KENTUCKY MONTHLY AND ANNUAL CLIMATE SUMMARY FOR -- 2021 By: Matt Dixon -- UK Agricultural Weather Center * Data tables courtesy of the Midwestern Regional Climate Center cli-MATE toolkit, available at: https://mrcc.purdue.edu/CLIMATE/ === Kentucky Climate Summary For the Period December 2021 Well Above Normal Temperatures and Near Normal Precipitation: December 2021 was the second warmest December on record with data going back to 1895. The warmth was steadfast throughout the month, consisting of very few days with below normal temperatures in place. Many even saw record breaking temperatures on Christmas Day with highs jumping into the low to middle 70s. Normal highs for this time of year are in the low to middle 40s. Precipitation ran close to normal with a little over 4 inches on average across the state. Overall, the state averaged 53.40 inches for the year, which is about three inches above normal and a fourth straight year of above normal rainfall. Unfortunately, the month will always be remembered for one of the worst tornado outbreaks in Kentucky history. On December 10/11th, 66 tornadoes touched down across 8 states. Kentucky was one of the hardest hit with multiple long-track tornadoes. The strongest was across Western Kentucky, which went through the towns of Mayfield, Princeton, and Dawson Springs. Rated as an EF4 tornado, estimated peak winds were 190 mph and resulted in catastrophic damage to the region. This tornado was on the ground for roughly 165 miles in Kentucky, from Fulton to Breckinridge Counties. Maximum width was estimated at 1.13 miles. Looking at the NCEI Storm Events Database, this was the first EF4+ tornado to ever occur during the month of December in Kentucky. More information on the event and specific tornadoes can be found on the National Weather Service webpages below. Paducah NWS - https://www.weather.gov/pah/December-10th-11th-2021-Tornado Louisville NWS - https://www.weather.gov/lmk/December112021Tornadoes STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 48.6 37.9 10.7 5.04 4.57 0.46 110 CENTRAL(CD2) 49.4 37.8 11.6 5.20 4.83 0.37 108 BLUEGRASS(CD3) 46.6 36.4 10.2 4.34 3.98 0.36 109 EAST(CD4) 46.2 37.0 9.2 3.28 3.87 -0.58 85 -------------------------------------------------------------------------------- STATE 47.6 37.3 10.3 4.37 4.28 0.09 102 === Kentucky Climate Summary For the Period November 2021 Below Normal Temperatures and Precipitation: November 2021 ran on the cool side with below normal temperatures in place. The growing season officially came to an end over the first week of the month with multiple nights well below the freezing mark. In fact, many dipped into the mid to upper 20s. Following a couple weeks of up and down temperatures, November closed with yet another bout of well below normal temperatures. Lows even dipped into the middle teens to low 20s on the morning of the 23rd. Precipitation-wise, the state saw much below normal precipitation. Kentucky only averaged about two inches for the month, which is roughly 1.5 inches below normal. This was the first month since May that Kentucky had seen drier than normal conditions. November 2021 was also the driest month recorded in Kentucky since the drought in September of 2019. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 43.7 47.8 -4.1 2.03 4.52 -2.49 45 CENTRAL(CD2) 44.0 47.1 -3.1 2.49 4.29 -1.80 58 BLUEGRASS(CD3) 42.7 45.9 -3.1 2.09 3.68 -1.59 57 EAST(CD4) 42.5 45.8 -3.3 1.70 3.73 -2.03 46 -------------------------------------------------------------------------------- STATE 43.2 46.6 -3.4 2.04 4.04 -2.00 51 === Kentucky Climate Summary For the Period October 2021 Above Normal Temperatures and Precipitation: Fall is normally the driest time of the year for the Bluegrass State, but Mother Nature had different plans in October 2021. The state saw a fifth straight month of above normal rainfall as the state averaged over four inches. Harvest progress was hindered at times with slow moving disturbances, but the state also saw plenty of dry windows throughout the month. Looking at temperatures, Kentucky saw the 8th warmest October ever recorded (data back to 1895). Highs in the 80 were frequent across the early and middle stages of October, which is about 10 to 15 degrees above normal for this time of year. Saying that, cooler temperatures did arrive towards the end of October behind a strong cold front. While just patchy in nature, some saw the first frost of the fall season on the morning of the 27th. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 63.4 58.7 4.8 3.96 3.17 0.79 125 CENTRAL(CD2) 63.5 57.5 6.0 4.75 3.20 1.54 148 BLUEGRASS(CD3) 61.7 56.3 5.4 4.61 2.93 1.68 157 EAST(CD4) 60.9 55.8 5.1 3.66 2.93 0.73 125 -------------------------------------------------------------------------------- STATE 62.3 57.0 5.3 4.18 3.05 1.13 137 === Kentucky Climate Summary For the Period September 2021 Above Normal Temperatures and Precipitation: The wet trend throughout summer 2021 continued into September with yet another month of above normal rainfall. The state averaged over 4 inches with the brunt falling over the latter half of the month. The most prominent event occurred between the 20th and 22nd when the state averaged 1.67 inches. Temperatures were up and down throughout September. In one example, highs rose into the 80s on a near daily basis between the 13th and 19th, but the next week, much of Kentucky saw lows in the low to middle 40s behind a strong cold front. Ultimately though, the temperature swings evened out as the average temperature for the month was near normal. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 70.4 70.0 0.4 3.66 3.37 0.28 108 CENTRAL(CD2) 69.7 68.8 0.9 5.63 3.90 1.73 144 BLUEGRASS(CD3) 68.9 67.8 1.1 4.85 3.26 1.59 149 EAST(CD4) 67.7 67.3 0.4 3.25 3.41 -0.16 95 -------------------------------------------------------------------------------- STATE 69.1 68.4 0.7 4.23 3.48 0.75 121 === Kentucky Climate Summary For the Period August 2021 Above Normal Temperatures and Precipitation: August 2021 marked a third straight month of above normal rainfall for the Bluegrass State. Outside of a dry start to August, the rest of the month generally followed an active pattern with numerous rounds of showers and storms. In fact, the state averaged over 1.5 inches for two straight weeks. A combination of slow storm movement and excessive rainfall led to some localized flooding. Some locations across the Southern Bluegrass and Eastern KY even saw in excess of 5 inches between the 16th and 22nd, alone. August closed with a cold front and the remnants of Hurricane Ida passing through the area, leading to accumulations of 1-3+ inches across much of the state. Overall, the state averaged over 5 inches for the month. Looking at temperatures, August 2021 ranks as the 25th warmest August on record for the state (data back to 1895). Outside of a cooler start to the month, above normal temperatures were fairly consistent, including a couple bouts of extreme heat. One of the more intense heat events occurred between the 10th and 13th when highs consistently jumped into the upper 80s to middle 90s. Combined with an extremely humid airmass, heat indices peaked in the 100-to-110-degree range. This pushed the livestock heat stress index into the danger and emergency categories across the state. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 78.0 76.8 1.1 4.09 3.19 0.90 128 CENTRAL(CD2) 77.7 75.4 2.3 5.40 3.52 1.88 153 BLUEGRASS(CD3) 76.5 74.5 2.0 5.10 3.72 1.38 137 EAST(CD4) 75.3 73.7 1.6 6.88 3.91 2.98 176 -------------------------------------------------------------------------------- STATE 76.7 75.0 1.7 5.49 3.60 1.88 152 === Kentucky Climate Summary For the Period July 2021 Below Normal Temperatures and Above Normal Precipitation: The first and second halves of July were nearly total opposites. The month started with a very active pattern in place. In fact, the state averaged over an inch for three weeks in a row dating back into the latter stages of June. Heavy rain led to localized bouts of flooding. One of the more prominent events occurred on the first of the month when Southern Fayette and Clark Counties saw 4-6 inches. Conditions then took a turn in the opposite direction and turned dry for most of the state through the remaining couple weeks of the month. One exception was across Eastern Kentucky on the 30th when a large area saw more than two inches, resulting in some more localized flooding. While turning dry, the state still averaged 6.06 inches for the month, which is over an inch above normal. Temperatures ran close to seasonable norms for the first half of July with typical summer-time humidity. As conditions dried out later in the month, temperatures started taking a step higher with heat indices topping the century mark from time to time. Some of the warmest temperatures of the summer season were felt between the 27th and 29th as highs jumped into the upper 80s to middle 90s. Combined with high humidity, livestock heat stress rose into the danger and emergency categories during the afternoon and evening hours. