Rain and snow hit Northern California as an unseasonably cold spring storm pushed south through parts of Northern California on Thursday, bringing a welcome break in the drought.

As Breitbart News reported on April 9, the National Oceanic and Atmospheric Administration (NOAA) officially declared a strong El Niño advisory reflecting substantially above-average surface sea temperatures forming across the equatorial Pacific with a 70 percent probability that America could experience a monster winter like the El Niño that hit in 1997-1998, causing torrential rains in the Southeast, ice storms in the Northeast, tornadoes in Florida, and mass flooding in California.

Showers fell across the state while snow fell high in the Sierra Nevada Mountains most peaks that hold snow until the summer are already bone-dry. Yosemite National Park received snow at high elevations, and the popular Tioga and Glacier Point roads were temporarily closed due to icy conditions, the Park Service said.

The Sierra Crest above 7,000 feet received between 4 to 8 inches of snow, according to Sacramento’s KCRA.com reporters. Some viewers sent photos of light snow flurries as low as 4,000 feet. Chains or snow tires were required for Highway 50 from Twin Bridges to Meyers.

The Northern Sierras on Friday are expected to reach highs in the low to mid-40s, while the foothills may reach high temperatures of the mid-60s with showers and isolated thunderstorms predicted.

El Niño does not come to North America; it is a phenomenon of periodic warming in the equatorial waters of the Pacific Ocean. Normally, the trade winds along the equator push the warmest waters into the western portions of the Pacific. But on an irregular basis of typically two to seven years, the trade winds slacken, or sometimes even reverse direction, and warmer-than-normal water accumulates along the equator in the central and eastern Pacific. Although El Niño occurs in the tropics, it impacts the globe, as the location of a huge mass of warming water causes the jet stream to shift.

Since 1950, there have been 22 years in which the equatorial Pacific has warmed enough to be classified as an El Niño sometime during the year. But only the six years of 1957, 1965, 1972, 1982, 1987, and 1997 have become “strong” El Niños. The larger the area and the greater the amount of warming of the eastern Pacific’s equatorial waters, the greater the weather impact on other regions.

NOAA’s Climate Prediction Center announced on March 5 that sea-surface temperatures in the eastern tropical Pacific were beginning to be “elevated,” and local rainfall patterns were shifting in response. But on April 9, NOAA issued an El Niño advisory that there was a 70 percent chance that “El Niño would continue through Northern Hemisphere summer 2015, and a greater than 60% chance it will last through autumn.” The Advisory was issued as a “consolidated effort” of the National Oceanic and Atmospheric Administration, the National Weather Service, and other government funded weather research institutions.

NOAA emphasized that their El Niño forecast is “supported by the increase in subsurface temperatures, enhanced convection over the Date Line, and the increased persistence of low-level westerly wind anomalies.”

Of the ten costliest flood years in California since 1950, four happened during a season when there was a strong El Niño. The major weather pattern that causes flooding in California is when a strong surge of subtropical moisture dumps copious amounts of rain over a portion of California for five to seven days.