s): | South Lincoln County |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Weather Advisory issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Snow expected. Additional snow accumulations up to 1 inch. Winds gusting as high as 40 mph. * WHERE...South Lincoln County. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be difficult due to a combination of wind and falling snow. |
| Alert: | Winter Storm Warning |
| Area(s): | Casper Mountain |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Heavy snow possible. Additional snow accumulations between 3 and 6 inches possible. Winds could gust as high as 40 mph. * WHERE...Casper Mountain. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel will be very difficult. Areas of blowing snow could significantly reduce visibility. Heavy snow could break tree limbs as many trees have leafed out. |
| Alert: | Winter Storm Warning |
| Area(s): | Natrona County Lower Elevations |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Heavy snow expected. Total snow accumulations between 1 and 3 inches. Areas of higher amounts up to 4 inches between Hiland and Casper and for the south side of Casper. Winds gusting as high as 40 mph. * WHERE...Natrona County Lower Elevations. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel will be difficult, especially along US Highway 20/26 between Hiland and Casper. Heavy snow could break tree limbs as many trees have leafed out. |
| Alert: | Winter Storm Warning |
| Area(s): | Wind River Mountains East |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Heavy snow. Additional snow accumulations up to 2 inches, with 4 to 6 inches at the highest elevations. Winds gusting as high as 40 mph. * WHERE...Wind River Mountains East. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel will be very difficult, especially over South Pass. |
| Alert: | Winter Storm Warning |
| Area(s): | Green Mountains and Rattlesnake Range |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Storm Warning issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Heavy snow. Additional snow accumulations 1 to 4 inches. Winds gusting as high as 50 mph. * WHERE...Green Mountains and Rattlesnake Range. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel will be difficult due to a combination of wind and falling snow. |
| Alert: | Winter Weather Advisory |
| Area(s): | Wind River Mountains West |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Weather Advisory issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Snow expected. Additional snow accumulations between 3 and 5 inches. Winds gusting as high as 60 mph. * WHERE...Wind River Mountains West. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be difficult, especially along South Pass. The hazardous conditions could impact the Monday evening commute. |
| Alert: | Winter Weather Advisory |
| Area(s): | Rock Springs and Green River; Flaming Gorge |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Weather Advisory issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Snow expected. Additional snow accumulations up to 1 inch. Winds gusting as high as 55 mph. * WHERE...Flaming Gorge and Rock Springs and Green River. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be difficult, especially along Interstate 80. The hazardous conditions could impact the Monday evening commute. |
| Alert: | Winter Weather Advisory |
| Area(s): | Upper Green River Basin |
| Effective: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Onset: | 2026-05-18 @ 1:46 pm -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Riverton WY on 2026-05-18 @ 1:46 pm |
| Headline: | Winter Weather Advisory issued May 18 at 12:46PM MDT until May 18 at 6:00PM MDT by NWS Riverton WY |
| Description: |
* WHAT...Snow expected. Total snow accumulations up to 2 inches. Winds gusting as high as 45 mph. * WHERE...Upper Green River Basin. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be difficult due to a combination of wind and falling snow. |
| Alert: | Freeze Warning |
| Area(s): | Harding; Northern Perkins; Butte; Northern Meade Co Plains; Ziebach; Northern Foothills; Rapid City; Southern Foothills; Custer Co Plains; Pennington Co Plains; Haakon; Western Fall River; Northern Oglala Lakota; Northern Jackson; Bennett; Sturgis/Piedmont Foothills; Southern Meade Co Plains; Hermosa Foothills; Eastern Fall River; Southern Oglala Lakota; Southern Jackson; Southern Perkins; Northern Campbell; Southern Campbell; Western Crook; Weston County Plains; Newcastle; Northeastern Crook |
| Effective: | 2026-05-18 @ 12:49 pm -> 2026-05-19 @ 4:00 am |
| Onset: | 2026-05-19 @ 1:00 am -> 2026-05-19 @ 10:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Rapid City SD on 2026-05-18 @ 12:49 pm |
| Headline: | Freeze Warning issued May 18 at 11:49AM MDT until May 19 at 9:00AM MDT by NWS Rapid City SD |
| Description: |
* WHAT...Sub-freezing temperatures as low as 28 expected. * WHERE...Portions of northwestern and southwestern South Dakota and northeast Wyoming. * WHEN...From midnight tonight to 9 AM MDT Tuesday. * IMPACTS...Frost and freeze conditions could kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. |
| Alert: | Winter Storm Warning |
| Area(s): | Sierra Madre Range |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Storm Warning issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Heavy snow expected. Total snow accumulation 8 to 16 inches, mainly on the eastern side of the Range. Winds gusting as high as 50 mph with periods of blowing and drifting snow. * WHERE...Sierra Madre Range. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be very difficult to impossible. The hazardous conditions could impact the Monday morning and evening commutes. Strong winds could cause tree damage. * ADDITIONAL DETAILS...North to northeast facing slopes and ridges will see the highest accumulations, with accumulations much lower on the western side of the range near Dixon and Baggs. |
| Alert: | Winter Weather Advisory |
