Chesapeake Bay Climate Impacts Summary and Outlook

Mid-Atlantic Regional Climate Impacts Summary and Outlook: Fall 2024

Highlights

  • Conditions were generally hotter and drier than normal across the Mid-Atlantic for the fall 2024 season.
  • Average temperatures for the 2024 fall season were 2-4 degrees F above normal for most of the Mid-Atlantic region. This is slightly warmer than the temperature departures in the summer 2024 season.
  • Five sites experienced fall seasons that ranked in their top five warmest on record, largely due to November being a particularly warm month. Washington, D.C., saw its warmest November on record.
  • Eastern portions of the region received only 25-50 percent of normal precipitation and only portions of southern and western Virginia and southeastern West Virginia saw above normal amounts of precipitation.
  • Several sites experienced their longest streak of consecutive days without measurable precipitation (defined as at least 0.01 inches). This included Baltimore, Maryland, and Dulles Airport, Virginia, which did not see measurable precipitation for 38 straight days (October 3–November 9). Meanwhile, record-long streaks were also set at Salisbury, Maryland (39 days from October 2–November 9), Norfolk, Virginia (36 days from October 3–November 7), and Martinsburg, West Virginia (33 days from October 8-November 9).
  • When comparing climate model projections for the Mid-Atlantic, we found that the CMIP6 models generally project wetter conditions compared to the CMIP5 models, with parts of Western Pennsylvania and Western Virginia potentially seeing twice as many extreme precipitation days in the new projections. We saw minimal differences between the projections when looking at temperatures across the region.

View all climate summaries

This summary focuses on fall weather and climate events in the Chesapeake Bay watershed and provides highlights from the greater Mid-Atlantic region. The fall season is defined as the months of September, October, and November. The MARISA region covers Maryland, Delaware, Virginia, and Pennsylvania and the portions of New York and West Virginia that fall within the boundaries of the Chesapeake Bay watershed, as shown in Figure 1 below. We refer to this region as the Mid-Atlantic region in the rest of the climate summary.

Figure 1. MARISA Mid-Atlantic Region

A map of the Mid-Atlantic regional highlighting the Chesapeake Bay watershed.

This map shows the “MARISA region”. The lightly shaded area shows the extent of the Chesapeake Bay Watershed.

Part 1: Significant Weather Events and Impacts

Severe Weather

From November 20 to 22, a complex storm system brought much-needed precipitation to the watershed.1 While rain was generally the prevalent precipitation type, most places reported at least some snowfall, with lower elevations seeing little but some higher elevations seeing six or more inches of snow.2,3 One of the greatest snowfall totals of the storm was 20.5 inches in Lackawanna County, Pennsylvania.4 Meanwhile, November 22 became one of the 10 snowiest November days on record for Scranton, Pennsylvania, and Binghamton, New York, which saw 10.7 and 7.3 inches respectively.5

Drought

The U.S. Drought Monitor from September 3 showed severe and/or moderate drought in an area stretching from western Virginia into south-central Pennsylvania, encompassing portions of eastern West Virginia, western/central Maryland, and northern Virginia.6 Abnormal dryness surrounded this area and stretched into central Virginia, southern/eastern Maryland, and parts of Delaware.7 Limited rainfall during the first half of September led to the expansion of drought and dryness in the southern parts of the watershed, with extreme drought creeping into the western edge of the region.8 During the second half of the September, much of Virginia and portions of eastern West Virginia saw heavy rainfall, particularly from the remnants of Hurricane Helene (discussed below), allowing drought and dryness to contract.9 However, much of the rest of the watershed was drier than normal, which allowed drought and dryness to expand.

