Issued 13 December 2021

November 2021 Palmer Z-Index
U.S. Percent Area Wet or Dry January 1996 - November 2021
November 2021 /monitoring-content/sotc/drought/2021/11/wus-elem01-12112021.gif

Please note that the values presented in this report are based on preliminary data. They will change when the final data are processed, but will not be replaced on these pages

National Drought Highlights

Detailed Drought Overview

The upper-level circulation during November 2021 was very active with several shortwave troughs and closed lows moving through the jet stream flow. But they moved through a longwave pattern that consisted of a ridge over the western CONUS and a trough over the East. The shortwave troughs brought Pacific fronts with them, but the weather systems weakened as they moved through the anomalously strong western ridge. Surface lows were mostly directed along a track across the northern states. The western ridge kept moisture away from most of the West, and the resulting northwesterly flow in the jet stream over the central CONUS directed dry air masses into the central and eastern CONUS (maps of surface relative humidity [mean and anomaly], relative humidity aloft [mean and anomaly], and precipitable water [mean and anomaly]). The result was a drier-than-normal month across most of the country, with only parts of the Pacific Northwest, northern Minnesota, Deep South Texas, and Florida wetter than normal. The ridge west/trough east monthly circulation pattern resulted in a similar temperature anomaly pattern — a warmer-than-normal month in the West and a near to cooler-than-normal month across most of the East. Record-warm monthly temperatures occurred locally in the Southwest.

As a result of these conditions, drought or abnormal dryness expanded or intensified in the southern Plains to central High Plains, Lower to Mid-Mississippi Valley, Southeast to Mid-Atlantic Coast, Deep South Texas, and parts of the northern High Plains, as well as much of Hawaii and Puerto Rico. Beneficial precipitation caused drought or abnormal dryness to contract or decrease in intensity in parts of the Pacific Northwest and Upper Mississippi Valley, and a reassessment of conditions due to October precipitation resulted in contraction or reduction of intensity in other parts of the West and Midwest. Drought expansion exceeded contraction with the USDM-based national moderate-to-exceptional drought footprint across the CONUS rising from 47.8 percent at the end of October to 53.4 percent at the end of November (from 40.0 percent to 44.8 percent for the 50 States and Puerto Rico). According to the Palmer Drought Index, which goes back to the beginning of the 20th century, about 42.0 percent of the CONUS was in moderate to extreme drought at the end of November, an increase when compared to the end of October. The percent area of the CONUS in moderate to extreme drought has hovered between 35 and 49 percent for the last 15 months (since September 2020).

D0-D4D1-D4D2-D4D3-D4D4

Drought conditions at the end of November, as depicted on the November 30, 2021 USDM map, included the following core drought and abnormally dry areas:

Palmer Drought Index

The Palmer drought indices measure the balance between moisture demand (evapotranspiration driven by temperature) and moisture supply (precipitation). The Palmer Z Index depicts moisture conditions for the current month, while the Palmer Hydrological Drought Index (PHDI) and Palmer Drought Severity Index (PDSI) depict the current month's cumulative moisture conditions integrated over the last several months.

While both the PDSI and PHDI indices show long-term moisture conditions, the PDSI depicts meteorological drought while the PHDI depicts hydrological drought. The PDSI map may show less severe and extensive drought (as well as wet spell conditions) in some parts of the country than the PHDI map because the meteorological conditions that produce drought and wet spell conditions are not as long-lasting as the hydrological impacts.

November 2021 Palmer Z-Index
November 2021 Palmer Hydrological Drought Index

Used together, the Palmer Z Index and PHDI maps show that short-term drought occurred across the West (except parts of the Pacific Northwest), across most of the Plains to Mississippi Valley, across the Southeast (except Florida) and Mid-Atlantic states, and across the coastal Northeast and northern New England. In the West, western portions of the Great Plains, and Carolinas to Virginia, long-term drought continued, intensified, or expanded, while in the South, Southeast, and along the Mississippi Valley, long-term wet conditions contracted or decreased in intensity (PHDI maps for November compared to October). Short-term wet conditions in Coastal Washington and southern Florida contracted or decreased the intensity of long-term drought.

Standardized Precipitation Index

The Standardized Precipitation Index (SPI) measures moisture supply. The SPI maps here show the spatial extent of anomalously wet and dry areas at time scales ranging from 1 month to 24 months.

November 2021 Standardized Precipitation Index
October-November 2021 Standardized Precipitation Index
September-November 2021 Standardized Precipitation Index
June-November 2021 Standardized Precipitation Index

