We are now just past the halfway mark this year, so it seems like a good time to take a step back and observe what has occurred thus far. How did our January through June compare to climatology?
The first month of the year brought well above-normal temperatures to the contiguous United States, making it the fifth warmest in the 126-year record. This warmth kept surface water temperatures above freezing for the majority of the Great Lakes. In fact, Lake Erie, which averages just over 50 percent ice coverage at the end of January, was only 0.4 percent frozen on January 31.
On the other hand, our northernmost state had a drastically different experience than those of us in the lower 48. Alaska’s average January temperature was 8.4 degrees lower than the long-term average. This tied with 1970 as the 13th coldest January on record for the state and the coldest January since 2012. The cold January temperatures aided in the recovery of the Bering Sea Ice extent during January, which increased to 81 percent of average for this time of year.
Precipitation patterns were less uniform across the United States, with below-average precipitation occurring across much of the Southwest, Florida, and portions of the High Plains and Northeast, while the Paific Northwest and portions of the central and southern United States observed much wetter than normal conditions.
January 10-12 also brought severe weather, flooding, and tornadoes to the South, Southeast, and Great Lakes regions, which ultimately became the first Weather and Climate Disaster event of the year.
Note: The National Centers for Environmental Information (NCEI) created a database of billion-dollar disasters (all weather and climate-related disasters exceeding 1 billion dollars; identified in this blog as a Weather and Climate Disaster) for the United States in 1980. This indicator provides insight into the frequency and the total estimated costs of major weather and climate events, and they have worked with economic experts to ensure consistency with the numbers, including adjustments for inflation using the Consumer Price Index (CPI), for each event.
Continued cold weather across Alaska made it the coldest February since 1999, helping to serve as a catalyst for rapid ice growth across the Bering Sea. This was the first February since 2013 that the Bering Sea ice extent was not below average. In the lower 48, much warmer than normal temperatures were observed across parts of the Mid-Atlantic and Northeast as well as portions of California and Florida, with New Jersey and Rhode Island both observing their third warmest February. While below-average temperatures were observed across portions of the central Rockies to western Texas during February, no state ranked below average for the month.
The warm temperatures helped keep the Great Lakes surface temperatres above freezing across a large portion of the basin, thereby extending the season of lake-effect snow events. This was certainly the case February 27-29, when heavy lake effect snowfall blew across the Tug Hill Plateau region of upstate New York. Carthage, New York received 48 inches of snowfall from the storm!
Much of the Southeast experienced much-above-average to record wet conditions during February, as flooding rainfall on multiple days caused landslides and severe damage to roads and other infrastructure. In Jackson, Mississippi, the Pearl River crested at its highest level since 1983, inundating many homes. Several other rivers across Alabama and Mississippi were near-to or above flood stage. Georgia ranked second wettest, while Alabama and North Carolina ranked third wettest for the month. On the other end of the spectrum, many locations in California reported less than 5% of average rainfall, leading to California experiencing the driest February on record.
Severe weather impacted many South, East and Northeastern states (including AL, FL, GA, SC, LA, MS, TN, NC, VA, PA, RI, NY, NJ, MD and MA) February 5 into February 7. Over 20 tornadoes and hundreds of high wind damage reports contributed to the second Weather and Climate Disaster of the Year.
March brought above-average temperatures from the Rocky Mountains to the East coast, and record warm was observed across much of the Gulf Coast (Florida recorded its warmest March on record!). Western US mostly saw near average temperatures, with California ranking cooler than average. For the first time in the year, Alaska’s temperature was above the long-term average. The warmer temperatures, combined with southerly winds pushing the Bering Sea ice into warmer waters contributed to a startling 77,000 square miles of ice melt!
Overnight tornadoes across Tennessee on March 2-3 caused more than 40 buildings collapse and left a trail of destruction across northern Nashville and surrounding communities. The third Weather and Climate Disaster of 2020 caused more than two dozen fatalities. Additionally, tornado warnings were issued for Kauai and Niihau islands on March 17, the first for any of the Hawaiian islands since 2008! Severe weather March 27 and March 28 caused damage across many Midwest and Ohio Valley states including Missouri, Oklahoma, Texas, Illinois, Indiana, Ohio, Arkansas, Kentucky, Tennessee, West Virginia and Pennsylvania. High winds, hail, and two dozen tornadoes were reported.
