Powerful El Niño Could Bring Unexpected Winter Weather To PA

Winter in Pennsylvania could hold unexpected shifts this year as a powerful El Niño alters storm paths nationwide.

The National Oceanic and Atmospheric Administration said this week in a new 2026-27 U.S. Winter Outlook that above average temperatures are anticipated throughout much of the northern U.S., while heightened precipitation is projected from California through Florida and along the Eastern Seaboard.

Spanning December through February, the seasonal forecast highlights the impact of an exceptionally strong El Niño. This phenomenon, driven by warm Pacific Ocean waters, reshapes air currents and storm routes over North America, often boosting southern storm activity while lowering precipitation in northern territories.

“As we know from decades of observations, a very strong El Nino will likely bring a southward and eastward shift to the jet stream for the contiguous U.S., which tilts the odds toward stormier weather across the South,” Ken Graham, director of NOAA’s National Weather Service, said in the forecast.

More precipitation could help replenish drought stricken areas, but Graham cautioned that heavy rain falling on dry ground can also cause flash flooding and mudslides.

What NOAA Predicts For PA

Warmer than average temperatures are expected across the northeast and mid-Atlantic, though winter storms remain likely. Above normal precipitation along the East Coast increases storm chances, potentially falling as rain, snow, or a wintry mix. While this could ease drought, mild temperatures may reduce snowfall totals.

What’s Ahead Elsewhere?

Here’s what NOAA predicts for the rest of the country.

Midwest and Great Lakes: The midwest and Great Lakes favor warmer than average temperatures, with parts of the Great Lakes potentially seeing less precipitation. This may limit sustained snow cover, though lake effect snow, Arctic cold, and major winter storms remain possible.

Northern Plains and Northern Rockies: The northern Rockies and northern plains lean warmer than average this winter, with mixed precipitation trends. Parts of the northern Rockies face drier conditions, with drought expected to develop or intensify there, as well as in eastern Washington and northeastern Oregon. For the northern Plains, the outlook shows equal chances of above or below normal precipitation, leaving snow totals uncertain.

Pacific Northwest and Northern California: The Pacific Northwest and northern California favor a warmer than average winter. Drier conditions are expected in parts of the northern mountain west, with drought potentially expanding or intensifying in eastern Washington and northeastern Oregon. Precipitation outlooks elsewhere remain uncertain, and the report omits specific mountain snowfall projections.

Southern California and the Southwest: Much of the southwest and southern California favors a wetter than average winter, potentially easing drought. Temperatures have equal chances of being above, near, or below average. An active southern storm track raises heavy rain and flood risks, while mountain snowfall depends on storm timing and temperatures.

Southern Plains and Texas: El Niño favors a stormier winter across the southern Plains, increasing precipitation that could ease extended drought, though rainfall timing, amounts, and individual winter storms remain uncertain.

Gulf Coast and Southeast: El Niño will likely bring above average winter precipitation and potential flooding to the Gulf Coast and southeast. While Florida and parts of the Southeast expect near normal temperatures, areas farther north and east lean warmer. Additional rain may ease local drought.

Ohio and Tennessee Valleys: The Ohio and Tennessee valleys favor warmer than average winter temperatures, with equal chances of above, near, or below average precipitation. Snow, ice, and rain will depend on individual storm tracks and cold air availability.

Alaska and Hawaii: Warmer than average temperatures are favored across much of Alaska, while many areas have increased chances of below average precipitation. The outlook also favors drier than average conditions in Hawaii, although temperatures there remain uncertain.

What It Means For Snow

Despite the stronger El Niño and its expected influence on storm tracks, NOAA is not predicting specific winter snowfall totals.

Seasonal outlooks estimate whether temperatures and overall precipitation will be above, below or near historical averages. They do not reliably predict how much snow will fall in a particular community months in advance.

A warmer than average winter does not rule out major snowstorms, and a wetter than average winter does not necessarily mean more snow.

New Winter Storm Tracking Tools

NOAA has introduced several changes intended to help residents and emergency managers prepare for dangerous winter weather.

Its new Probabilistic Precipitation Portal provides ranges of possible snow, ice and rainfall amounts, including the likelihood of precipitation exceeding certain thresholds.

The National Weather Service will also begin using the designation “particularly dangerous situation” in select blizzard and ice storm warnings when forecasters have high confidence that exceptionally dangerous conditions are developing.

The designation is reserved for rare storms that pose extraordinary threats to lives, property and emergency services.

NOAA will update its seasonal winter outlook on Nov. 19.