The SPI maps illustrate how moisture conditions have varied considerably through time and space over the last two years. Dryness covered most of the West, except the Pacific Northwest, at the 1-month time scale. The Pacific moisture and atmospheric river event of October gave parts of the West moist conditions at the 2- to 3-month time scales, except for the Southwest (4 Corners area) and Montana. Likewise, the October moisture and summer monsoon rains gave parts of the West wet conditions at 6 months, while other parts were dry. Northern and southwestern portions of the West were dry at 9 months, most of the West was dry at 12 months, and almost all of the West (except coastal Washington) was dry at 24 months. Much of the Great Plains and most of the country along and East of the Mississippi River were dry at the 1-month time scale. The western Great Lakes, Mid-Atlantic coast, and southern Plains to Lower Mississippi Valley were dry at the 2- and 3-month time scales. The central Plains, Upper Mississippi Valley, and parts of the Carolinas were dry at 6 months. Dryness is evident in the northern Plains, Upper Mississippi Valley, western Great Lakes, northern New England, and Carolinas at 9 to 12 months. At the 24-month time scale, dryness can be seen in the Upper Mississippi Valley, northern and western Great Plains, and northern New England. Wet conditions dominate the northern Plains, southern Great Lakes, and parts of the Northeast at 2 to 3 months, much of the Northeast and southern Great Lakes to Gulf of Mexico coast at 6 to 12 months, and from the Deep South to Atlantic coast and eastern Great Lakes at 24 months. An interesting pattern is evident at the 24-month time scale — very dry conditions dominate across the West to northern Plains, while very wet conditions dominate the Deep South to Atlantic Coast.

March-November 2021 Standardized Precipitation Index
December 2020-November 2021 Standardized Precipitation Index
December 2019-November 2021 Standardized Precipitation Index

Standardized Precipitation Evapotranspiration Index

The SPI measures water supply (precipitation), while the SPEI (Standardized Precipitation Evapotranspiration Index) measures the combination of water supply (precipitation) and water demand (evapotranspiration as computed from temperature). Warmer temperatures tend to increase evapotranspiration, which generally makes droughts more intense.

For the Northern Hemisphere, November marks the end of climatological autumn, which is the transition season from the warmest season of the year (summer, when evapotranspiration reaches its annual maximum) to the coldest season (winter, when evapotranspiration is minimal). During November 2021, temperatures were much above normal across most of the CONUS from the West Coast to the Mississippi River, with some local areas of record warmth in the Southwest. It was also very dry across most of the CONUS. The unusual warmth resulted in increased evapotranspiration in the West and much of the Plains. This led to a more severe SPEI than SPI across the West and Plains, especially in the Southwest. Much of the year was warmer than normal, especially beginning in June, with a large part of the West to northern Plains and parts of New England having the warmest June-November on record. Evapotranspiration was enhanced, especially where precipitation was below normal. This resulted in a more extreme SPEI than the SPI in these hot dry areas for most of the year (SPEI maps for last 1, 2, 3, 4, 5, 6, 9, 12 months) (SPI maps for last 1, 2, 3, 4, 5, 6, 9, 12 months), especially in the western half of the country.

California had the second driest November SPEI on record, exceeded only by November 1995. Montana had the second driest 6-month SPEI on record for November, exceeded only by June-November 1936. Oregon had the third driest 9-month SPEI on record for November, exceeded only by March-November 1936 and March-November 1939. The SPI was dry, but not nearly as dry, in each of these cases.

Rainfall from the summer monsoon and Pacific precipitation in October improved the precipitation ranks for the Western U.S., but November saw a return to very dry conditions. November 2021 was drier than normal regionwide for the West, but September-November 2021 and June-November 2021 still ranked on the wet side of average. The last 12 months ranked as the 12th driest such December-November 12-month period and December 2019-November 2021 ranked as the fourth driest such December-November 24-month period. Temperatures have been consistently warm, with regionwide rankings second warmest for November, sixth warmest for September-November, warmest on record for June-November, third warmest for the December-November 12-month period, and third warmest for the December-November 24-month period. The warmest December-November 12-month periods occurred in 2015 (warmest) and 1934 (second warmest). The warmest December-November 24-month periods occurred in 2016 (December 2014-November 2016, warmest) and 2015 (December 2013-November 2015, second warmest). Temperatures have been much warmer than normal in the Western U.S. for much of the last one to eight years, and have undergone a pronounced warming trend for the last 40 years.

The excessive warmth of the last several years has resulted in longer time scale SPEI values to be much drier than the corresponding SPI values (SPEI maps for last 18, 24, 36, 48, 60, 72 months) (SPI maps for last 18, 24, 36, 48, 60, 72 months). In spite of the beneficial precipitation from the 2021 summer monsoon and October weather systems, the SPEI was still record dry for longer time scales in several states:

  • Arizona (SPEI for last 18, 24, and 30 months) (SPI for last 18, 24, and 30 months)
  • California (SPEI for last 18 months) (SPI for last 18 months)
  • Nevada (SPEI for last 24 and 30 months) (SPI for last 24 and 30 months)
  • Utah (SPEI for last 24 months) (SPI for last 24 months).

Regional Discussion

Hawaii

November 2021 continued a drier-than-normal trend across Hawaii that has lasted for 8 months. A wet March resulted in a mixed anomaly pattern at the 9- to 12-month time scales, but the central islands (Oahu, Molokai, and Lanai) were mostly drier than normal, and this pattern was also evident at the 24- to 36-month time scales. Wetter-than-normal anomalies dominated at longer time periods (last 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 24, 36, 48, 60 months) (climate engine model percent of normal precipitation map for the last month). Monthly streamflow was below to much below normal across most of the state. Kauai was abnormally dry with some moderate drought. Areas of moderate to severe drought were on the rest of the main islands, with extreme to exceptional drought over Molokai and Maui. The overall drought footprint jumped from 38.5 percent of the state at the end of October to 56.8 percent on the November 30th USDM map.