| Area(s): | Converse County Lower Elevations; Shirley Basin; Central Laramie Range and Southwest Platte County; South Laramie Range Foothills |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Weather Advisory issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Snow expected. Total snow accumulations 2 to 6 inches. Winds gusting as high as 35 mph. * WHERE...Converse County Lower Elevations, Shirley Basin, Central Laramie Range and Southwest Platte County, and South Laramie Range Foothills. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be very difficult. The hazardous conditions could impact the Monday morning and evening commutes. |
| Alert: | Winter Storm Warning |
| Area(s): | South Laramie Range |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Storm Warning issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Heavy snow. Total snow accumulations 7 to 14 inches expected with locally higher amounts. Winds could gust as high as 30 to 40 mph with some drifting snow expected. * WHERE...South Laramie Range including the Interstate 80 Summit between Cheyenne and Laramie. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Roads, and especially bridges and overpasses, will likely become slick and hazardous. |
| Alert: | Winter Storm Warning |
| Area(s): | North Laramie Range; Snowy Range |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Storm Warning issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Heavy snow. Total snow accumulations 10 to 20 inches expected with locally higher amounts possible. Winds could gust as high as 30 to 40 mph with periods of blowing and drifting snow, especially above 8500 feet. * WHERE...Snowy Range and North Laramie Range. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Heavy wet snow. Roads, and especially bridges, will likely become slick and hazardous. |
| Alert: | Winter Storm Warning |
| Area(s): | Ferris/Seminoe/Shirley Mountains |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Storm Warning issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Heavy snow and periods of drifting snow. Total snow accumulations 6 to 12 inches with higher amounts near the mountains. Winds could gust as high as 35 to 45 mph with periods of blowing and drifting snow. * WHERE...North Snowy Range Foothills including Arlington and Elk Mountain along Interstate 80, and Ferris/Seminoe/Shirley Mountains. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Roads, and especially bridges and overpasses, will likely become slick and hazardous. Scattered power outages possible due to heavy wet snow on trees and powerlines. |
| Alert: | Winter Weather Advisory |
| Area(s): | Laramie Valley |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Weather Advisory issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Snow and blowing snow expected. Total snow accumulations between 2 to 6 inches. Winds gusting as high as 35 mph. * WHERE...Laramie Valley. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be very difficult. The hazardous conditions could impact the Monday morning and evening commutes. * ADDITIONAL DETAILS...Portions of the Laramie Valley including Laramie itself could see amounts on the lower end due to westerly winds, but portions of the Valley including I-80 may see on the higher end of these amounts. |
| Alert: | Winter Storm Warning |
| Area(s): | Central Carbon County |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Severe |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Storm Warning issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Heavy snow and periods of blowing snow. Total snow accumulations 5 to 10 inches expected with locally higher amounts near the mountains. Winds could gust as high as 45 mph. * WHERE...Central Carbon County. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Visibilities may drop below 1/4 mile due to falling and blowing snow. |
| Alert: | Blizzard Warning |
| Area(s): | North Snowy Range Foothills |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Severity: | Extreme |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Blizzard Warning issued May 18 at 8:40AM MDT until May 18 at 3:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Blizzard conditions currently occurring along I-80 in the North Snowy Range Foothills. Additional snow accumulations between 2 and 6 inches. Winds gusting as high as 50 mph. * WHERE...North Snowy Range Foothills including Arlington and Elk Mountain along Interstate 80. * WHEN...Until 3 PM MDT this afternoon. * IMPACTS...Visibilities may drop below 1/4 mile due to falling and blowing snow. Plan on slippery road conditions. The hazardous conditions could impact the Monday evening commute. Gusty winds could bring down tree branches. |
| Alert: | Winter Weather Advisory |
| Area(s): | Southwest Carbon County |
| Effective: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 4:00 pm |
| Onset: | 2026-05-18 @ 9:40 am -> 2026-05-18 @ 7:00 pm |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Cheyenne WY on 2026-05-18 @ 9:40 am |
| Headline: | Winter Weather Advisory issued May 18 at 8:40AM MDT until May 18 at 6:00PM MDT by NWS Cheyenne WY |
| Description: |
* WHAT...Snow and periods of blowing snow. Total snow accumulations 3 to 6 inches, locally heavier in the northern extent of the zone. Winds gusting as high as 50 mph. * WHERE...Southwest Carbon County. * WHEN...Until 6 PM MDT this evening. * IMPACTS...Travel could be very difficult. The hazardous conditions could impact the Monday morning and evening commutes. Strong winds could cause tree damage. |
| Alert: | Winter Weather Advisory |
| Area(s): | Western Uinta Mountains; Southwest Wyoming |
| Effective: | 2026-05-17 @ 11:08 pm -> 2026-05-18 @ 2:15 pm |
| Onset: | 2026-05-17 @ 11:08 pm -> 2026-05-19 @ 1:00 am |
| Severity: | Moderate |
| Certainty: | Likely |
| Urgency: | Expected |
| Issued By: | NWS Salt Lake City UT on 2026-05-17 @ 11:08 pm |
| Headline: | Winter Weather Advisory issued May 17 at 10:08PM MDT until May 19 at 12:00AM MDT by NWS Salt Lake City UT |
| Description: |
* WHAT...Snow expected. Total snow accumulations of 6 to 14 inches for the Western Uinta Mountains with locally higher amounts further east into the Uinta mountains, and 2 to 6 inches for southwest Wyoming with locally in excess of 10 inches closer to the north slopes of the Uintas. * WHERE...In Utah, Western Uinta Mountains. In Wyoming, Southwest Wyoming. * WHEN...Until midnight MDT Monday Night. * IMPACTS...Travel could be difficult at times. Traction law restrictions may be enacted. |