Fall in zone 6bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 16638 (Huntingdon County, PA)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Altoona Blair Co AP, PA (7 miles away).
- Average last spring frostApr 2350% chance of a 32°F freeze after this date
- Average first fall frostOct 2150% chance of a 32°F freeze by this date
- Growing season (frost-free)177 daysmedian, 32°F threshold
- USDA hardiness zone6b-5 to 0°F avg. coldest night
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This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
55°F 55°F or warmer
24-hour average · latest 51°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Rock Springs Pa (30 mi).
4-inch depth
58°F 55°F or warmer
24-hour average · latest 54°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Rock Springs Pa (30 mi).
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 16638 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 58°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent (annual bluegrass, winter weeds): window open as soil cools through the 70s and 60s.
Fertilizer window
Lawn region: North (cool-season). Timing only; always follow the product label.
- Kentucky bluegrass (cool-season): Early fall: Around Labor Day (late August–September); Late fall: Late October–November, before the ground freezes; Late spring: Optional around Memorial Day. Avoid: Early-spring and midsummer feeding (pushes top growth, favors crabgrass).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Oct 21: skip heavy pruning in the 6–8 weeks before it, because new growth may not harden off in time.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Apr 8 |
| 50% (the "average" last frost) | Apr 23 |
| 10% (cautious: only 1 year in 10 freezes later) | May 11 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Oct 5 |
| 50% (the "average" first frost) | Oct 21 |
| 90% (late: most years have frozen by now) | Nov 4 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 4 | Oct 7 |
| 32°F (freeze) | Apr 23 | Oct 21 |
| 28°F (hard freeze) | Apr 11 | Nov 1 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 16638
Dates count from your average last spring frost (Apr 23) and first fall frost (Oct 21). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Feb 26–Mar 12 | Apr 30–May 14 (transplant) | – |
| Pepper (sweet and hot) | Feb 12–26 | May 7–21 (transplant) | – |
| Eggplant | Feb 12–26 | May 7–21 (transplant) | – |
| Tomatillo | Feb 26–Mar 12 | Apr 30–May 14 (transplant) | – |
| Lettuce | Feb 26–Mar 12 | Apr 2–23 (transplant) Mar 26–May 7 (sow outdoors) | Aug 26–Sep 16 (transplant) Aug 12–Sep 9 (sowing) |
| Spinach | – | Mar 12–Apr 2 (sow outdoors) | Aug 26–Sep 16 (sowing) |
| Kale | Feb 26–Mar 12 | Mar 26–Apr 9 (transplant) Mar 26–Apr 9 (sow outdoors) | Jul 29–Aug 26 (transplant) Jul 15–Aug 12 (sowing) |
| Collards | Feb 26–Mar 12 | Mar 26–Apr 23 (transplant) Mar 26–Apr 23 (sow outdoors) | Jul 29–Aug 26 (transplant) Jul 15–Aug 12 (sowing) |
| Broccoli | Feb 12–26 | Mar 26–Apr 9 (transplant) | Jul 15–Aug 12 (transplant) |
| Cabbage | Feb 12–26 | Mar 26–Apr 9 (transplant) | Jul 15–Aug 12 (transplant) |
| Cauliflower | Feb 12–26 | Apr 9–23 (transplant) | Jul 15–Aug 12 (transplant) |
| Brussels sprouts | Jan 29–Feb 12 | Mar 26–Apr 9 (transplant) | Jul 1–22 (transplant) |
| Kohlrabi | Feb 26–Mar 12 | Mar 26–Apr 9 (transplant) Mar 26–Apr 9 (sow outdoors) | Aug 12–26 (sowing) |
| Bok choy / Asian greens | – | Mar 26–Apr 9 (sow outdoors) | Aug 26–Sep 9 (sowing) |
| Arugula | – | Mar 26–Apr 23 (sow outdoors) | Aug 26–Sep 23 (sowing) |
| Mustard greens | – | Mar 26–Apr 16 (sow outdoors) | Aug 26–Sep 9 (sowing) |
| Swiss chard | Mar 12–26 | Apr 9–30 (transplant) Apr 9–May 7 (sow outdoors) | Aug 12–26 (sowing) |