Alaska

November 2021 was drier than normal across most of Alaska. Below-normal precipitation extended from western areas to the Northeast Gulf Coast at 2 to 3 months, then shifted to the Southwest to Cook Inlet-Bristol Bay area at 4 to 9 months and mainly Cook Inlet by 11 to 12 months. Cook Inlet was mostly dry at 24 months, but wetter-than-normal anomalies dominated the state at longer time scales (low elevation station precipitation anomaly maps for the last 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 24, 36, 48, 60 months) (high elevation SNOTEL station precipitation anomaly maps for the last 1 and 2 months) (SNOTEL basin precipitation anomaly map for the last 2 months) (climate division precipitation rank maps for the last 1, 3, 6, 11, and 12 months) (climate engine model percent of normal precipitation map for the last month) (Leaky Bucket model precipitation percentile map).

November was colder than normal across most of the state. Cooler-than-normal conditions dominated for the last 2-5 months. The western half of Alaska was colder than normal at the 6-month time scale, with near to cooler-than-normal conditions the rule at 11 months. At 12 months, warmer-than-normal anomalies were sneaking into the north coastal, Aleutian, and some panhandle regions (low elevation station temperature anomaly maps for the last 1, 2, 3, 4, 11, 12 months) (climate division temperature rank maps for the last 1, 3, 6, 11, 12 months) (Leaky Bucket model temperature percentile map). End-of-November satellite-based and SNOTEL (station, basin) observations of snow water equivalent (SWE) in snowpack were mostly near to above average with some below-average areas.

Monthly streamflow (for those streams that were not frozen) showed a mixed anomaly pattern with some below-normal streamflows in the Southwest, Aleutians, and panhandle. There was no drought or abnormal dryness on the November 30th USDM map.

Puerto Rico and U.S. Virgin Islands

November 2021 was much drier than normal across Puerto Rico (PR) and the U.S. Virgin Islands (USVI) with some locations having a wetter-than-normal month. Drier-than-normal conditions dominated the USVI and southern, eastern, and coastal areas of PR for the last 2 to 48 months. PR was mostly wetter than normal at the 60-month time scale (radar-based precipitation anomaly estimates for the last 1, 2, 3, 6, 11, 12 months) (low elevation station precipitation maps for the last 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 24, 36, 48, 60 months) (climate engine model percent of normal precipitation map for the last month: PR and USVI, Caribbean and Gulf of Mexico region).

Root zone analyses indicated that soil conditions were dry along the southern and northern coasts and eastern interior regions of PR with some dryness developing in interior regions (root zone soil saturation fraction; relative soil moisture at 0-10 cm [0-4 in], 10-40 cm [4-16 in], 40-100 cm [16-39 in], 100-200 cm [39-79 in] depth). Monthly streamflow in PR was mostly below to much below normal. In the USVI, groundwater continued to decline throughout November on St. Croix, St. Thomas, and St. John. On St. Thomas and St. John, groundwater levels were low but not at the record low values that occurred in 2016-17. On St. Croix, however, end-of-November 2021 levels were at the record low levels that occurred in 2016. Moderate drought ballooned from 1.8 percent of Puerto Rico at the end of October to 29.0 percent at the end of November. Conditions deteriorated in the USVI, with severe drought developing in the south on St. Croix, moderate drought developing on St. Thomas, and abnormal dryness returning to St. John.

CONUS State Precipitation Ranks

November 2021 was drier than normal across most of the CONUS. Forty states had a precipitation rank in the driest third of the 127-year historical record for November, including thirteen in the top ten driest category — Alabama and North Carolina (both fifth driest); Mississippi and West Virginia (both sixth driest); New Jersey (seventh driest); South Carolina and Tennessee (both eighth driest); Illinois, Maryland, Utah, and Virginia (each ninth driest); and Louisiana and Nevada (both tenth driest).

The last three months (September-November 2021) were drier than normal in Montana, the Southwest, central to southern Plains, Lower Mississippi Valley, western Great Lakes, and Mid-Atlantic coast. Ten states had a precipitation rank in the driest third of the 1895-2021 historical record for September-November, but none ranked in the top ten driest category. Wisconsin came close at eleventh driest.

June-November 2021 was drier than normal in parts of the Southwest, Pacific Northwest, Great Plains, Mississippi Valley, and Mid-Atlantic states. Five states had a precipitation rank in the driest third of the historical record, including Montana which ranked eighth driest.

January-November 2021 was drier than normal across much of the West and parts of the Great Plains, Upper Mississippi Valley, northern New England, southern Florida, and the Mid-Atlantic states. Twelve states had a precipitation rank in the driest third of the historical record, including Montana which ranked fourth driest.

December 2020-November 2021 was drier than normal in much the same areas as January-November. Twelve states had a precipitation rank in the driest third of the historical record, including (once again) Montana which ranked third driest. California and Idaho almost made the top ten driest category at 12th and 13th driest, respectively.