During the first half of September, streamflow and soil moisture were below normal in the southern parts of the watershed.10,11 The lower-than-normal water levels slowed recreational activities and tourism in parts of Virginia, resulting in reduced revenue for some businesses.12 However, streamflow and soil moisture levels were boosted in areas that saw notable rainfall during the second half of the month.13,14 Despite this improvement in surface conditions, recovery of groundwater levels generally lagged.15 Trees in western Maryland were stressed by drought conditions, leading to premature leaf drop, earlier-than-usual color changes, and muted colors.16

Historically dry weather in October led to deteriorating conditions in much of the watershed, with several sites experiencing their longest streak of consecutive days without measurable precipitation (see Part 2 for details).17,18 For instance, severe drought was introduced in Delaware and eastern Maryland, while moderate drought expanded in southern Pennsylvania, Maryland, and northern and eastern Virginia.19 Meanwhile, an area of extreme drought surrounded by severe and moderate drought persisted in western Maryland and eastern West Virginia.20 Abnormal dryness expanded in Virginia, Pennsylvania, and New York.21

During October, especially during the second half of the month, streamflow and/or groundwater levels were record low in places like southern/eastern Maryland and parts of Delaware.22 Mandatory water restrictions were enacted in a few communities in central Pennsylvania, and residents in multiple parts of the watershed were asked to conserve water.23,24,25 Topsoil moisture declined rapidly in parts of the watershed. For instance, U.S. Department of Agriculture (USDA) data for the week ending on October 27 showed 98 percent of Delaware's agricultural lands and 91 percent of Maryland's having topsoil moisture in the driest two categories (very short, short), a 33 percentage point increase in just a week in Maryland (from 58% to 91%).26 A press release from Delaware officials noted, "Presently some soils are so dry that cover crops and small grains that are being seeded do not have enough moisture to germinate. These crops are important to help retain nutrients thereby protecting groundwater and surface waters. If they can't be established, we lose that ability."27 This same press release also mentioned that water conservation alone cannot address all the agricultural impacts of the lack of rainfall.28

USDA data for the week ending October 27 also showed pasture and rangeland conditions worsened in Maryland, being in the worst two categories (poor or very poor) for 57 percent of the state's agricultural lands.29 Grain harvest continued in October, with corn yields below average due to dry conditions during the growing season in parts of Delaware, Maryland, and Virginia.30 The supply of Christmas trees may be reduced this upcoming holiday season.31 A farm in eastern Maryland noted that drought conditions wiped out hundreds of trees.32

The first half of November was warm and dry, allowing drought to expand and intensify in the watershed.33 However, the second half of the month featured more precipitation for most areas, slowing the deterioration in some locations and improving conditions in a few spots.34 During the month, extreme drought was introduced in eastern Maryland and central Delaware but improved in eastern West Virginia and western Maryland.35 Similarly, severe and moderate drought expanded westward and northward in the watershed, but moderate drought shrank in coverage in southeastern Virginia.36 The fall season started with only 18 percent of the state of Maryland in drought including 10 percent in severe drought or worse conditions.37 Based on the November 26 U.S. Drought Monitor, autumn wrapped up with all of Maryland in drought including 75 percent of the state experiencing severe drought or worse conditions.38

Streamflow continued to be lower than normal in the watershed, raising concerns about water supplies for rural firefighting operations in Pennsylvania.39,40 Below-normal streamflow on the Potomac River played a role in the Drought Watch being extended for the Washington, D.C. area.41,42 Several water suppliers in central Pennsylvania enacted mandatory water restrictions, while residents in many other areas were asked to voluntarily conserve water.43,44,45 In early November, some growers continued to irrigate crops, which is unusually late in the season.46 There were more reports of damage to Christmas trees, including over 1,000 trees that died on a farm in Frederick County, Maryland, resulting in at least $10,000 in losses for the 100 trees that could have been sold this year.47,48

Figure 2. U.S. Drought Monitor for the Mid-Atlantic

Animation showing areas of drought in the Mid-Atlantic region from September to November, 2024. Source: U.S. Drought Monitor

SOURCE: U.S. Drought Monitor

Wildfires

Little precipitation in September contributed to an increased risk of wildfires in Delaware.49

