Fox News Weather Center

Sustained cool weather may wait until end of October to reach northeastern, midwestern US

With warm air set to dominate this week across the midwestern and northeastern United States, it may take until the end of October for cool weather to finally get the upper hand.

Cooler air is making a comeback following this weekend's surge of warmth and locally gusty showers, but it will not hang around long.

Temperatures will be back to more typical mid-October levels on Monday from the Midwest to the Northeast as a cold front sweeps off the coast.

NE Oct 15

Highs ranging from the 50s in northern New England and the upper Great Lakes to the 60s elsewhere are more common this time of year.

For those residents grabbing jackets before heading to school or work on Monday morning, an even chillier morning in the Northeast awaits on Tuesday. Temperatures by daybreak Tuesday will plummet into the 30s west of I-95 cities with frost in some interior locales.

Freezing temperatures will threaten any plants outdoors or crops that survived the cool shot at the start of October across the central Appalachians.

“After the brief cooldown to start the week, the eastern half of the country will see a warming trend through the end of the week,” AccuWeather Long-Range Meteorologist Max Vido said.

Frost Oct 15

Starting at midweek, highs in the 60s and 70s will dominate. Most communities will not see any rain as each day features a partly to mostly sunny sky. Calm mornings will gradually allow fog to return to the river valleys.

The weather this week will be perfect for hikes to see fall foliage, pumpkin picking, sporting events and fall festivals. Some residents may even want to fire up grills for dinner.

For cool weather fans, Vido anticipates true autumn weather finally winning the battle against the recent warm spells later this month.

“There are signs that suggest a flip in the weather pattern during the last week of October in what could lead to the first chance of sustained cool weather across the Midwest and Northeast,” he said.

Late week Oct 15

While the jet stream (a fast-flowing river of air along which storms ride) and cool air will get bottled back up in Canada this week, Vido expects it to drop southward later in October and not rapidly retreat.

The result will be an extended period of near- to below-normal temperatures in the Midwest and Northeast.

By the end of October, average highs range from the 40s and lower 50s in northern New England and the upper Great Lakes to the lower 60s across the Ohio Valley and the I-95 corridor of the mid-Atlantic.

Typical lows range from near 30 F to the lower 40s from north to south across these two regions.

“Below-normal temperatures will likely bring killing frosts and freezes to more of the interior Northeast and Great Lakes, away from the immediate lakeshores,” Vido said.

cool down Oct 15

“It also may be time to finally stoke fireplaces or turn on the furnace for many residents.”

Those planning their Halloween costumes should not let the warm spell this week lead to them shivering on the holiday. Be sure to plan to have an extra layer of clothing underneath your costume or incorporate in a jacket.

Vido expects one more way for the cool spell later this month to give residents more evidence that winter is on its way.

“It is even possible that areas across the Upper Midwest see their first snowflakes, which historically happens by late October,” Vido said.