Agricultural Belts

During November 2021, the Primary Hard Red Winter Wheat agricultural belt generally was warmer and drier than average. The month ranked as the 22nd driest and eighth warmest November, regionwide, in the 1895-2021 record.

October marks the beginning of the growing season for the Primary Hard Red Winter Wheat belt. October-November 2021 was also warmer and drier than normal. The period ranked as the 56th driest and fifth warmest October-November, regionwide, on record.

As of November 30, drought affected approximately 85 percent of barley production, 72 percent of spring wheat production, 58 percent of the sheep inventory, 52 percent of winter wheat production, 51 percent of cotton production, 48 percent of the milk cow inventory, 44 percent of the cattle inventory, 41 percent of hay acreage, 38 percent of sorghum production, 31 percent of rice production, 19 percent of corn production, and 16 percent of soybean production.

November 28 USDA reports indicated that topsoil moisture was short or very short (dry or very dry) across 34 percent of the CONUS and subsoil moisture was short or very short across 38 percent of the CONUS. These values are more than a month ago. Twenty-three percent of the winter wheat crop was in poor to very poor condition. Those states having 30 percent or more of the topsoil or subsoil moisture short or very short, or 30 percent or more of the winter wheat crop in poor to very poor condition, at the end of November 2021 are listed in the table below.

November 2021 statewide table of percent of winter wheat crop in poor or very poor condition and percent of topsoil and subsoil moisture short or very short

U.S.-Affiliated Pacific Islands

The NOAA National Weather Service (NWS) offices, the Pacific ENSO Applications Climate Center (PEAC), and partners provided reports on conditions across the Pacific Islands.

In the U.S. Affiliated Pacific Islands (USAPI) (maps — Federated States of Micronesia [FSM], Northern Mariana Islands, Marshall Islands [RMI], Republic of Palau, American Samoa, basinwide), November 2021 was drier-than-normal in Palau and western and southern FSM. It was near to wetter than normal in other parts of the FSM and in American Samoa, the RMI, and the Marianas.

Monthly precipitation amounts were below the monthly minimum needed to meet most water needs (4 inches in the Marianas and Pago Pago, and 8 inches elsewhere) at Kapingamarangi, Fananu, and Yap (in the FSM), and at Airai (in Palau). November precipitation was above the monthly minimums at the rest of the stations across the USAPI. The 4- and 8-inch thresholds are important because, if monthly precipitation falls below the threshold, then water shortages or drought become a concern.

In the table below, the station identified as Koror is Palau International Airport (Airai).