| Beet | – | Mar 26–Apr 23 (sow outdoors) | Aug 12–26 (sowing) |
| Carrot | – | Apr 2–30 (sow outdoors) | Jul 29–Aug 12 (sowing) |
| Radish | – | Mar 19–Apr 30 (sow outdoors) | Sep 9–23 (sowing) |
| Turnip | – | Mar 26–Apr 16 (sow outdoors) | Aug 12–26 (sowing) |
| Parsnip | – | Apr 2–23 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 26–Mar 26 (sow outdoors) | Jul 29–Aug 12 (sowing) |
| Onion (bulbing) | Jan 29–Feb 12 | Mar 12–26 (transplant) | – |
| Green onion / scallion | – | Mar 12–Apr 9 (sow outdoors) | Aug 12–26 (sowing) |
| Leek | Jan 29–Feb 12 | Mar 26–Apr 9 (transplant) | – |
| Garlic | – | – | Sep 9–Oct 7 (sowing) |
| Shallot | – | Mar 12–26 (transplant) | Sep 9–Oct 7 (sowing) |
| Potato | – | Mar 26–Apr 9 (transplant) | Jul 1–15 (transplant) |
| Sweet potato | – | May 14–28 (transplant) | – |
| Sweet corn | – | Apr 30–May 14 (sow outdoors) | – |
| Bean, bush (snap) | – | Apr 30–May 14 (sow outdoors) | – |
| Bean, pole | – | Apr 30–May 14 (sow outdoors) | – |
| Lima bean | – | May 7–21 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 14–Jun 4 (sow outdoors) | – |
| Cucumber | Mar 26–Apr 2 | Apr 30–May 14 (transplant) Apr 30–May 14 (sow outdoors) | – |
| Summer squash / zucchini | Mar 26–Apr 2 | Apr 30–May 14 (transplant) Apr 30–May 14 (sow outdoors) | – |
| Winter squash | Mar 26–Apr 2 | Apr 30–May 14 (transplant) Apr 30–May 14 (sow outdoors) | – |
| Pumpkin | – | Apr 30–May 14 (sow outdoors) | – |
| Watermelon | Mar 26–Apr 2 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 26–Apr 2 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Okra | Mar 12–26 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Celery | Jan 29–Feb 12 | Apr 30–May 7 (transplant) | – |
| Basil | Mar 12–26 | Apr 30–May 14 (transplant) Apr 30–May 14 (sow outdoors) | – |
| Cilantro | – | Apr 9–May 7 (sow outdoors) | Aug 26–Sep 9 (sowing) |
| Parsley | Feb 12–26 | Apr 9–23 (transplant) Apr 2–23 (sow outdoors) | – |
| Dill | – | Apr 23–May 7 (sow outdoors) | Aug 26–Sep 9 (sowing) |
| Sunflower | – | Apr 23–May 7 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 26–Apr 9 (transplant) | – |
| Rhubarb (crowns) | – | Mar 26–Apr 9 (transplant) | – |
| Strawberry (plants) | – | Mar 26–Apr 9 (transplant) | Aug 12–Sep 9 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Altoona Blair Co AP, PA (NOAA GHCN-Daily ID USW00014736), elevation 1,480 ft, 6.9 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Raystown Lake 2, PA | 7 mi | Apr 19 | Oct 28 |
| Raystown Hq, PA | 7 mi | Apr 19 | Oct 29 |
| Altoona 7 SW, PA | 13 mi | Apr 25 | Oct 20 |
The average last-frost dates of these stations span 6 days, a rough guide to local variation. See data sources & methods.
Frost questions for 16638
When is the last frost in 16638?
The average (50% chance) last spring freeze of 32°F for ZIP 16638 is April 23. For a more cautious planting date, use May 11, when only 1 year in 10 still sees a later freeze.
When is the first frost in 16638?
The average first fall freeze is October 21. In 1 year in 10 it comes by October 5.
What hardiness zone is 16638?
ZIP 16638 is in USDA zone 6b (-5 to 0°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 16638 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
16657 Marklesburg 16647 16662 Martinsburg 16622 16621 Broad Top City 16685 16678 Saxton 16693 Yellow Springs
Other ZIP codes in Huntingdon County
16611 16621 16622 16623 16634 16647 16652 16654 16657 16669 16674 16683 16685 16694 17002 17052 17060 17066 17213 17215 17239 17243 17249 17253 All Huntingdon County frost dates · Pennsylvania frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
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Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.