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CheckWeather US›New Jersey›Mountainside

Mountainside weather

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NWSNational Blend (NBM)
52°
Mainly clear
Feels 48° · Wind 2 mph · Humidity 62%
AmericanNOAA GFS
49°
Overcast
Feels 44° · Wind 5 mph · Humidity 61%
EuropeanECMWF
48°
Overcast
Feels 43° · Wind 3 mph · Humidity 57%

Latest for Mountainside: NWS (National Blend (NBM)): 52° Mainly clear · American (NOAA GFS): 49° Overcast · European (ECMWF): 48° Overcast.

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Mountainside weather alerts and warnings

active National Weather Service watches, warnings and advisories

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Mountainside weather in numbers

from 30 years of measured normals

Mountainside swings 62°F across the year, from 85°F highs in July to 23°F lows in February, and July is usually the wettest month in a year that brings about 53 in of precipitation.

Warmest month
July
85°F average high
Coldest month
February
23°F average low
Wettest month
July
53 in a year
Below freezing
4 months
January, February, March and December
Comfortable
4 months
April, May, September and October
Residents
6,885
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The weather map: all three models at once

NWS, American, European side by side around Mountainside and nearby towns.Live rain radar →
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Mountainside hourly forecast: next 14 hours

consensus of the three models

Rain in the next 24 hours, model by model

each model's own hourly precipitation, side by side

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Mountainside 10-day forecast, out to 14 days

where the models agree, and where they split

Mountainside, New Jersey (NJ) is at its warmest in Jul (average highs near 85°F) and coldest in Feb (lows around 23°F), with roughly 53 in of precipitation across the year. Below, compare what NWS, American, European forecast for Mountainside right now, and see exactly where they disagree.

We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.

Mountainside climate by month

average daytime high and overnight low across a typical year (1991-2020)
Jan
38°
25°
Feb
41°
23°
Mar
49°
31°
Apr
60°
41°
May
71°
51°
Jun
81°
60°
Jul
85°
66°
Aug
82°
65°
Sep
75°
58°
Oct
65°
46°
Nov
53°
36°
Dec
43°
29°

Source: 1991-2020 averages, ERA5 for this place adjusted with NASA POWER.

How the weather around Mountainside has changed since 1995

Mountainside sits in the same roughly 50 km square of NASA's reanalysis as Staten Island. That square ran 1.6°F warmer in 2015-2024 than in 1995-2004. See the full 30-year picture on the Staten Island page.

Which forecast is most accurate in the US?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
93
/100rank #1
91±0.9°F97±1.1 mph9396% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
82
/100rank #2
83±1.7°F94±2.0 mph7184% hitNOAA / NCEP (United States)College Park, Maryland, USA

The CheckWeather Score blends temperature, wind and rain accuracy, each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.

What do you think of the forecasts?

your vote counts

The accuracy above is the measured record. This is your opinion: which forecast service do you trust most in United States? Give each 1 to 5 stars.

NWSNational Blend (NBM)
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AmericanNOAA GFS
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EuropeanECMWF
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One vote per service. Anonymous: we store no personal data, only a one-way hash of your connection for a day to stop double votes.

Common questions

What's the weather in Mountainside today?
On this page we show what NWS, American, European each forecast for Mountainside today, side by side and updated live. When all three agree the forecast is reliable; when they split, we flag it so you know the day is genuinely less certain.
Will it rain in Mountainside today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Mountainside and flag the days where the models disagree on whether showers actually arrive, which is exactly when a single app can catch you out.
Which forecast is most accurate for Mountainside?
No single model is always right. NWS, American, European each run their own physics, so we line all three up: when they agree the Mountainside forecast is reliable, and when they split you should expect surprises. See our tested US accuracy scoreboard for how the models compare.
What is the warmest month in Mountainside?
July is typically the warmest month in Mountainside, with average highs around 85°F.
How cold does Mountainside get?
The coldest month in Mountainside is February, when overnight lows average about 23°F.
How much rain does Mountainside get?
Mountainside sees roughly 53 in of precipitation a year, with July usually the wettest month.

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