Pacific Island Percent of 1981-2010 Normal Median Precipitation
Station Name Dec
2020
Jan
2021
Feb
2021
Mar
2021
Apr
2021
May
2021
Jun
2021
Jul
2021
Aug
2021
Sep
2021
Oct
2021
Nov
2021
Dec-
Nov
Chuuk182%114%156%223%55%244%60%135%48%143%138%112%124%
Guam NAS157%102%33%130%119%210%82%86%105%92%233%134%104%
Kapingamarangi38%65%63%78%150%129%72%99%52%40%30%29%67%
Koror142%102%166%119%287%178%56%73%101%164%233%70%120%
Kosrae185%188%141%194%106%154%194%166%67%107%129%122%124%
Kwajalein60%74%75%264%174%126%67%82%35%105%98%128%94%
Lukonor219%146%180%84%134%238%105%41%63%94%64%145%107%
Majuro147%150%57%228%135%285%84%84%91%111%119%130%130%
Pago Pago113%132%141%91%76%80%212%84%145%51%47%124%94%
Pohnpei168%147%65%216%77%152%141%93%66%105%95%174%123%
Saipan193%91%122%46%77%120%158%123%83%85%100%138%104%
Yap200%201%139%189%316%109%86%67%87%93%107%64%114%
Pacific Island Precipitation (Inches)
Station Name Dec
2020
Jan
2021
Feb
2021
Mar
2021
Apr
2021
May
2021
Jun
2021
Jul
2021
Aug
2021
Sep
2021
Oct
2021
Nov
2021
Dec-
Nov
Chuuk20.47"11.56"11.29"18.55"6.86"27.53"7.00"16.13"6.20"16.70"15.86"11.89"170.04"
Guam NAS8.02"4.11"1.01"2.70"3.02"7.14"5.08"8.76"15.44"11.61"26.68"9.87"103.44"
Kapingamarangi3.77"5.92"5.86"8.91"20.44"15.53"9.95"14.01"4.26"3.98"2.46"2.66"97.75"
Koror15.82"10.42"14.23"8.84"21.03"21.06"9.87"13.55"13.66"19.33"27.58"7.95"183.34"
Kosrae29.87"31.36"18.28"31.20"18.63"27.37"28.33"24.77"9.48"15.27"14.15"16.81"265.52"
Kwajalein4.02"2.34"1.97"6.21"9.17"8.45"4.61"8.05"3.43"11.30"10.97"14.47"84.99"
Lukonor24.71"12.29"16.11"7.81"15.21"27.86"12.26"6.61"8.83"9.50"7.25"13.20"161.64"
Majuro16.71"11.58"3.89"15.00"12.71"28.81"9.28"9.42"10.60"12.41"15.12"17.42"162.95"
Pago Pago14.55"17.62"16.86"9.68"7.14"7.71"11.32"4.64"7.82"3.33"4.38"12.58"117.63"
Pohnpei26.95"19.38"6.24"28.50"14.18"30.38"20.95"14.30"9.35"13.18"14.57"25.82"223.8"
Saipan7.43"2.30"3.15"0.86"2.02"2.85"5.71"10.94"10.95"8.62"10.63"7.76"73.22"
Yap16.99"12.85"7.24"8.63"17.78"8.59"10.35"10.13"12.84"12.55"13.00"5.68"136.63"
Pacific Island 1981-2010 Normal Median Precipitation (Inches)
Station Name Dec
2020
Jan
2021
Feb
2021
Mar
2021
Apr
2021
May
2021
Jun
2021
Jul
2021
Aug
2021
Sep
2021
Oct
2021
Nov
2021
Dec-
Nov
Chuuk11.25"10.10"7.25"8.32"12.47"11.30"11.66"11.98"12.86"11.71"11.51"10.61"136.77"
Guam NAS5.11"4.01"3.03"2.07"2.53"3.40"6.18"10.14"14.74"12.66"11.44"7.38"99.09"
Kapingamarangi9.84"9.15"9.27"11.43"13.64"12.08"13.78"14.15"8.13"9.93"8.19"9.27"145.85"
Koror11.16"10.18"8.56"7.44"7.32"11.83"17.48"18.53"13.50"11.77"11.84"11.39"152.90"
Kosrae16.11"16.67"12.93"16.06"17.51"17.75"14.64"14.91"14.22"14.22"10.94"13.83"213.87"
Kwajalein6.66"3.16"2.64"2.35"5.26"6.72"6.93"9.87"9.74"10.74"11.18"11.28"90.41"
Lukonor11.27"8.41"8.93"9.26"11.31"11.69"11.65"15.93"14.04"10.15"11.32"9.08"151.36"
Majuro11.39"7.74"6.88"6.58"9.42"10.11"11.01"11.17"11.69"11.17"12.73"13.44"125.25"
Pago Pago12.84"13.34"12.00"10.68"9.39"9.66"5.33"5.55"5.38"6.53"9.26"10.14"125.57"
Pohnpei16.08"13.18"9.55"13.17"18.41"19.96"14.81"15.43"14.26"12.55"15.27"14.83"182.36"
Saipan3.85"2.53"2.59"1.89"2.63"2.38"3.62"8.91"13.13"10.09"10.62"5.61"70.25"
Yap8.51"6.39"5.19"4.56"5.63"7.85"12.04"15.08"14.82"13.50"12.18"8.83"120.31"

As measured by percent of normal precipitation, Kapingamarangiwas drier than normal in the short term (November and the last 3 months [September-November 2021]) and long term (year to date [January-November 2021] and last 12 months [December 2020-November 2021]). Pago Pago was wetter than normal in November but drier than normal at the other 3 time scales. Kwajalein was drier than normal at long-term time scales and wetter than normal in the short term. Yap was drier than normal at short-term time scales and wetter than normal in the long term. Lukunor was drier than normal at the 3- and 11-month time scales and wetter than normal at the other 2 time scales. Airai and Saipan were drier than normal at one time scale and near to wetter than normal at the other 3 time scales. Chuuk, Guam, Kosrae, Majuro, and Pohnpei were near to wetter than normal at all 4 time scales.

Based on percent of normal average (instead of normal median values), in the Marianas Islands, precipitation during November was mostly above normal across the islands. A drier-than-normal pattern dominated across Rota and Saipan for the last 3 to 12 months. At longer time scales, precipitation was above normal at the southern extreme of Guam and northern extreme of Saipan, with below normal anomalies in between (percent of normal precipitation maps for the last 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 24, 36, 48, 60 months).

Based on percent of normal average (instead of normal median values), in the Marshall Islands, precipitation during November was mostly above normal across the islands. A drier-than-normal pattern began to appear in the northeast and southwest extremes of the islands at the 2-month time scale and spread across the northern and western islands by 5 months. This pattern continued through 36 months. Wetter-than-normal conditions dominated the plotted stations at longer time scales (percent of normal precipitation maps for the last 1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 24, 36, 48, 60 months).

According to the November 30th USDM produced for the USAPI, severe drought worsened to extreme drought in the southern FSM at Kapingamarangi, while abnormal dryness ended at Jaluit (RMI) and Nukuoro (FSM). The rest of the USAPI stations were free of drought and abnormal dryness. The National Weather Service (NWS) office in Guam issued two Drought Information Statements (DGT) for drought in November (on November 12 and 26) and one in early December (December 10) discussing the conditions in the USAPI. The presence of La Niña has produced very dry conditions for Kapingamarangi in Pohnpei state. Reports received by the NWS indicate that private water tanks were low, large community water tanks were around 80% capacity, and crops and vegetation were still yellowing. Storage in the Majuro reservoir held steady during the first half of November then slowly declined during the second half, dropping below the 28.8 million gallon threshold for concern during the last week of the month. Reservoir levels ranged from a peak of 32.85 million gallons on the 12th to a low of 26.47 million gallons on the 27th.

