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Will it freeze in Porter in the next 7 nights?
No overnight lows at or below 32°F are forecast in Porter during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 44°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
1 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 44°F Above 36°F · Rain Showers then Slight Chance Rain
- Fri, Nov 6 41°F Above 36°F · Chance Rain Showers
- Sat, Nov 7 36°F Frost possible · Mostly Clear
- Sun, Nov 8 40°F Above 36°F · Mostly Clear
- Mon, Nov 9 45°F Above 36°F · Clear
- Tue, Nov 10 43°F Above 36°F · Partly Cloudy
- Wed, Nov 11 42°F Above 36°F · Partly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Porter
The median first fall hard-freeze date (28°F) is November 7, from NOAA’s 1991–2020 Climate Normals at Indiana Dunes Nl. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Apr 20 · May 4 · May 21 | Oct 4 · Oct 16 · Oct 30 | 164 days |
| 32°F freeze | Apr 7 · Apr 22 · May 8 | Oct 15 · Oct 27 · Nov 9 | 188 days |
| 28°F hard freeze | Mar 26 · Apr 8 · Apr 23 | Oct 26 · Nov 7 · Nov 25 | 213 days |
Average high temperature by month
1991–2020 normals at Indiana Dunes Nl
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Porter, IN come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Indiana Dunes Nl (station USC00124244, elevation 680 ft), 0.4 mi from Porter. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Porter
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Chesterton, IN | 2.5 mi | Apr 22 | Oct 27 |
| Portage, IN | 5.6 mi | Apr 22 | Oct 27 |
| Lake Station, IN | 9.3 mi | Apr 22 | Oct 27 |
| Valparaiso, IN | 11 mi | Apr 22 | Oct 25 |
| Westville, IN | 11 mi | Apr 29 | Oct 13 |
| Michigan City, IN | 12 mi | Apr 19 | Oct 27 |
| Hobart, IN | 13 mi | Apr 22 | Oct 25 |
| Gary, IN | 14 mi | Apr 22 | Oct 27 |
| Merrillville, IN | 16 mi | Apr 22 | Oct 25 |
| Winfield, IN | 17 mi | Apr 29 | Oct 16 |
Frequently asked questions
When is the last frost in Porter?
On average, the last spring frost (32°F) in Porter is around April 22. In about 1 year in 10 it comes after May 8, and in 9 years in 10 it comes after April 7.
When is the first frost in Porter?
The first fall frost (32°F) usually arrives around October 27. There’s a 10% chance of a freeze by October 15 and a 90% chance by November 9.
Can it frost in Porter after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 4.
What growing zone is Porter?
Porter is in USDA Plant Hardiness Zone 6a (average annual extreme minimum temperature −10 to −5°F), based on the 2023 USDA map for ZIP code 46304. See growing zones in Indiana.
More: all Indiana frost dates · Indiana growing zones · frost vs. freeze