Skip to content
LuckySap
Get the app
Pennsylvania · county maple atlas

Maple sugaring in Mercer County, Pennsylvania

Mercer County had 25 maple operations and 14,806 taps in the 2022 Census. Around Mercer, sap usually runs from February 21 to March 24. Here's the long-run pattern, 36 seasons of sap weather, and the outlook this week.
Too early to tapAbout 138 days until the usual start.
Sap starts
Feb 21
typical year
Season ends
Mar 24
about 4 weeks
Sap days / season
47.1
1991–2026 average
Taps, 2022
14,806
#9 of 45 in PA

Sap-flow outlook at Mercer right now

Full Pennsylvania forecast →

Forecast for Mercer, PA

Updated Oct 6, 8:36 AM EDT

Off-season for now. Sap needs freezing nights, and none are in sight. Mercer County's season usually opens around February 21, which is 138 days away.

No freeze-thaw days in the forecast

freeze thaw 32°F

  1. WedOct 7
    40° / 72°

    0h below · 24h above

    No refreeze forecast
  2. ThuOct 8
    50° / 69°

    0h below · 24h above

    No refreeze forecast
  3. FriOct 9
    42° / 65°

    0h below · 24h above

    No refreeze forecast
  4. SatOct 10
    43° / 70°

    0h below · 24h above

    No refreeze forecast
  5. SunOct 11
    50° / 70°

    0h below · 24h above

    No refreeze forecast
  6. MonOct 12
    53° / 72°
    No refreeze forecast

Data: National Weather Service. Verdicts use freeze-thaw thresholds from maple field research; your woods may run a little differently.

When the sap runs

The sugaring calendar at Mercer

Freeze-thaw weather at Mercer peaks in the weeks of Jan 26 to Apr 6, which hold about 60% of a season's sap days. March is the busiest month.
Typical season: Feb 21 – Mar 240246Week of Dec 1: 2.2 sap days on averageWeek of Dec 8: 2.5 sap days on averageWeek of Dec 15: 2.3 sap days on averageWeek of Dec 22: 2.1 sap days on averageWeek of Dec 29: 1.6 sap days on averageWeek of Jan 5: 1.6 sap days on averageWeek of Jan 12: 1.7 sap days on averageWeek of Jan 19: 1.2 sap days on averageWeek of Jan 26: 1.9 sap days on averageWeek of Feb 2: 2.3 sap days on averageWeek of Feb 9: 2.1 sap days on averageWeek of Feb 16: 2.4 sap days on averageWeek of Feb 23: 2.6 sap days on averageWeek of Mar 2: 3.1 sap days on averageWeek of Mar 9: 3.1 sap days on averageWeek of Mar 16: 3.0 sap days on averageWeek of Mar 23: 3.0 sap days on averageWeek of Mar 30: 2.6 sap days on averageWeek of Apr 6: 2.2 sap days on averageWeek of Apr 13: 1.3 sap days on averageWeek of Apr 20: 0.9 sap days on averageWeek of Apr 27: 0.7 sap days on averageWeek of May 4: 0.3 sap days on averageWeek of May 11: 0.2 sap days on averageWeek of May 18: 0.0 sap days on averageWeek of May 25: 0.0 sap days on averageDecJanFebMarAprMaytaps in ~Feb 21
Average number of freeze-thaw sap days in each week of the season at Mercer, 1991–2026. A sap day is an overnight low under 30.2 °F followed by an afternoon high over 37.4 °F. The shaded band is the typical season.

Year-to-year spread

Opening signal
Median Feb 16; the middle half of seasons fell between Feb 6 and Feb 26. Earliest Jan 19 (2017), latest Mar 6 (1994).
Closing signal
Median Mar 21; middle half between Mar 9 and Mar 30. Earliest Feb 17 (1998), latest Apr 9 (1994).
Sap days by month
Dec21%Jan15%Feb20%Mar29%Apr14%May1%

