Ontario, CA Warnings, Watches and Advisories

Do not drive vehicles through flooded areas. The water depth or fast flowing water/mud/debris from a flash flood will make road conditions unsafe. Do not rely soley on data presented here or other third-party websites - always check your official national and local weather service agency website, socials, radio and/or TV stations for making critical decisions related to weather events.

Please carefully read each posted Warning and Alert as it relates to the area(s) being affected. We may provide a wider range of issued severe weather warnings for surrounding cities and counties, so some alerts may not directly impact this location. This is done to help with preparing for severe weather that may overlap or be heading towards Ontario.

Use the Radar Maps link provided to understand the trajectory of a storm.

Coastal Flood Advisory issued November 17 at 8:26AM PST until November 17 at 2:00PM PST by NWS Eureka CA

* WHAT...High astronomical tides will cause minor flooding in low lying areas around Humboldt Bay. Up to one quarter foot of saltwater inundation above ground level is possible near shorelines and tidal waterways. Between 8.7 and 8.9 feet MLLW at the North Spit tide gauge is predicted. * WHERE...Northern Humboldt Coast County. * WHEN...Until 2 PM PST this afternoon. High tide is at 11:45 AM at the Humboldt Bay North Spit tide gauge. Saltwater inundation will be possible 1 to 2 hours before and after high tide. * IMPACTS...Flooding of low lying areas around Humboldt Bay including parks and roads with only isolated closures expected. Flooding will likely impact Jackson Ranch Road in the Arcata Bottoms and several roads in King Salmon.

Hydrologic Outlook issued November 17 at 6:18AM PST by NWS Eureka CA

ESFEKA * WHAT...There is moderate to high model agreement that a strong and prolonged atmospheric river will impact NW California mid to late week. For the northern half of the area. Rain will be heaviest on Wednesday with 2 to 4 inches of rain most likely across the northern half of the area. High peaks in the King Range could see 6 to 8 inches of rain over 24 hours. Most models show more moderate but persistent rain continuing Thursday through next Saturday with most likely rainfall of 1 to 3 inches each day. Total Storm amounts could easily reach between 8 and 14 inches over 4 days. * WHERE...The greatest risk is for Humboldt and Del Norte Counties where soils are already near saturation. Rain will be lighter though still significant for Mendocino and Lake Counties, though generally drier soils will reduce the flood risk. Much of the precipitation in Trinity County will likely fall as snow with snow levels in the eastern half of the county as low as 2500 feet. * WHEN...Greatest risk of heavy rain during the day on Wednesday. More moderate but prolonged rain Thursday through Saturday. The forecast is more uncertain further out. Long range models show the potential for rain to continue into Thanksgiving Week. * IMPACTS...Such rain amounts will greatly increase the risk of flooding, especially for the northern half of the area where soils have already been saturated by previous rain events. Expect flooding on in low lying areas, areas with poor drainage, and increased risk of debris on roadways. Rivers will rapidly rise. Long range river forecasts indicate a 10 to 30% chance of rivers such as the Mad River, Eel River, and Smith River reaching monitor stage by Thursday. * Stay tuned to the weather forecast over the next couple days as forecast confidence and details will likely increase. Beyond rain, this storm is also expected to bring widespread damaging wind.

High Wind Watch issued November 17 at 5:08AM PST until November 20 at 1:00AM PST by NWS Eureka CA

* WHAT...Southeast winds 25 to 35 mph with gusts up to 60 mph possible along shore and in the Eel River Delta. * WHERE...Northern Humboldt Coast. * WHEN...From Tuesday evening through late Tuesday night. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles. Wind gusts will be particularly strong along windward ridges, exposed coastal headlands, and along the Eel River Delta.

High Wind Watch issued November 17 at 5:08AM PST until November 20 at 4:00AM PST by NWS Eureka CA

* WHAT...Southeast winds 20 to 30 mph with gusts up to 60 mph possible. * WHERE...Humboldt Interior along exposed ridges. * WHEN...From Tuesday evening through late Tuesday night. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles.

High Wind Watch issued November 17 at 5:08AM PST until November 20 at 7:00AM PST by NWS Eureka CA

* WHAT...South winds 20 to 30 mph with gusts up to 65 mph possible along shore and along high ridges. * WHERE...Del Norte County. * WHEN...From Tuesday afternoon through Wednesday morning. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles. Wind gusts will be particularly strong along windward ridges and exposed coastal headlands.

High Wind Watch issued November 17 at 5:08AM PST until November 20 at 10:00AM PST by NWS Eureka CA

* WHAT...South winds 35 to 45 mph with gusts up to 85 mph possible along the highest ridges of the King Range. * WHERE...Southwestern Humboldt. * WHEN...From Tuesday afternoon through Wednesday morning. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles. Wind gusts will be particularly strong along windward ridges and exposed coastal headlands.