Fire danger was high across much of the watershed, with the Maryland Forest Service responding to three times more fires this October compared to the 10-year average.50 Statewide burn bands were enacted in Delaware, Maryland, and West Virginia.51,52,53 Meanwhile, several counties and municipalities in parts of Pennsylvania and New York issued burn bans.54,55

Pennsylvania saw at least 100 wildfires in just the first week of November, with the state seeing more fires this fall than during the entire spring fire season.56 In fact, many areas saw an uptick in wildfire activity, with fires burning deeper making them harder to extinguish.57 Wildfire smoke led to reduced air quality and hazy skies in some areas.58 Burn bans were enacted or remained in place in multiple locations through much of November.59,60,61 However, beneficial precipitation later in the month allowed some of these bans to be lifted.62,63,64,65

Tropical Storms

On September 24 and 25, a storm system near the western edge of the watershed brought rain to the region.66 The greatest rainfall amounts were in Virginia, where flooding caused mudslides and road closures in several counties in the northwestern part of the state.67,68 This storm system stalled over the Ohio Valley, wrapping in moisture from approaching Hurricane Helene on September 26 and merging with Helene on September 27, bringing heavy rainfall to the southern portion of the Mid-Atlantic region.69 With the heavy rain falling on top of waterways that were already running higher than normal due to the rainfall from earlier in the week, more flooding occurred.70 For instance, in Augusta County, Virginia, multiple roads were closed, vehicles were stranded, and some residents were urged to evacuate.71 Additionally, gusty winds in western Virginia downed dozens of trees and power lines, leading to power outages and resulting in a fatality.72,73

This combined storm meandered from the Ohio Valley across the Mid-Atlantic between September 28 and October 1, bringing more rainfall and continued flooding and road closures.74,75,76

For the entire September 25 to October 1 period, the greatest rainfall totals within the watershed exceeded 15 inches in central Virginia.77 Floodwaters from upstream such as western North Carolina made their way through the watershed, further increasing water levels in portions of the region.78,79 Additional storm impacts in the watershed included prolonged road closures, crop losses, and polluted waterways.80,81,82 However, the excessive rainfall eased drought conditions in some areas.83

Helene also produced devastating damage, primarily from flooding, just outside the watershed in southwestern Virginia, where hundreds of homes were damaged, roads were wiped away, crop losses likely exceeded $125 million, and at least two people died.84,85,86,87

Tidal Flooding

Communities along the Chesapeake Bay shoreline saw higher-than-normal water levels from around September 17-24 as a stalled non-tropical storm along the coast of South Carolina coincided with king tides.88,89,90 For instance, the tidal gauge along the Chesapeake Bay at Bishops Head, Maryland, reached its fifth-highest water level in its 20-year period of record.91 The high water flooded yards and roads, limiting travel and affecting schools including those in Somerset County, Maryland, which were closed for two days.92,93,94

Figure 3. Tidal Flooding in Crisfield, Maryland, on September 22, 2024.

A flooded road in Crisfield, Maryland, on September 22, 2024. Photo: MyCoast.org. Photo courtesy of MyCoast.org

SOURCE: MyCoast.org

Part 2: Seasonal Temperature and Precipitation

Temperature

Figure 4 shows the fall 2024 average temperature compared with the climate normal—i.e., the average seasonal temperature from 1991 to 2020.95 The figure shows that the entire region experienced above normal temperatures this season. Most of the region experienced temperatures that were 2-4 degrees F above normal, with a few locations experiencing temperatures a few degrees warmer or cooler than that. This is slightly warmer than the temperature departures in the Summer 2024 season.

Figure 4. September 1 – November 30, Departure from Normal Temperature (degrees Fahrenheit)

A heat map showing departure from normal temperature in the Mid-Atlantic region from September to November, 2024. Northeast Regional Climate Center

SOURCE: Northeast Regional Climate Center, 2024 (https://www.nrcc.cornell.edu). Used with permission.