November 2021 precipitation ranks ranged from driest to wettest, but were mid-range at many stations. Dry conditions during previous months resulted in low ranks for some time periods for some stations:

  • Kapingamarangi: third driest November (in 33 years of data) and August-November and July-November; fifth driest October-November (30 years).
  • Lukunor: driest June-November (in 25 years of data), 2nd driest July-November, 6th driest August-November.
  • Yap: tenth driest November (71 years) and 9th driest June-November and May-November.
  • Pingelap: fifth driest August-November (36 years) in spite of November being the sixth wettest.
  • Ailinglaplap: third driest May-November (37 years).
  • Jaluit: fifth driest July-November (38 years) and ranks 6th or 7th or 9th driest for June-November thru December-November.
  • Kwajalein: ninth driest June-November (70 years).
  • Wotje: 7th driest February-November (36 years).

At the wet end of the scale, it was the wettest November on record at Woleai and Mili (38 years each).

The following analysis of historical data for the USAPI stations in the Global Historical Climatology Network-Daily (GHCN-D) dataset, augmented with fill-in data from the 1981-2010 Normals, helps put the current data into historical perspective by computing ranks based on the period of record. The table below lists the precipitation ranks for November 2021, June-November 2021 (last 6 months), and December 2020-November 2021 (the last 12 months). Some stations have a long period of record and their dataset is fairly complete, while other stations have a shorter period of record and the dataset has some missing data.

November 2021 USAPI Precipitation Ranks (1 = driest)
StationNovember 2021Jun-Nov 2021Dec 2020-Nov 2021Period of Record
RankYearsRankYearsRankYears
Ailinglaplap3338103726351981-2021
Airai1771476968691951-2021
Chuuk3671317065701951-2021
Fananu59--5--22003-2021
Guam4065486538641957-2021
Jaluit24386379351981-2021
Kapingamarangi3334205191962-2021
Kosrae3554344129341954-2021
Kwajalein567097017691952-2021
Lukunor323812523251981-2021
Majuro5768356862671954-2021
Mili38383636--331981-2021
Nukuoro2638273724361981-2021
Pago Pago3356205619551966-2021
Pingelap3237163629331981-2021
Pohnpei6871427067701951-2021
Saipan3441254120321981-2021
Ulithi2139--36--331981-2021
Utirik--18--8--41985-2020
Woleai3838252925261968-2021
Wotje253713368331981-2021
Yap107197052701951-2021
Map of U.S. Affiliated Pacific Islands November 2021 Precipitation (Inches)
Map of U.S. Affiliated Pacific Islands November 2021 Percent of Normal Precipitation
Map of U.S. Affiliated Pacific Islands September 2021-November 2021 Percent of Normal Precipitation
Map of U.S. Affiliated Pacific Islands January-November 2021 Percent of Normal Precipitation
Map of U.S. Affiliated Pacific Islands December 2020-November 2021 Percent of Normal Precipitation

SPI values for seven time periods for Pacific Islands, computed by the Honolulu NWS office.

SPI values for seven time periods for Pacific Islands

NOAA Regional Climate Centers

More information, provided by the NOAA Regional Climate Centers and others, can be found below.

Southeast

As noted by the Southeast Regional Climate Center, temperatures were below average across much of the Southeast region for the month of November and precipitation was well below normal across much the Southeast, with monthly totals ranging from 50 to less than 5 percent of normal. The driest locations were found across much of Virginia, North Carolina, South Carolina, Georgia, Alabama and Puerto Rico. Indeed, Danville, VA (1916-2021) and Hickory, NC (1949-2021) both observed their driest November on record, at 0.15 inch (3.8 mm) and 0.35 inch (8.9 mm) of precipitation, respectively. Macon, GA (1892-2021) measured only 0.29 inch (7.4 mm) of precipitation, which was more than 3 inches (76 mm) below average, making this the 2nd driest November on record. In contrast, the wettest locations for the month were located across most of the Florida Peninsula. San Juan, PR (1898-2021) tied for its second warmest November on record.

Drought intensified across North Carolina, South Carolina, Virginia, and Puerto Rico, and abnormally dry conditions (D0) increased in coverage across portions of Georgia and Alabama in November. At the beginning of the month, pockets of moderate drought (D1) were found in North Carolina and South Carolina. By the end of the month, these pockets expanded with some areas of severe drought (D2) developing in eastern North Carolina, southern Virginia and along the border of North and South Carolina. Areas of abnormally dry conditions (D0) developed across large portions of Alabama and Georgia. Drought conditions also increased across Puerto Rico, with much of the island in moderate drought (D1) ringed by abnormally dry conditions (D0). The citrus growing region of Florida received adequate rainfall this month, allowing farmers to ease up on irrigation. The drier weather towards the end of the month allowed farmers to harvest cotton as well as seasonal fruits and vegetables. In Georgia, the drier month allowed many farmers to make significant progress with cotton and soybean harvests. Winter wheat continued to be planted with some producers irrigating fields to help with their growth. Multiple counties experienced freezing conditions and their first frost of the season. Similarly in Alabama, the dry conditions allowed for producers to finish harvesting many crops. Farmers in South Carolina noted that strawberries were slightly behind due to the drier conditions, but pastures remained in good condition.