Lake Wind Advisory issued November 17 at 4:30AM PST until November 18 at 4:00AM PST by NWS Reno NV

* WHAT...Southwest winds 15 to 25 mph with gusts of 30 to 40 mph and waves 2 to 4 feet for Lake Tahoe. * WHERE...Greater Lake Tahoe Area. * WHEN...From 8 PM this evening to 4 AM PST Monday. * IMPACTS...Small boats, kayaks and paddle boards will be prone to capsizing and should remain off lake waters until conditions improve.

High Surf Advisory issued November 17 at 4:23AM PST until November 19 at 9:00AM PST by NWS Los Angeles/Oxnard CA

* WHAT...Large breaking waves of 8 to 12 feet across west and northwest facing beaches with dangerous rip currents. * WHERE...San Luis Obispo County Beaches and Santa Barbara County Central Coast Beaches. * WHEN...From 2 AM Monday to 9 AM PST Tuesday. * IMPACTS...There is an increased risk for ocean drowning. Rip currents can pull swimmers and surfers out to sea. Large breaking waves can cause injury, wash people off beaches and rocks, and capsize small boats near shore. * ADDITIONAL DETAILS...Minor coastal flooding is possible on west and northwest-facing beaches a couple hours on either side of the morning high tide on Monday. High tide on Monday will occur around 1030 AM PST.

Wind Advisory issued November 17 at 3:50AM PST until November 17 at 7:00PM PST by NWS Medford OR

* WHAT...For the Wind Advisory, southwest winds 20 to 35 mph with gusts up to 50 mph. For the High Wind Watch, south winds 30 to 50 mph with gusts up to 70 mph possible. * WHERE...Lake County and eastern Klamath County, and Modoc County. This includes Silver Lake, Summer Lake, Paisley, Adel, the Warner Mountains, and portions of Highways 31, 140, and 395. * WHEN...For the Wind Advisory, until 7 PM PST this evening. For the High Wind Watch, from Tuesday afternoon through Wednesday morning. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles. * ADDITIONAL DETAILS...After Wednesday morning, additional episodes of strong winds are possible during the remainder of the week.

High Wind Watch issued November 17 at 3:50AM PST until November 20 at 7:00AM PST by NWS Medford OR

* WHAT...For the Wind Advisory, southwest winds 20 to 35 mph with gusts up to 50 mph. For the High Wind Watch, south winds 30 to 50 mph with gusts up to 70 mph possible. * WHERE...Lake County and eastern Klamath County, and Modoc County. This includes Silver Lake, Summer Lake, Paisley, Adel, the Warner Mountains, and portions of Highways 31, 140, and 395. * WHEN...For the Wind Advisory, until 7 PM PST this evening. For the High Wind Watch, from Tuesday afternoon through Wednesday morning. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles. * ADDITIONAL DETAILS...After Wednesday morning, additional episodes of strong winds are possible during the remainder of the week.

High Wind Watch issued November 17 at 3:50AM PST until November 20 at 7:00AM PST by NWS Medford OR

* WHAT...South winds 30 to 45 mph with gusts up to 65 mph possible in the Shasta Valley. * WHERE...Central Siskiyou County. This includes Interstate 5, with the strongest winds likely near Weed. * WHEN...From Tuesday afternoon through Wednesday morning. * IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel could be difficult, especially for high profile vehicles.

Winter Storm Warning issued November 17 at 2:59AM PST until November 18 at 10:00PM PST by NWS Medford OR

* WHAT...Heavy snow expected Above 3000 Feet. Total snow accumulations between 4 and 12 inches. Winds gusting as high as 45 mph. * WHERE...Western Siskiyou County County. This includes the higher terrain and mountain passes. * WHEN...From 4 PM this afternoon to 10 PM PST Monday. * IMPACTS...Travel could be very difficult to impossible. The hazardous conditions could impact the Monday morning and evening commutes. Gusty winds could bring down tree branches.

Winter Storm Warning issued November 17 at 2:59AM PST until November 18 at 10:00PM PST by NWS Medford OR

* WHAT...Heavy snow expected for the higher terrain. Total snow accumulations between 6 and 12 inches. Southwest to west winds gusting as high as 55 mph. * WHERE...Modoc County and North Central and Southeast Siskiyou County Counties. This includes Highway 97 near Mt.Hebron, Medicine Lake, and the Warner Mountains. * WHEN...From 4 PM this afternoon to 10 PM PST Monday. * IMPACTS...Travel could be very difficult to impossible. The hazardous conditions could impact the Monday morning and evening commutes. Strong winds could cause extensive damage to trees and power lines.

Coastal Flood Advisory issued November 17 at 12:02AM PST until November 18 at 4:00PM PST by NWS San Francisco CA

* WHAT...Minor coastal flooding expected. * WHERE...Bayshore along the San Francisco Bay and San Pablo Bay. * WHEN...Until 4 PM PST Monday. * IMPACTS...Flooding of lots, parks, and roads with only isolated road closures expected. * ADDITIONAL DETAILS...Tidal levels are increasing as a result of higher astronomical tides. Low lying areas within the San Francisco Bay Area may see minor flooding as a result during high tide. San Francisco highest tides are Sunday 6.89 ft at 11:26 am and Monday 6.60 ft at 12:11 pm.