Normal temperature is based on the fall season's average temperature data from 1991–2020. Shades of red indicate above-normal temperatures. Shades of blue indicate below-normal temperatures. The boundaries of the Chesapeake Bay watershed are outlined in bold black. Average departure from normal temperature is based on a station's normal temperature for fall compared with the same station's fall 2024 average temperature. Station-level departures from normal are spatially interpolated across the region. Both are produced by the Northeast Regional Climate Center. These can be found at https://www.rcc-acis.org/docs_gridded.html.

Table 1. Fall Season (September–November) Temperature Rankings

Station Name Avg. Temp (degrees F) Normal Temp (degrees F) Rank (warmest)
Washington National, DC 63.6 61.0 2
Richmond, VA 63.1 60.2 4
Binghamton, NY 51.5 48.9 5
Dulles Airport, VA 59.4 57.1 5
Scranton, PA 55.5 53.5 5
Norfolk, VA 65.2 63.6 9
Harrisburg, PA 58.0 56.2 12
Lynchburg, VA 60.0 57.1 12
Williamsport, PA 55.4 53.2 12
Martinsburg, WV 56.8 55.5 20

SOURCE: Northeast Regional Climate Center, 2024 (https://www.nrcc.cornell.edu). Used with permission.

NOTE: In this table, "avg. temp" is the temperature average from the spring season, while the "normal temp" is the 30-year average (from 1991-2020) for spring temperatures.

Monthly Temperature Rankings

September 2024 ranked among the 20 warmest months of September on record for two sites and a slightly warm October 2024 just barely ranked among the 20 warmest months of October on record for four sites (Table 2).

Baltimore, Maryland had its ninth earliest first fall frost on October 17 with a low of 32 degrees F and Binghamton, while New York experienced its eighth latest first fall frost, not dropping to 31 degrees F until October 25.96

The first week of November was unusually warm, with high temperatures in the 70s and 80s and low temperatures in the 50s and 60s. Several sites including Baltimore, Maryland, Harrisburg, Pennsylvania, and Binghamton, New York saw high and/or low temperatures that ranked among the 10 warmest for November, in some cases for multiple days.97 For example, Scranton, Pennsylvania had its sixth warmest and tenth warmest high temperatures for November along with its fifth warmest low temperature for November.98 These warm temperatures were reflected in the monthly rankings, with most sites in the watershed experiencing one of their top 20 warmest months of November on record. It was particularly warmer than normal in Washington, D.C., which saw its warmest November on record.

The full set of monthly rankings, locations, and temperatures are shown in Table 2.

Table 2. Monthly Temperature Rankings

September Temperature Rankings (warmest)
Station Name Avg. Temp (degrees F) Normal Temp (degrees F) Rank (warmest)
Scranton, PA 66.2 64.6 12
Binghamton, NY 62.1 60.0 17
October Temperature Rankings (warmest)
Station Name Avg. Temp (degrees F) Normal Temp (degrees F) Rank (warmest)
Dulles Airport, VA 58.2 56.6 17
Washington National, DC 63.0 60.8 17
Binghamton, NY 51.2 48.8 18
Richmond, VA 62.4 60.0 19
November Temperature Rankings (warmest)
Station Name Avg. Temp (degrees F) Normal Temp (degrees F) Rank (warmest)
Washington National, DC 55.2 49.9 1
Dulles Airport, VA 51.0 46.0 3
Norfolk, VA 58.3 53.3 3
Richmond, VA 54.7 49.6 3
Lynchburg, VA 51.9 46.5 7
Harrisburg, PA 48.3 44.8 9
Binghamton, NY 41.3 37.9 12
Baltimore, MD 50.8 46.9 14
Martinsburg, WV 48.4 44.6 14
Scranton, PA 45.4 42.7 15
Charlottesville, VA 51.3 49.1 17

SOURCE: Northeast Regional Climate Center, 2024 (https://www.nrcc.cornell.edu). Used with permission.