South

As explained by the Southern Regional Climate Center, November 2021 was mild throughout the Southern region, ranking from 28th warmest for Oklahoma at 51.3 F (10.7 C) to 40th coolest for Tennessee at 45.7 F (7.6 C). Overall, the region was 48th warmest on record, with an average temperature of 54.4 F (12.4 C). Across the region, precipitation ranked 13th driest historically. No measurable rainfall was recorded across a broad swath of the Texas and Oklahoma panhandles, with occasional reports of zero rainfall extending southward to the Rio Grande. For some stations near and west of Midland, there had not been measurable rainfall recorded since the first week of October.

The mild, dry weather led to substantial expansion of drought conditions across the Southern region. The percentage of the region in drought grew from 23% on November 2 to 42% on November 30, according to the USDM. Severe drought expanded from 4% to 12% during the same period. Drought grew in all six states, particularly along the Lower Mississippi River valley and in central and western parts of Texas and Oklahoma. Drought improvement was confined mostly to northern and southern Texas. The impacts of drought were primarily agricultural, with problems establishing the winter wheat crop and cool season forage. The wildfire risk also remains elevated. With a weak to moderate La Niña likely to persist until spring, continued drying is likely, especially for Texas.

Midwest

As described by the Midwest Regional Climate Center, precipitation was drier than normal during November across most of the Midwest and Midwestern temperatures were slightly below normal for November, with a notable east-west divide. Only isolated areas in northern Minnesota, northern Wisconsin, northern Michigan, and extreme northwest Missouri had above-normal precipitation. Average total precipitation for the region was 1.38 inches (35 mm), which was 1.16 inches (29 mm) below normal. All nine states had drier-than-normal monthly precipitation with totals ranging from 0.02 inch (1 mm) below normal in Minnesota to over 2 inches (51 mm) below normal in Illinois and Missouri. The largest precipitation deficits affected a swath from south-central Missouri to the northeast into Illinois and southern Wisconsin. Precipitation in this area was below 25 percent of normal for November. Illinois had the 9th driest November on record, dating back to 1895.

Drought continued to affect portions of the Midwest by late November, and most locations had little change in drought status throughout the last month. On November 30, about 17 percent of the region was in drought, which was a 2 percent improvement compared to early November. The most widespread severe conditions were in northern Minnesota, with moderate drought also impacting northern Wisconsin, the northern Illinois-southern Wisconsin border, and isolated areas in Iowa. Abnormal dryness was reported in about 22 percent of the Midwest on November 30, which was about a 4 percent expansion in dryness compared to early November. Most of the expansion in abnormal dryness during November was in Missouri. Over the entire fall (September-November), drought conditions showed considerable improvement. From early September to late November, drought was removed from 7 percent of the Midwest, including D4 (Exceptional Drought) being eliminated from the region. Drought conditions showed the most improvement in Minnesota and Iowa while conditions worsened throughout the fall in Wisconsin and northern Michigan.

By late November corn and soybean harvest was nearly complete across the Midwest. Corn harvest in Michigan, Minnesota, and Wisconsin was 6-14 percent ahead of the 5-year average, and all other states were near average for late November. Soybean harvest was slightly behind the 5-year average in Illinois, Indiana, Kentucky, Michigan, and Ohio, but progress accelerated compared to recent weeks due to below-average precipitation. Winter wheat emergence was 5 percent ahead of the 5-year average in Missouri and 2-5 percent behind the 5-year average in Illinois, Indiana, Michigan, and Ohio. Most of the winter wheat was in good to excellent condition across the region.

Northeast

As explained by the Northeast Regional Climate Center, November 2021 ranked as the Northeast's 16th driest November since recordkeeping began and the average temperature was 39.1 degrees F (3.9 degrees C), 0.3 degrees F (0.2 degrees C) cooler than normal. The Northeast picked up 12.83 inches (325.88 mm) of precipitation during autumn, which was 110 percent of normal, and this autumn was the fourth warmest autumn since 1895.

The USDM released on November 4 showed 1 percent of the Northeast in severe drought, 1 percent in moderate drought, and 5 percent as abnormally dry. Below-normal precipitation and declining soil moisture led to the expansion of abnormal dryness in West Virginia and southern/eastern Maryland. Drought and abnormal dryness persisted in far northern New England. The USDM released on December 2 showed 1 percent of the Northeast in severe drought, 1 percent in moderate drought, and 8 percent as abnormally dry.

High Plains

As summarized by the High Plains Regional Climate Center, November was a dry month for the High Plains with below-normal precipitation and above-normal temperatures across the region. As a result of these above-normal temperatures, many locations ranked in the top 10 warmest November on record and some areas broke daily records throughout the month.

