Manchester, NH – Southern New Hampshire is preparing for a chilly late-October weekend, as patchy fog and the season’s first frost make an appearance across parts of the region. The National Weather Service (NWS) in Gray–Portland warns of cooler mornings, particularly in low-lying areas where temperatures could dip into the mid-30s by Sunday.
The Forecast: Foggy Mornings and Crisp Autumn Days
Early Friday began with dense fog across the Merrimack Valley, softening headlights and slowing morning commuters. According to the NWS, skies will gradually clear later in the day, giving way to partial sunshine.
High temperatures are expected to reach around 58°F, with only a slight chance of light showers in the afternoon. Rainfall totals are forecast to stay below a tenth of an inch, and winds will shift lightly westward by evening, maintaining a calm and mild fall atmosphere.
Meteorologists say the combination of moist air and cooling overnight temperatures will lead to fog redevelopment in several areas both Saturday and Sunday mornings.
Weekend Outlook: Clearer Skies, Colder Nights
Saturday will bring a cooler but brighter day, with highs near 55°F and lows dropping into the mid-30s overnight. The return of patchy fog is likely in the early hours, especially in valleys near the Merrimack and Piscataquog Rivers.
Residents are urged to allow extra travel time on foggy mornings and to protect outdoor plants, as the chill could cause localized frost formation.
By Sunday, the pattern shifts to mostly sunny skies with crisp, dry air—a picture-perfect setup for yard cleanup or early Halloween decorating. Daytime highs will hover in the low 50s, but temperatures are expected to drop quickly after sunset, reinforcing the first frosty signs of late fall.
Statements and Public Guidance
The National Weather Service has advised residents to stay aware of rapidly changing visibility conditions during early morning hours.
“Drivers should slow down, use low beams, and allow for extra stopping distance when traveling through fog-prone areas,” an NWS spokesperson said.
Local garden centers and horticultural experts also recommend covering sensitive plants or bringing potted greenery indoors during the coldest nights of the weekend to prevent frost damage.
Background: A Classic Late-October Pattern
This weekend’s conditions align with a typical New England transition pattern, where high-pressure systems settle in behind weak cold fronts, creating clear nights and chilly mornings.
Meteorologists note that southern New Hampshire’s first frost usually arrives between October 20 and October 28, putting this year’s onset right on schedule. The clear skies and calm winds expected Saturday night create ideal conditions for radiational cooling, which allows heat to escape and temperatures to plummet near freezing.
Looking Ahead: Clouds and Showers Early Next Week
Looking into early next week, cloud cover is expected to increase by Tuesday and Wednesday, bringing a chance of light showers. Temperatures, however, will remain seasonable, staying in the mid-50s by day and the upper 30s at night.
The broader forecast suggests a classic autumn finish to October, with dry air, falling leaves, and that familiar pre-winter chill setting the tone for the start of November.
Conclusion
With fog, frost, and falling temperatures arriving hand in hand, this weekend marks New Hampshire’s transition from crisp autumn afternoons to frosty fall mornings. Residents should prepare for cooler nights, drive carefully during foggy commutes, and enjoy the clear, colorful days that define late October in New England.
How are you preparing for the weekend chill and first frost? Share your tips and experiences in the comments below.