NOTE: In this table, "avg. temp" is the temperature average from the indicated month, while the "normal temp" is the 30-year average (from 1991-2020) for that month's temperatures.

Precipitation

Figure 5 shows how the total precipitation for September 1 through November 30, 2024, differed from normal, with normal being defined as the average fall precipitation from 1991–2020. Only portions of southern and western Virginia and southeastern West Virginia experienced above normal precipitation. The amount of precipitation compared to normal generally decreased from west to east across the region, with much of Delaware and eastern Maryland and eastern Pennsylvania experiencing less than 25 percent of normal precipitation. The areas that received more precipitation than normal over the course of the season were those impacted by the tropical system discussed in Part 1 above.

Figure 5. September 1 – November 30, 2024, Percentage of Normal Precipitation

A heat map showing departure from normal precipitation for the Mid-Atlantic region for September to November, 2024. Source: Northeast Regional Climate Center, 2023

SOURCE: Northeast Regional Climate Center, 2024 (http://www.nrcc.cornell.edu). Used with permission.

NOTE: Normal seasonal precipitation is based on precipitation data from 1991–2020. Brown shades indicate below normal seasonal precipitation. Blue shades indicate above normal seasonal precipitation. The boundaries of the Chesapeake Bay watershed are outlined in bold black. Average departures from normal precipitation are based on a station's normal precipitation for fall compared with the same station's fall 2024 average amount of precipitation. Station-level departures from normal are spatially interpolated across the region. Both are produced by the Northeast Regional Climate Center. These can be found at https://www.rcc-acis.org/docs_gridded.html.

Fall 2024 ranked among the top 20 driest fall seasons on record for seven sites in the watershed (Table 3). Notably, it was Salisbury, Maryland's driest fall on record.

Table 3. Fall Season (September–November) Precipitation Rankings (driest)

Station Name Precipitation (inches) Normal Precipitation (inches) Rank (driest)
Salisbury, MD 3.00 11.79 1
Martinsburg, WV 3.23 9.75 3
Dulles Airport, VA 5.25 10.72 5
Williamsport, PA 4.71 11.71 5
Baltimore, MD 4.84 11.51 11
Binghamton, NY 7.43 10.88 16
Scranton, PA 6.16 10.71 18
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (driest)

SOURCE: Northeast Regional Climate Center, 2024 (https://www.nrcc.cornell.edu). Used with permission.

Monthly Precipitation Rankings

September 2024 ranked among the 20 driest Septembers on record for several sites, but was the ninth wettest September for Charlottesville, Virginia.

Salisbury, Maryland only saw 0.01 inches of precipitation in October, making it not only the site's driest October on record, but also the site's all-time driest month on record.99 October 2024 ranked among the 10 driest Octobers on record for many other sites across the watershed (Table 4).

Several sites experienced their longest streak of consecutive days without measurable precipitation (defined as at least 0.01 inches). This included Baltimore, Maryland and Dulles Airport, Virginia, which did not see measurable precipitation for 38 straight days (October 3-November 9). Meanwhile, record-long streaks were also set at Salisbury, Maryland (39 days from October 2 – November 9), Norfolk, Virginia (36 days from October 3-November 7), and Martinsburg, West Virginia (33 days from October 8-November 9). For several other sites, it was among the 10 longest such stretches.100

The full set of monthly rankings, locations, and amounts of precipitation are shown in Table 4.

