Holtsville, New York Weather
Cicadas claim the afternoon. Day 14 of summer. Read this microseason across nine climate regions →
Holtsville weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 4Overcast36%—97°76°—
- SundayJul 5Heavy Rain42%4.2″86°71°-11°
- MondayJul 6Light Showers84%0.15″71°68°-15°
- TuesdayJul 7Light Drizzle81%0.03″71°63°0°
- WednesdayJul 8Overcast23%—80°63°+9°
- ThursdayJul 9Light Drizzle——85°70°+5°
- FridayJul 10Overcast36%—92°72°+7°
AQI 103 (Unhealthy for Sensitive Groups), driven by Ozone. AQI up 49 in the last 6 hours — air quality is degrading. Ozone at AQI 159 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
CAUTION Sensitive groups (children, elderly, respiratory conditions) should limit prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 159 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 159
- UV peak
- 3.5 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 159
PM × Wind × Precip
PM2.5 at 14.7 µg/m³, PM10 at 17.1 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.86
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 10:47 PM
- Moonset
- 9:54 AM
- In sign
- ♓︎ Pisces
Cicadas claim the afternoon
Holtsville at a glance
- Today vs. normal: 25°F above the seasonal normal for this latitude
- Last frost: April 21 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 11742
16-Day Forecast — Holtsville
- Sat97°76°36%
- Sun86°71°42%
- Mon71°68°84%
- Tue71°63°81%
- Wed80°63°23%
- Thu85°70°9%
- Fri92°72°36%
- Sat92°76°36%
- Sun86°71°20%
- Mon74°67°20%
- Tue78°65°19%
- Wed86°64°25%
- Thu91°73°45%
- Fri93°72°35%
- Sat91°76°27%
- Sun92°78°42%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 4, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
SPC Convective Outlook
Storm Prediction Center — Holtsville
SPC has placed Holtsville in the Slight Risk category for severe thunderstorms today.
- TODAYSLGTSlight Risk
- TOMORROWMRGLMarginal Risk
- DAY 3TSTMGeneral Thunderstorms
Scattered severe storms possible. A few tornadoes, hail, and damaging wind gusts possible.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
Beaches near Holtsville
- Robert Moses Beach17.5 mi
- Jones Beach28.5 mi
Each linked page shows live water temperature, wave height, swim and surf verdicts, tides, and rip-current risk from NDBC + NOAA + NWS data.
ZIP codes in Holtsville
- 11742
- 00501
- 00544