36 seasons of sap weather

Mercer County seasons, 1991–2026

The best sap year at Mercer was 2012 with 64 freeze-thaw days; the leanest was 2011 with 32. Seasons that start early tend to end early too: the trees run on the swing between freezing nights and mild days, and heat ends it.
JanFebMarAprMaysap days20262026: Feb 10 – Mar 3, 32 sap days3220252025: Feb 13 – Mar 18, 38 sap days3820242024: Jan 31 – Mar 3, 44 sap days4420232023: Jan 23 – Feb 27, 60 sap days6020222022: Feb 14 – Mar 15, 52 sap days5220212021: Feb 18 – Mar 21, 40 sap days4020202020: Feb 7 – Mar 10, 64 sap days6420192019: Feb 27 – Apr 3, 51 sap days5120182018: Jan 25 – Feb 28, 52 sap days5220172017: Jan 19 – Feb 20, 37 sap days3720162016: Feb 7 – Mar 14, 55 sap days5520152015: Mar 5 – Apr 5, 38 sap days3820142014: Mar 6 – Apr 7, 39 sap days3920132013: Mar 5 – Apr 7, 48 sap days4820122012: Feb 7 – Mar 12, 64 sap days6420112011: Feb 28 – Apr 3, 32 sap days3220102010: Feb 16 – Mar 18, 38 sap days3820092009: Feb 17 – Mar 24, 46 sap days4620082008: Mar 1 – Apr 4, 43 sap days4320072007: Feb 18 – Mar 22, 35 sap days3520062006: Feb 4 – Mar 9, 46 sap days4620052005: Feb 23 – Mar 22, 36 sap days3620042004: Feb 22 – Mar 25, 40 sap days4020032003: Feb 21 – Mar 24, 33 sap days3320022002: Feb 1 – Mar 6, 56 sap days5620012001: Mar 3 – Apr 5, 48 sap days4820002000: Feb 1 – Mar 8, 46 sap days4619991999: Feb 25 – Mar 30, 60 sap days6019981998: Jan 24 – Feb 17, 48 sap days4819971997: Feb 14 – Mar 21, 58 sap days5819961996: Feb 25 – Mar 31, 49 sap days4919951995: Feb 15 – Mar 18, 58 sap days5819941994: Mar 6 – Apr 9, 52 sap days5219931993: Feb 27 – Mar 23, 47 sap days4719921992: Feb 2 – Mar 5, 52 sap days5219911991: Feb 16 – Mar 20, 57 sap days57
Each bar runs from the season's opening signal to its closing signal, estimated from daily temperatures at Mercer. Dashed lines mark the typical dates. The right column counts freeze-thaw sap days from December through May.

Maple production

Mercer County in the Census of Agriculture

USDA counts maple operations every five years. In Mercer County the 2022 Census found 25 farms making syrup (+25% since 2017), with taps +72% and syrup output +46% over the same five years. That works out to about 0.17 gallons of syrup per tap in 2022 (0.20 in 2017). Among the 385 counties in this atlas, Mercer County ranks 109 by taps.

Mercer County maple production, 2017 and 2022 (USDA Census of Agriculture)
Census yearFarmsTapsGallons of syrupGal / tap
20222514,8062,4710.17
2017208,6011,6900.20

Nearby

Neighboring maple counties

Distances are between reference towns; typical dates are each county's own estimate.

About these numbers

The season dates are estimated from 36 seasons of daily high and low temperatures for the PRISM 4-km grid cell at Mercer (1,161ft), scored with the same freeze-thaw rule as our live forecast: a sap day is an overnight low under 30.2 °F followed by an afternoon high over 37.4 °F. Each season's closing signal is the last sap day before accumulated warmth reaches a threshold, and the opening signal sits five weeks before that, never earlier than the first real freeze-thaw week. Tested against 117 state-seasons of USDA-reported dates, the rule lands within 5.5 days of the reported close and 6.6 days of the reported opening on average, and the typical dates shown here are scaled to Pennsylvania's USDA record (12 years). Production figures are copied from the Census as published. Full method, calibration tables and the downloadable dataset →

Sources · 6

  1. 1.2022 Census of Agriculture, County Level Data — Pennsylvania, Table 37: Maple Syrup, 2022 and 2017 · USDA National Agricultural Statistics Service
  2. 2.PRISM daily temperature grids (AN81d, 4 km), accessed 2026-10-05 · PRISM Group, Oregon State University, https://prism.oregonstate.edu
  3. 3.Applied Climate Information System (ACIS) web services · NOAA Regional Climate Centers
  4. 4.USDA NASS maple syrup reports — approximate average season opened and closed dates, 2011–2022 · USDA National Agricultural Statistics Service (mirrored by the University of Vermont)
  5. 5.Sap flow in sugar maple: timing and weather drivers (Frontiers in Agronomy, 2025) · de Lima Santos et al.
  6. 6.GeoNames gazetteer (cities500), CC BY 4.0 · GeoNames

FAQ

Mercer County sugaring questions

When should I tap maple trees in Mercer County, Pennsylvania?
In a typical year the sap starts running around February 21 near Mercer and the season winds down around March 24. Have your taps in a day or two before the first forecast string of freezing nights and 40 °F days. In the past 36 seasons the weather signal came as early as Jan 19 and as late as Mar 6.
How much maple syrup does Mercer County produce?
The 2022 Census of Agriculture counted 25 maple operations in Mercer County with 14,806 taps producing 2,471 gallons of syrup, ranking 9 of 45 Pennsylvania's counties with published tap counts.
How many sap days does Mercer County get in a season?
On average 47.1 freeze-thaw sap days from December through May at Mercer, of which about 14 are textbook days with a night in the 20s and a day in the 40s. The best season since 1991 was 2012 (64 sap days); the leanest was 2011 (32).
Where do these dates come from?
From 36 seasons of daily high and low temperatures at Mercer (PRISM 4-km grid), scored with the same freeze-thaw rule as our live forecast, then calibrated against USDA's reported season dates for Pennsylvania. They describe a typical year at one point in the county; your sugarbush, slope and elevation can shift them by days.

LuckySap · free on iPhone & Android

Get a heads-up when the sap will run in Mercer County

LuckySap watches the forecast for your trees and can ping you the night before a strong sap day, then keeps every collection and boil in one season log. Free on iPhone and Android.

Download on the App StoreGet it on Google Play