Table 4. Monthly Precipitation Rankings

September Precipitation Rankings (driest)
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (driest)
Scranton, PA 1.04 4.15 9
Williamsport, PA 1.11 4.76 11
Salisbury, MD 1.29 4.48 14
Binghamton, NY 2.06 4.01 18
September Precipitation Rankings (wettest)
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (wettest)
Charlottesville, VA 9.35 4.09 9
October Precipitation Rankings (driest)
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (driest)
Salisbury, MD 0.01 4.15 1
Dulles Airport, VA 0.13 3.65 3
Lynchburg, VA 0.20 3.12 3
Norfolk, VA 0.06 3.86 3
Martinsburg, WV 0.42 2.99 4
Scranton, PA 0.71 3.71 4
Harrisburg, PA 0.47 3.81 5
Charlottesville, VA 0.37 3.31 6
Baltimore, MD 0.36 3.94 8
Binghamton, NY 1.35 3.76 10
Richmond, VA 0.61 3.39 10
Williamsport, PA 1.06 3.70 10
November Precipitation Rankings (driest)
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (driest)
Martinsburg, WV 0.80 2.73 13
Dulles Airport, VA 1.85 3.13 17
November Precipitation Rankings (wettest)
Station Name Precipitation (inches) Normal Precipitation (inches) Rank (wettest)
Scranton, PA 4.41 2.85 17
Binghamton, NY 4.02 3.11 19

Source: Northeast Regional Climate Center, 2024 (https://www.nrcc.cornell.edu). Used with permission.

Part 3: Winter 2024–2025 Outlook

Temperature and Precipitation

As of November 21, 2024 the NOAA Climate Prediction Center forecasts a 40-50-percent chance of above normal temperatures for most of the Mid-Atlantic region for the winter 2024–2025 season.101 Northwest Pennsylvania and western New York are forecasted to have a 33-40-percent chance of above normal temperatures.102 The precipitation forecast shows an equal chance of wetter than, drier than, or near-normal conditions for most the region for the same period. The very southeastern portion of Virginia has a 33-40-percent chance of below normal precipitation, while northwestern Pennsylvania has a 33-40-percent chance of above normal precipitation for December, January, and February.103

Drought Incidence

The U.S. Seasonal Drought Outlook identifies how drought might change across the United States and categorizes areas by whether drought could develop or become more or less intense. As of November 30, 2024, the Outlook indicates that drought conditions will persist in portions of West Virginia, central and northern Virginia, nearly all of Maryland, all of Washington, D.C., all of Delaware, and the eastern half of Pennsylvania.104 The Outlook predicts that there will be no drought in central and western Pennsylvania, much of upstate New York, and southern Virginia through February 28, 2025.105 Drought conditions are expected to improve in northern West Virginia, southwestern Pennsylvania, and the westernmost piece of Maryland.106

Climate Circulation Patterns

NOAA's Climate Prediction Center, which monitors the likelihood of occurrence of El Niño and La Niña climate phenomena, has a La Niña watch active as of November 14, 2024.107 La Niña conditions are expected to develop during the fall season or in early winter (57 percent chance in October – December) and will likely continue through the winter season.108 La Niña generally indicates that there will be average to slightly above average temperatures and below normal precipitation and snowfall in the winter season in the Baltimore-Washington area.109 However, a weak La Niña is expected this winter, which means it may have less of an impact on winter weather.110

ENSO conditions are one of the factors taken into account in NOAA's long-term forecasts and seasonal outlooks such as the one included in this climate summary.111 However, other regional climate dynamics and natural climate variability also influence weather in the Mid-Atlantic. Additional information on La Niña and El Niño is available from the Pacific Marine Environmental Laboratory (La Niña, El Niño).

Part 4: Comparison of Updated Climate Projections for Extreme Temperature and Precipitation

The past two climate summaries have presented updated climate projections for extreme temperature and extreme precipitation. These projections are based on the Coupled Model Intercomparison Project 6 (CMIP6) suite of models that have been downscaled to a finer spatial resolution using the Localized Constructed Analogs 2 (LOCA2) methodology.112 Previous data tools utilized the CMIP5 suite of models downscaled based on the original LOCA methodology. Understanding how these two datasets differ can be helpful for localities and utilities seeking to update their climate data from to the CMIP6 LOCA2 datasets. The CMIP5 and CMIP6 datasets differ in a number of important ways, including their use of future climate scenarios, model sensitivities to greenhouse gas emissions, and downscaling methodologies. Prior climate summaries have described the differences between the CMIP5 LOCA and CMIP6 LOCA2 datasets in greater detail (see Part 4). The following data tools provide a side-by-side comparison of CMIP5 to CMIP6 LOCA downscaled climate data.

