El Niño update, October 27: what to know

What’s happening

• Active NWS alert: Freeze Warning, in effect until 9:00 AM PDT (NWS Eureka CA), for parts of Northwestern Interior Mendocino, Northeastern Interior Mendocino and Northern Lake. Source: NWS active alerts — CA (opens in a new tab)
• Active NWS alert: Coastal Flood Advisory, in effect until 3:00 PM PDT (NWS Eureka CA), for parts of Northern Coastal Humboldt. Source: NWS active alerts — CA (opens in a new tab)
• Active NWS alert: Coastal Flood Advisory, in effect until 5:00 PM PDT (NWS San Francisco CA), for parts of Coastal North Bay Including Point Reyes National Seashore and San Francisco Peninsula Coast. Source: NWS active alerts — CA (opens in a new tab)

What to watch for

• NOAA’s Climate Prediction Center says: “Moderate risk of heavy precipitation for portions of southwestern Oregon and northwestern California, Fri-Sun, Nov 6-8.” Source: CPC U.S. Hazards Outlook (opens in a new tab)
• NOAA’s Climate Prediction Center says: “Moderate risk of heavy snow for portions of the northern Sierra Nevada and Klamath Ranges, Fri-Sun, Nov 6-8.” Source: CPC U.S. Hazards Outlook (opens in a new tab)
• The Weather Prediction Center says: “Then over the weekend, Pacific moisture will increase across the West and bring broadening precipitation chances to California and across the Intermountain West.” Source: WPC Extended Forecast Discussion (opens in a new tab)

Active NWS alerts: Coastal Flood Advisory: 3 (CA) · Freeze Warning: 1 (CA) · Frost Advisory: 1 (CA)

What’s happening

• Active NWS alert: Coastal Flood Warning, in effect until 1:00 PM PDT (NWS San Diego CA), for parts of San Diego County Coastal Areas and Orange County Coastal. Source: NWS active alerts — CA (opens in a new tab)
• Active NWS alert: Coastal Flood Advisory, in effect until 1:00 PM PDT (NWS Los Angeles/Oxnard CA), for parts of Catalina and Santa Barbara Islands. Source: NWS active alerts — CA (opens in a new tab)
• NWS Los Angeles/Oxnard says: “Gradual cooling will continue through the week, with increasing cloud coverage and a high chance of rain sometime from Friday- Monday, with highest chances Saturday (Halloween) through Sunday.” Source: Area Forecast Discussion — Los Angeles/Oxnard (opens in a new tab)

What to watch for

No items for this region in this post.

Active NWS alerts: Coastal Flood Advisory: 2 (CA) · Coastal Flood Warning: 1 (CA)

What’s happening

• Active NWS alert: Flood Warning (NWS Albuquerque NM), for parts of Rio Arriba, NM. Source: NWS active alerts — NM (opens in a new tab)
• The Storm Prediction Center says: “Isolated severe thunderstorms are possible later today over a small part of southeast New Mexico and far west Texas.” Source: SPC Day 1 Convective Outlook (opens in a new tab)
• The U.S. Drought Monitor: “AZ drought coverage, week of 2026-10-20: 24.21% none, D0 75.79%, D1 41.09%, D2 11.70%, D3 0.00%, D4 0.00%.” Source: U.S. Drought Monitor — AZ (opens in a new tab)

What to watch for

• NOAA’s Climate Prediction Center says: “Moderate risk of heavy snow for portions of the northern Sierra Nevada and Klamath Ranges, Fri-Sun, Nov 6-8.” Source: CPC U.S. Hazards Outlook (opens in a new tab)
• NOAA’s Climate Prediction Center says: “Slight risk of heavy snow for the Cascades, Klamath and Sierra Nevada ranges, Fri-Tue, Nov 6-10.” Source: CPC U.S. Hazards Outlook (opens in a new tab)
• NOAA’s Climate Prediction Center says: “Farther to the south, weak riding is forecast across portions of the southwestern CONUS with downstream troughing predicted over the Southern Plains and Lower Mississippi Valley.” Source: CPC 6-10 / 8-14 Day Outlook Discussion (opens in a new tab)

Active NWS alerts: Flood Warning: 2 (NM)

What’s happening

• Active NWS alert: Flood Warning, in effect until 5:00 PM CDT (NWS Midland/Odessa TX), for parts of Presidio, TX. Source: NWS active alerts — TX (opens in a new tab)
• Active NWS alert: Rip Current Statement, in effect until 7:00 PM CDT (NWS Brownsville TX), for parts of Kenedy Island, Willacy Island and Cameron Island. Source: NWS active alerts — TX (opens in a new tab)
• Active NWS alert: Coastal Flood Advisory, in effect until 4:00 AM CDT (NWS Corpus Christi TX), for parts of Aransas Islands, Kleberg Islands and Nueces Islands. Source: NWS active alerts — TX (opens in a new tab)

What to watch for

• NOAA’s Climate Prediction Center says: “Slight risk of heavy precipitation for most of the East Coast states, Tennessee Valley, and the eastern Gulf Coast region, Wed-Thu, Nov 4-5.” Source: CPC U.S. Hazards Outlook (opens in a new tab)
• The Weather Prediction Center says: “With the new 12z guidance today, models continue to struggle with the placement of this new low with some guidance (such as the 12z CMC) as far north as Nebraska, and others (such as the 12z ECMWF) as far south as the Texas and Oklahoma…” Source: WPC Extended Forecast Discussion (opens in a new tab)
• NOAA’s Climate Prediction Center says: “Above normal precipitation is modestly favored for southern Texas, where some models are showing the potential for low level return flow moisture during the middle or latter parts of the period.” Source: CPC 6-10 / 8-14 Day Outlook Discussion (opens in a new tab)

Active NWS alerts: Coastal Flood Advisory: 2 (TX) · Flood Warning: 1 (TX) · Rip Current Statement: 1 (TX)

What’s happening

• Active NWS alert: Coastal Flood Warning, in effect until 5:00 AM EDT (NWS Key West FL), for parts of Monroe Upper Keys, Monroe Middle Keys and Monroe Lower Keys. Source: NWS active alerts — FL (opens in a new tab)
• Active NWS alert: Coastal Flood Warning, in effect until 2:00 AM EDT (NWS Jacksonville FL), for parts of Inland Flagler, Eastern Clay and Eastern Putnam. Source: NWS active alerts — FL (opens in a new tab)
• Active NWS alert: Coastal Flood Warning, in effect until 2:00 AM EDT (NWS Melbourne FL), for parts of Coastal Volusia, Coastal Indian River and Coastal St. Lucie. Source: NWS active alerts — FL (opens in a new tab)

What to watch for

• The Weather Prediction Center says: “This rainy and stormy pattern will move east across the southeastern U.S. into the weekend, and locally heavy rain is possible.” Source: WPC Extended Forecast Discussion (opens in a new tab)

Active NWS alerts: Coastal Flood Advisory: 7 (GA, NC) · Rip Current Statement: 7 (FL, GA, SC, NC) · Coastal Flood Warning: 6 (FL) · Beach Hazards Statement: 4 (NC) · High Surf Advisory: 3 (FL) · Wind Advisory: 3 (FL) · Flood Warning: 2 (FL)