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 77.9 78.5 -0.6 5.48 4.36 1.12 126 CENTRAL(CD2) 76.6 76.9 -0.3 5.52 4.76 0.76 116 BLUEGRASS(CD3) 74.8 75.7 -0.9 6.52 4.96 1.56 131 EAST(CD4) 74.5 75.0 -0.5 6.59 5.25 1.34 125 -------------------------------------------------------------------------------- STATE 75.9 76.4 -0.5 6.06 4.86 1.20 125 === Kentucky Climate Summary For the Period June 2021 Above Normal Temperatures and Precipitation: Following what was a dry month of May, a more active weather pattern returned to the area in June. Overall, the state averaged 4.83 inches for the month, which was slightly above normal. The more significant accumulations fell over the first couple weeks of June with the state averaging over three inches. At times, slow storms motions combined with a very moist air mass to produce localized bouts of flooding. The state then saw some solid dry windows over the second half of the month, giving producers a chance to get hay harvested, crops sprayed, or beans planted. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 75.6 75.2 0.4 3.72 4.49 -0.77 83 CENTRAL(CD2) 74.5 73.5 1.0 4.76 4.79 -0.03 99 BLUEGRASS(CD3) 72.9 72.2 0.7 5.86 4.83 1.03 121 EAST(CD4) 71.7 71.5 0.2 5.04 4.78 0.26 105 -------------------------------------------------------------------------------- STATE 73.5 73.0 0.5 4.83 4.72 0.11 102 === Kentucky Climate Summary For the Period May 2021 Below Normal Temperatures and Precipitation: Kentucky saw a second straight month of below normal rainfall. This marked the first time since 2018 that the two opening months of the growing season were drier than normal. Overall, the state only averaged 3.58 inches, which is about 1.5 inches below normal. Most of that 3.58 averaged fell over the first week of May. One of the more significant events was on the 3rd and 4th when some across South Central Kentucky saw 2-5+ inches in less than 6 hours, leading to numerous reports of flash flooding. Two straight weeks of dry conditions followed thereafter, presenting a fantastic opportunity for harvesting the first cut of hay for the year or putting grain crops in the ground. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 64.4 67.1 -2.7 3.67 5.12 -1.45 72 CENTRAL(CD2) 63.0 65.7 -2.7 4.63 5.27 -0.64 88 BLUEGRASS(CD3) 61.5 64.3 -2.8 3.56 5.18 -1.62 69 EAST(CD4) 61.2 63.9 -2.7 2.79 4.87 -2.08 57 -------------------------------------------------------------------------------- STATE 62.4 65.2 -2.8 3.58 5.09 -1.51 70 === Kentucky Climate Summary For the Period April 2021 Below Normal Temperatures and Precipitation: A warm month of March was followed by a very chilly start to April. Temperatures dropped below freezing for three straight nights behind a strong cold front. The coolest air was felt on the morning of April 2nd with lows in the low to middle 20s for much of the eastern half of Kentucky. The state then saw a quick warming trend thereafter with temperatures peaking in the 70s and even 80s at times over the next couple weeks. Below normal rainfall let farmers make headway in spring corn planting. In fact, through April 18th, data at the Ag Weather Center showed the state had only averaged 0.96 inches for the month, which was about 1.5 inches below normal. Kentucky then received another taste of winter over the third week of April. Widespread rain showers accompanied the boundary, but as temperatures plummeted, precipitation type turned to snow. Much of the state saw some minor accumulations on grassy and elevated surfaces, peaking across North Central Kentucky and the Bluegrass Region in the 1 to 2 inch range. Overall, the state only averaged about 3 inches for the month, which is nearly 2 inches below what is typically seen in April. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 56.5 58.0 -1.5 3.51 5.01 -1.50 70 CENTRAL(CD2) 55.0 56.8 -1.8 3.01 4.91 -1.90 61 BLUEGRASS(CD3) 53.0 55.2 -2.2 3.07 4.63 -1.56 66 EAST(CD4) 53.3 55.6 -2.3 2.49 4.45 -1.96 56 -------------------------------------------------------------------------------- STATE 54.4 56.4 -2.0 2.98 4.73 -1.75 63 === Kentucky Climate Summary For the Period March 2021 Above Normal Temperatures and Precipitation: In a complete flip of the pattern from February, temperatures ran above normal for much of the month of March. In fact, the state average temperature ran above normal for three straight weeks. The state saw several days with highs peaking in the 70s and even some low 80s on the 24th. Precipitation also ran above normal for the month as the state averaged 6.83 inches, marking a third straight month of above normal precipitation. The wet pattern did not really start until midway through the second week of the month. In fact, following a very significant round of rainfall to end February, most of Kentucky went 10 straight days without any rainfall to begin March. The state did see some severe weather, mainly on the 25th, with some isolated instances of large hail, damaging winds, and even a few weak tornadoes. Outside of severe weather, heavy rainfall did lead to multiple bouts of flooding, most notably over the weekend of the 27th and 28th when portions of SE Kentucky saw 2-3+ inches. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 52.5 48.1 4.4 6.87 4.78 2.09 144 CENTRAL(CD2) 51.0 46.9 4.1 7.59 4.88 2.72 156 BLUEGRASS(CD3) 48.6 44.9 3.7 5.36 4.50 0.86 119 EAST(CD4) 49.5 45.8 3.7 7.23 4.59 2.64 157 -------------------------------------------------------------------------------- STATE 50.4 46.4 4.0 6.83 4.68 2.15 146 === Kentucky Climate Summary For the Period February 2021 Well Below Normal Temperatures and Above Normal Precipitation: Dating back to 2016, February’s have been running warmer than normal for the Bluegrass State. Outside of February 2017, precipitation has also ran above normal, with more in the way of rainfall. That trend was broken in 2021 with the passage of several impactful winter storms through the area and well below normal temperatures. The focus for wintry weather surrounded three storms that hit the Bluegrass State in less than a week. The first came on February 10th and 11th in the form of a major ice storm. Accumulations ranged from a tenth to half inch+ for much of Kentucky. The ice resulted in hazardous driving conditions, tree damage and power outages, especially across Eastern Kentucky. The next round arrived on the 15th with a wintry mix across the state. Eastern Kentucky was hit with a second major ice storm in less than a week as another quarter to half inch+ fell across the area. At its peak, there was an estimated 150,000 customers without power across this region. Heavy sleet and snow mixed in with the ice farther to the north and west into Central KY (2-5+ inches), eventually transitioning to mostly snow (5-9 inches) across Western Kentucky. The winter weather then closed up with another event on the 17th and 18th, but luckily, snow was the main precipitation type with accumulations of 3 to 5 inches across the southern half of KY, tapering to the north. Very chilly air accompanied the latter two events with many locations dipping into the single digits and even below zero at times. For most, data has be traced back to winter 2015 to find the last time temperatures went below zero. Just like January, February then closed with significant rainfall across the region. The state averaged 2.81 inches over the last fews days of the month.Moderate to heavy rain led to bouts of extreme flooding, most notably across Eastern Kentucky. Overall, this pushed Kentucky to a second straight month of above normal precipitation. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 31.2 39.3 -8.1 3.41 4.02 -0.61 85 CENTRAL(CD2) 32.7 38.7 -6.0 4.83 4.10 0.73 118 BLUEGRASS(CD3) 30.7 36.5 -5.8 4.10 3.45 0.65 119 EAST(CD4) 33.7 38.2 -4.5 5.41 3.86 1.55 140 -------------------------------------------------------------------------------- STATE 32.2 38.2 -6.0 4.51 3.86 0.65 117 === Kentucky Climate Summary For the Period January 2021 Above Normal Temperatures and Precipitation: While the state saw some higher accumulations on New Year’s Day (most between 0.5 and 1.25 inches), all other precipitation events were fairly light in nature through the first three weeks of the month. Precipitation fell as a mix of snow and rain throughout with the former again limited to light accumulations. The dry weather led the US Drought Monitor to reintroduce an area of ‘abnormally dry conditions’ to much of South Central Kentucky. The tide then turned in a big way for the last week of January behind several rounds of widespread precipitation, some even in the form of snow. Overall, the state averaged 2.74 inches for the week in liquid equivalent. This was enough to push the Kentucky state average above normal for the month by just under a half inch. Temperatures ran slightly above normal for the month of January. Outside of some very warm temperatures on New Year’s Day in the middle 60s and low 70s, temperatures did not deviate too far from normal throughout the month. Kentucky largely avoided any major arctic air events with the coldest temperatures running in the teens for most of the state. STATION Temp Norm Dep Prcp Norm Dep %Norm -------------------------------------------------------------------------------- WEST(CD1) 37.0 35.3 1.7 4.57 3.72 0.85 123 CENTRAL(CD2) 36.2 34.9 1.3 4.64 3.89 0.75 119 BLUEGRASS(CD3) 34.2 32.9 1.3 4.06 3.48 0.58 117 EAST(CD4) 35.5 34.4 1.1 3.46 3.82 -0.36 91 -------------------------------------------------------------------------------- STATE 35.7 34.4 1.3 4.12 3.74 0.38 110 ===