Key Findings

  • Precipitation: CMIP6 models generally project wetter conditions compared to CMIP5 models. For example, CMIP6 models project that parts of Western Pennsylvania and Western Virginia will potentially see twice as many extreme precipitation days as was projected by the previous CMIP5 models.
  • Temperature: Minimal differences between CMIP5 and CMIP6 projections across the region are within the range of uncertainty expected from an update.

Guidance for Practitioners

  • Temperature: CMIP5 projections are likely sufficient and within the range of uncertainty in CMIP6 for the majority of the region but comparing datasets using the tool below could identify any cases in which the datasets differ by more than a few days.
  • Precipitation: While uncertainty in precipitation is much greater than temperature, CMIP5 may underestimate extreme precipitation in much of the region. Practitioners should compare CMIP6 projections to assess differences, implications for cost and risk, and the need for adopting updated projections.

Figure 6. CMIP5 vs. CMIP 6 Extreme Temperature Projections

How to Use the Tool

Selecting Temperature Thresholds and Time Periods: Use the filters to the right of the maps to adjust the temperature threshold, future time period, and climate scenario.

Technical Notes

Localized Constructed Analogs 2 (LOCA2) is a downscaled climate data product available at 6 km resolution over the continental United States.113 The LOCA2 dataset includes 27 of the climate models available in the Coupled Model Intercomparison Project 6 (CMIP6) archive, for three future climate scenarios: an intermediate-emissions future (Shared Socioeconomic Pathway (SSP) 2-4.5), a high-emissions future (SSP 3-7.0) and a very high-emissions future (SSP 5-8.5).114 For this tool, we used LOCA2 data over the Mid-Atlantic region from 2021-2100 (or 2099 for some models). Access LOCA2 datasets and learn more about the methodology.

Figure 7. CMIP5 vs. CMIP 6 Extreme Precipitation Projections

How to Use the Tool

Selecting Temperature Thresholds and Time Periods: Use the filters to the right of the maps to adjust the precipitation threshold, future time period, and climate scenario.

Technical Notes

Localized Constructed Analogs 2 (LOCA2) is a downscaled climate data product available at 6 km resolution over the continental United States.115 The LOCA2 dataset includes 27 of the climate models available in the Coupled Model Intercomparison Project 6 (CMIP6) archive, for three future climate scenarios: an intermediate-emissions future (Shared Socioeconomic Pathway (SSP) 2-4.5), a high-emissions future (SSP 3-7.0) and a very high-emissions future (SSP 5-8.5).116 For this tool, we used LOCA2 data over the Mid-Atlantic region from 2021-2100 (or 2099 for some models). Access LOCA2 datasets and learn more about the methodology.

Back to top

The Mid-Atlantic Regional Integrated Sciences and Assessments (MARISA) Seasonal Climate Impacts Summary and Outlook is a quarterly series produced by the MARISA program, a collaboration funded by NOAA through the RAND Corporation and researchers at Pennsylvania State University, Johns Hopkins University, Cornell University, the Virginia Institute of Marine Science, Morgan State University, and Carnegie Mellon University. This series is specifically designed to support policymakers, practitioners, residents, and community leaders in the Mid-Atlantic by serving as a data and information resource that is tailored to the region. It draws information from regional climate centers, news and weather information, and regional-specific climate data sets. Projections of weather and climate variability and change in the Mid-Atlantic region come from the best available scientific information. For any questions or comments, please contact Krista Romita Grocholski at Krista_Romita_Grocholski@rand.org.

