NOAA’s National Weather Service notes that El Nino has developed in the tropical Pacific and has issued an El Nino advisory.
El Nino, the warm phase of the El Nino Southern Oscillation, is predicted to intensify to a moderate or strong level this fall. Forecasters predict a 63% chance of sea surface temperatures exceeding 2.0 degrees Celsius in the Nino-monitored region of the Pacific. If this threshold is surpassed, NOAA considers the event a “very strong” El Nino.
What is El Nino?
NOAA declares an El Nino (Spanish for “little boy”) has formed when temperatures in the equatorial Pacific are 0.5 degree Celsius above average for several consecutive months. Additionally, NOAA monitors the atmosphere above this region of the Pacific, looking for a pattern called the Walker Circulation, a massive east-to-west air flow driven by the temperature and pressure differences between the warm western and cool eastern oceans. When the Walker Circulation breaks down and warmer water shifts east toward South America, El Nino is declared.
What does El Nino mean for U.S. weather?El Nino tends to be strongest during the winter months, and its global impacts are typically most significant in the northern hemisphere winter. During a typical El Nino winter, the jet stream over the north Pacific Ocean tends to shift southward, bringing the storm track over the southern tier of the U.S. The southward shift in the storm track also leads to drier conditions over the Northern Rockies and Ohio and Tennessee valleys. For temperatures, El Nino often leads to a warmer than usual winter over the northern United States.
Usual impacts of El Nino can include:
Stronger upper-level winds tend to suppress storm and hurricane development in the Atlantic Basin, while weaker winds tend to enhance tropical development in the eastern and central Pacific basins.
Stormier weather is more likely in the Southern U.S., with chances of both rain and snow increased during El Nino winters
High tide flooding could become a higher risk in parts of the U.S., especially on the West Coast.
Changes in the migration of fish and other oceanic organisms, with warm water species moving north while cold water species move farther north or into deeper waters. These behavioral changes impact growth, survival and reproduction.
The Climate Prediction Center is forecasting above normal temperatures for July, and rainfall could average above, below or about average. The 90-day extended outlook for the months of July, August and September is continuing with above normal temperatures and once again precipitation could average above, below or about average.
Over 98% of lightning casualties are from people outdoors in a storm. Get inside as soon as you hear thunder in the distance, and your chances of staying safe grow dramatically. Did you know that lightning fatalities most frequently come from places that are actually outside the areas where it’s raining? Lightning can strike over 10 miles from a storm’s rain area. If you can hear the thunder, you’re close enough to be struck. Don’t take chances!
Past El Nino episodes have also enhanced the formation of harmful algal blooms along the U.S. West Coast.
Hurricane season was only two weeks old when Arthur formed in the northwestern Gulf of America. Arthur produced lots of rain before eventually dissipating.
The next few storms will be named Bertha, Cristobal, Dolly and Edouard. With a strong El Nino in place, hurricane season is forecast to be below average. Forecasters predict 8-14 named storms, 3-6 hurricanes and 1-3 major hurricanes.
Total precipitation for the first six months of 2026 totaled 15.94 inches, compared to an average of 20.09 inches. Despite periods of heavy rain in both late May and June, Cumberland is still running a deficit of 4.15 inches for the year.
Residents woke up to some very chilly temperatures at the beginning of June, with some areas dipping into the 30s. Temperatures rebounded nicely but seemed to be all over the place most of the month. Precipitation totaled 2.93 inches, compared to the average of 3.87 inches — .74 inch below normal.
The maximum temperature for the month was 93 degrees and the minimum temperature dipped to 40 degrees. The average maximum temperature was 82.8 degrees and the average minimum temperature was 58.8 degrees. Temperatures rose into the 90s on two days, 21 days remained in the 80s and seven days were in the 70s. Thunder was noted on four occasions, and fog was also observed on four days. There was no outstanding weather to report during the month of June.
July marks another important milestone for the Golden/Thomas family. We now have 79 years of observing Cumberland’s weather and working on year number 80! My granddad Robert Golden, my brother Keith and I have a lot to be proud of, and it certainly has been an exciting time.
Millions of folks are going anywhere to get cool this Fourth of July weekend. Scorching heat and stifling humidity greeted the new month with going outdoors becoming unbearable. Happy 250th birthday America, and a happy July Fourth to all Weatherwise readers. Relax and enjoy. See you next month.
Tim Thomas is a graduate of Fort Hill High School and has been affiliated with the National Weather Service since 1965.