April 2020 was marked by relatively normal temperatures and precipitation across the US. In fact it was the first slightly cooler than average month of the year. There were three Weather and Climate Disasters in April, beginning April 7 through April 8, when numerous hail storms, tornadoes, and high wind events caused damage across many North Central and Ohio Valley states. The most notable event of April (and the sixth Weather and Climate Disaster of the year) occurred mid-month, when an outbreak of at least 140 tornadoes stretched from Texas to Maryland – the deadliest outbreak since 2014. With more than a million homes and businesses losing power, 35 fatalities, and $3.0 B in estimated cost, this was the worst (in terms of lives lost and cost) Weather and Climate Disaster event recorded thus far in 2020. April 21 through April 23 brought the seventh Weather and Climate Disaster of the year, with high winds, hail, and tornadoes causing damage across many Southern states.
Utqiaġvik (Barrow), Alaska, had a record-low temperature of -20 degrees F on April 29. This was the first record low in more than 12 years and the latest in the season where a temperature of -20 degrees or colder has occurred.
A ridge of high pressure over Alaska and the West Coast and a trough over the East Coast were the primary drivers for warmer than normal temperatures across the west and cooler than normal temperatures that stretched from the Plains to the eastern portions of the country. A southward dip in the jet stream across the eastern U.S. during early May contributed to late-season snowfall. Pockets of 6 to 12 inches of snow fell from Vermont to Maine on May 8-9 and were accompanied by record-cold low temperatures across much of the East.
Above average precipitation was observed across the Northwest and from parts of the western Gulf Coast into the Great Lakes and Carolinas, while below average precipitation was recorded across portions of the Southwest, Rockies, and parts of the Northeast and South. Deep tropical moisture brought heavy rainfall and flooding across parts of the Midwest and Southeast during May. Chicago received 9.51 inches of precipitation during May — 250 percent of average for the month and the wettest May on record for the Windy City! Catastrophic failures at the Edenville and Sanford dams lead to flash flooding along the entire Tittabawassee River near Midland, Michigan, on May 19 following heavy rainfall received over the previous week. Approximately 10,000 residents had to be evacuated.
Tropical Storm Bertha moved across southern Florida May 25-May 26, causing Miami and its suburbs to flood, with widespread rainfall totals of 4-8 inches reported. Miami reported 7.40 inches of rain on May 26 — the third largest 1-day May total for the city and the 10th largest 1-day total observed for any month on record.
May had the fewest number of severe weather reports since May 2014 as well as the fewest number of tornadoes and EF2+ tornadoes reported since at least 1970. However, there were three Weather and Climate disasters in May. The first occurred across several Central and Eastern states May 3 into May 5, where high wind and hail damage were the predominant factors. A combination of high winds, hail, and tornadoes affected numerous Southern, Central, and Eastern states May 20 through May 23, resulting in the ninth Weather and Climate Event of the year. The tenth event of the year occurred in South Texas, where hail storms caused widespread impact to several cities with golf-ball sized hail damaging many homes, vehicles and businesses on May 27.
June brought warmer and drier than normal conditions to the contiguous United States as a whole, with above-average temperatures observed across New England into the Great Lakes and northern Plains into the Southwest, along with portions of the West and Gulf coasts. Below-average June temperatures were scattered across portions of the Deep South, Southeast and northern Rockies.
Sea ice melt in the Chukchi Sea (see above picture for reference) was slower than average for this time of year, and the June sea ice extent was 92% of average. Alaska received 3.24 inches of precipitation during June, which is 0.90 inch above average and ranked seventh wettest on record. Both Juneau and Ketchikan in the Panhandle had their wettest June on record. Above-average precipitation was observed across portions of the Pacific Northwest, northern and central Rockies, Great Lakes, Deep South and the Mid-Atlantic regions. Below-average precipitation occurred across portions of the Southwest, Great Plains, Ohio Valley, Southeast and much of the Northeast.
Year to Date (January – June 2020)
Above-average to record-warm January-June temperatures were observed across the vast majority of the Lower 48 states. Florida ranked warmest on record for this six-month period while New Jersey ranked third warmest and Rhode Island and Massachusetts ranked fourth warmest. The Alaska statewide average temperature for the year-to-date period was 21.4°F, 0.1°F below average.
Above-average precipitation occurred across portions of the Northwest and Southwest and from Texas to the Great Lakes and into the Southeast. Tennessee ranked wettest on record, North Carolina ranked fourth wettest and West Virginia and Alabama ranked fifth wettest for this year-to-date period. Below-average precipitation was observed from the West Coast into parts of the central and southern Rockies and from the southern High Plains to the Northern Tier. Below-average conditions were also present across the Northeast and parts of Florida.
This has been a record sixth consecutive year with at least 10 separate billion-dollar disasters and is at near-record pace for billion-dollar disasters during the first half of the year — 2020 is tied with 2011 and 2016, but trailing 2017 by one event. All 10 events were due to severe storms, which occurred across more than 30 states from the Great Lakes to the Gulf Coast. In addition to significant economic impacts, these events resulted in 80 fatalities.