Last updated: January 25, 2021
Article
2019 Weather in Review: Colonial National Historical Park
Weather and climate play significant roles in driving both physical and ecological processes. For example, the active processes that shape the North Atlantic shoreline are largely the result of meteorological events such as wind-driven waves. For research and long-term ecological monitoring, weather and climate data provide the potential for correlations to be made with observed physical and ecological pattern data.
This resource brief provides a summary of both historic and current (2019) weather and water level data for Colonial National Historical Park, Virginia (VA). Because tide levels are significant for coastal parks, the annual water level data are included. Information in this brief represents county-scale weather data averaged from all of the counties surrounding the park units. These counties include James City and York counties, VA. Individual weather station data may vary from what is reported here. Data are available from the National Climate Data Center.
Temperature
James City County
Overall, 2019 was the warmest year on record, with an average temperature of 61.2 °F — 2.6 degrees higher than the average annual temperature (Figure 1). Seasonally, autumn and winter fell with “above normal” temperatures, while both spring and summer fell within “much above normal” temperatures. Five months had greater than 4 degrees above the average monthly temperature, including February, April, May, September, and October, with May having the greatest increase in temperature at 6.3 degrees above average. Only March and November had lower than average monthly temperatures (Table 1).
| Month (2019) |
Average temperature (°F) | Departure from long-term average temperature (°F) |
| January | 39.9 | +1.3 |
| February | 44.6 | +4.5 |
| March | 47.2 | -0.9 |
| April | 62.2 | +5.1 |
| May | 72.8 | +6.3 |
| June | 75.6 | +1.2 |
| July | 80.9 | +2.4 |
| August | 78.6 | +1.6 |
| September | 75.6 | +4.4 |
| October | 64.9 | +4.6 |
| November | 47.1 | -2.7 |
| December | 45.1 | +4.0 |
| Annual | 61.2 | +2.6 |
York County
Overall, 2019 was the 2nd warmest year on record, with an average temperature of 61.5 °F — 2.7 degrees above the average annual temperature (Figure 2). Seasonally, autumn and winter fell within “above normal” temperatures, while both spring and summer reached “much above normal” temperatures. Five months had greater than 4 degrees above the average monthly temperature, including February, April, May, October, and December, with May having the greatest increase in temperature at 6.3 degrees above average. Only March and November had lower than average monthly temperatures (Table 2).
| Month (2019) |
Average temperature (°F) | Departure from long-term average temperature (°F) |
| January | 40.4 | +1.4 |
| February | 45.1 | +4.8 |
| March | 47.4 | -0.7 |
| April | 62.3 | +5.2 |
| May | 72.8 | +6.3 |
| June | 75.8 | +1.3 |
| July | 81.0 | +2.4 |
| August | 78.7 | +1.6 |
| September | 75.5 | +4.0 |
| October | 65.4 | +4.7 |
| November | 47.7 | -2.5 |
| December | 45.9 | +4.3 |
| Annual | 61.5 | +2.7 |
Precipitation
James City County
Overall, 2019 was the 38th wettest year on record with a total of 48.32 inches of precipitation (Figure 3, Table 3). Seasonally, winter, spring, and autumn had precipitation levels “above normal” amounts while summer fell to a “below normal” level. Half of the months had a higher average monthly precipitation average, while the other half had lower. June was the wettest month at 3.30 inches above average, and September was the driest month at -3.03 inches below average.
| Month (2019) |
Total precipitation (in) | Departure from long-term average precipitation (in) |
| January | 3.43 | +0.03 |
| February | 4.44 | +1.30 |
| March | 3.85 | -0.03 |
| April | 4.03 | +0.74 |
| May | 3.12 | -0.79 |
| June | 7.47 | +3.30 |
| July | 4.85 | -0.37 |
| August | 4.59 | -0.17 |
| September | 0.86 | -3.03 |
| October | 5.52 | +2.35 |
| November | 2.72 | -0.11 |
| December | 3.44 | +0.17 |
| Annual | 48.32 | +3.38 |
York County
Overall, 2019 was the 41st wettest year on record, with 47.24 inches of precipitation (Figure 4, Table 4). Seasonally, winter, spring, and autumn had precipitation levels “above normal,” while summer fell to a “below normal” level. Seven months had higher monthly average levels of precipitation. June was the wettest month with 2.71 inches above average, and September was the driest month with 2.64 inches below average.
| Month (2019) | Total precipitation (in) | Departure from long-term average precipitation (in) |
| January | 3.55 | +0.17 |
| February | 4.51 | +1.29 |
| March | 3.81 | -0.07 |
| April | 4.35 | +1.10 |
| May | 3.02 | -0.78 |
| June | 6.79 | +2.71 |
| July | 4.53 | -0.77 |
| August | 4.54 | -0.29 |
| September | 1.27 | -2.64 |
| October | 5.03 | +1.85 |
| November | 2.67 | -0.14 |
| December | 3.17 | -0.12 |
| Annual | 47.24 | +2.31 |
Temperature and Precipitation Trends (1895–2019)
Temperature and precipitation data are gathered from the U.S. Climate Divisional Database, which stores data from January 1895 through 2019, and can be accessed via the National Oceanic and Atmospheric Administration’s (NOAA) National Centers for Environmental Information (NCEI) website (Figures 5 and 6). Users can choose different geographic scales (i.e., global, national, statewide), different temporal scales, and display them in various types of graphical formats. Temperature and precipitation data presented in this brief are for James City and York Counties, VA.
Left image
Figure 5. James City County, Virginia yearly average temperature and precipitation from 1895 to 2019. Dashed lines represent the 1895-2019 trend for each parameter; +0.1°F/decade for temperature and +0.46 in/decade for precipitation.
Right image
Figure 6. York County, Virginia yearly average temperature and precipitation from 1895 to 2019. Dashed lines represent the 1895-2019 trend for each parameter; +0.1°F/decade for temperature and +0.47 in/decade for precipitation.
Wind
Wind-generated waves can impact shorelines differently depending on wind speed and direction. Wind data are collected from a weather station at Williamsburg Jamestown Airport, VA, and made available through NOAA's NCEI (Figure 7). The Yorktown website Training Center tide gauge also collects wind data but was offline for the majority of 2019. Therefore, corresponding data are not present in this brief but will be incorporated in the 2020 Weather in Review.
Tide Levels
The extent of Colonial National Historical Park’s shoreline falls along the James and York Rivers, and each has unique tidal characteristics. Therefore, two sources of water level data are used to reflect this dynamic. Water level data are obtained from NOAA station 8637712 located at Jamestown Ferry Wharf, VA, and from NOAA station 8637689 located at the Yorktown U.S. Coast Guard (USCG) Training Center, VA. The station at Jamestown Ferry Wharf began collecting data in 2010, while the station at USCG Training Center has records dating back to 2004.
The data are graphed to show the difference in the predicted tide level versus what was observed (Figures 8 and 9). The offsets in height reflect the effect of storm surge on the normal, astronomically driven tide level.
Left image
Figure 8. The difference in the predicted and observed tide levels at Jamestown Ferry Wharf, Jamestown, Virginia for 2019.
Right image
Figure 9. The difference in the predicted and observed tide levels at the Yorktown U.S. Coast Guard Training Center, Virginia for 2019.