This edition of the MARISA Seasonal Climate Impacts Summary and Outlook was authored by Krista Romita Grocholski (RAND Corporation), Michelle E. Miro (RAND Corporation), Jessica Spaccio (Cornell University), Samantha Borisoff (Cornell University), Lena Easton-Calabria (RAND Corporation), and Arthur T. DeGaetano (Cornell University).

Citation: Romita Grocholski, Krista, Michelle E. Miro, Jessica Spaccio, Samantha Borisoff, Lena Easton-Calabria, and Arthur T. DeGaetano, Mid-Atlantic Regional Climate Impacts Summary and Outlook: Fall 2024. Santa Monica, CA: RAND Corporation, 2024.

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Footnotes

  1. https://www.weather.gov/bgm/pastWinterNovember222024 Return to text ⤴

  2. https://www.weather.gov/bgm/pastWinterNovember222024 Return to text ⤴

  3. https://x.com/NWSStateCollege/status/1860372006740590699/photo/1 Return to text ⤴

  4. https://x.com/NWSStateCollege/status/1860372006740590699/photo/1 Return to text ⤴

  5. http://climod2.nrcc.cornell.edu/ Return to text ⤴

  6. https://droughtmonitor.unl.edu/data/png/20240903/20240903_huc02_cat.png Return to text ⤴

  7. https://droughtmonitor.unl.edu/data/png/20240903/20240903_huc02_cat.png Return to text ⤴

  8. https://droughtmonitor.unl.edu/data/png/20240917/20240917_huc02_cat.png Return to text ⤴

  9. https://droughtmonitor.unl.edu/data/png/20241001/20241001_huc02_cat.png Return to text ⤴

  10. https://www.potomacriver.org/news/icprb-in-drought-monitoring-status-as-of-september-11-2024/ Return to text ⤴

  11. https://agindrought.unl.edu/data/v2/extra-products/20240915/NASS%20Topsoil%20Moisture/Topsoil%20Moisture%20SVS%20Color.png Return to text ⤴

  12. https://www.nvdaily.com/nvdaily/slow-summer-on-the-river-has-ripple-effect-on-local-business/article_657072f7-6cab-5ef0-a94e-9ce292125e99.html Return to text ⤴

  13. https://www.potomacriver.org/news/news-from-around-the-basin-september-26-2024/ Return to text ⤴

  14. https://agindrought.unl.edu/data/v2/extra-products/20240929/NASS%20Topsoil%20Moisture/Topsoil%20Moisture%20SVS%20Color.png Return to text ⤴

  15. https://augustafreepress.com/news/drought-warning-downgraded-for-shenandoah-region-thanks-to-rain-from-helene/ Return to text ⤴

  16. https://news.maryland.gov/dnr/2024/09/19/maryland-fall-foliage-preview-2024/ Return to text ⤴

  17. https://droughtmonitor.unl.edu/data/png/20241001/20241001_huc02_cat.png Return to text ⤴

  18. https://droughtmonitor.unl.edu/data/png/20241029/20241029_huc02_cat.png Return to text ⤴

  19. https://droughtmonitor.unl.edu/data/png/20241029/20241029_huc02_cat.png Return to text ⤴

  20. https://droughtmonitor.unl.edu/data/png/20241029/20241029_huc02_cat.png Return to text ⤴

  21. https://droughtmonitor.unl.edu/data/png/20241029/20241029_huc02_cat.png Return to text ⤴

  22. https://www.weather.gov/media/phi/DGT/DGT_PHI_11012024.pdf Return to text ⤴

  23. https://www.wgal.com/article/dauphin-county-lykens-wiconisco-towship-mandatory-water-restriction/62754333 Return to text ⤴

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  30. https://www.lancasterfarming.com/farming-news/field-crops/dry-weather-defines-grain-harvest-across-mid-atlantic/article_d5eca662-8b30-11ef-b87f-6bec80eba340.html Return to text ⤴

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