Most of the region observed less than 50 percent of normal precipitation, aside from an area in northeastern North Dakota. The largest departures from normal were observed in southwestern Colorado, eastern Kansas, and eastern Nebraska with totals as much as 3.75 inches (95.25 mm) below normal. This large area of below-normal precipitation led to many locations ranking in the top 10 driest on record for November. Salina, KS observed a trace of precipitation for the month which tied as the 3rd driest November on record. Goodland, KS also received very little precipitation for November receiving 4 percent of normal precipitation. With 0.02 inch (0.50 mm) of precipitation for November, Goodland observed its 7th driest November on record tied with 2014 and 1950. This has led to crop concerns in Kansas as winter crops pull moisture from the soil due to lack of precipitation. This can lead to problems in the crop season next year as soil moisture will be less than optimal. Colorado, with the largest departure from normal precipitation for November, also observed some concerns. Several locations within the state recorded among their driest (November). Early season snowpack in the mountains is below normal for this time of year. An above-average snowpack is essential this year due to the current drought. Without the snowpack, water levels along the Colorado River will likely remain low. While it is still early in the season, the longer Colorado remains drier, the more precipitation later in the season it will take to make up the deficit. Despite a dry month, Northeastern North Dakota did receive above normal precipitation for November. While it was not enough to rank in the top 10 for the month, it did help contribute to a change from D1 to D0 drought conditions for that portion of the state.

Horticulturists in Wyoming are concerned after noticing trees beginning to bud as a result of above-normal temperatures in November. While the early budding or blooming can be a pretty sight, it can be damaging to the trees. When blooming early, a sudden drop in temperatures can cause shock to the tree. It can also cause the tree's flowers or fruits not to grow next year as they have exerted all of their energy in growing early. Concerns for tourism in western South Dakota have begun throughout November as it continues to be warm and dry in the region. Many commercial entities in the western portion of the state, such as the Black Hills, rely on business from winter sports. With the warm temperatures and lack of snow, opening dates have been pushed back without an indication of when they will be able to open. Warm temperatures have also impacted their ability to create synthetic snow, as temperatures 28 degrees F (-2.2 degrees C) or below are needed. Winter crops have also been impacted by warm, dry conditions. In Kansas, warm temperatures have caused winter wheat to grow more than it should. The additional plant height can cause an increased chance of problems with plant diseases and pests. Around mid-November the crops begin to become dormant, but the warm temperatures have helped crops continue to grow using current soil moisture. With drought conditions present, use of stored soil moisture is a concern as farmers look toward next year's crops.

Above-normal temperatures and below-normal precipitation for November led to reduced streamflow in areas across the region. In Montana, streamflow is below normal to much below normal across most of the state, with some gauges indicating record low streamflow. Below normal to much below normal streamflow can also be observed in portions of Nebraska, South Dakota, Wyoming, and Colorado, with record low streamflow for the month in areas of western South Dakota and Nebraska. In the lower Missouri River Basin, streamflow remains normal to above normal for most of the area with a few gauges indicating below normal streamflow.

Above-normal temperatures and dry conditions in the month of November led to the intensification of drought conditions. The southern part of the region saw an increase of severe drought (D2) and extreme drought (D3) as a result of these conditions. Despite this, the region remained free of exceptional drought (D4) conditions. Colorado experienced the most significant expansion in drought conditions, with D2 and D3 conditions increasing 22 percent during the month in the eastern part of the state. The entire state is now experiencing abnormally dry or drought conditions. Western Kansas observed the introduction of D3 and the slight increase to moderate drought (D1) and D2 conditions after receiving below 25 percent of their normal precipitation. In Wyoming, D3 was reduced slightly in the south-central part of the state but was introduced in the southeastern portion and expanded across the northern part of the state. While in North Dakota, D1 and D2 conditions were reduced in the eastern part of the state after above-normal precipitation this past month. Throughout the rest of the region, other minor improvements were observed. According to the U.S. Monthly Drought Outlook for December, drought development is likely in southern Colorado and southwestern Kansas.

West

As described by the Western Regional Climate Center, a blocking ridge of high pressure in the western US and deep low pressure centered over southcentral Alaska persisted for much of the month. This resulted in above-normal temperatures across the entire West with well-below-normal temperatures for Alaska, record-breaking in some cases. The storm track allowed for several moderate to strong atmospheric rivers to impact Oregon and Washington during November 10-16 with above-normal precipitation for the month in most of Washington. These storms brought flooding, mudslides, and strong winds to northern Washington. Few storms and little moisture occurred for the rest of the West leading to well-below-normal precipitation and a slow start to mountain snowpack accumulation.

Record warm temperatures were widespread across southern Nevada, southern California, and western Arizona. Warmth in California and the Southwest was accompanied by little to no precipitation for the region during November. Las Vegas, Nevada; Phoenix, Arizona; Los Angeles, California; and San Diego, California all logged zero precipitation for the month tying record low values at all four locations. Novembers with zero precipitation have happened in the past; for example, Los Angeles, California has had 15 Novembers with zero precipitation since 1877. Northern Washington was the one area of the West that was anomalously wet for the month with multiple moderate-to-strong atmospheric rivers impacting the region. Bellingham, Washington received a record-breaking 14.57 in (370 mm; 280% of normal) of precipitation for the month breaking the previous record of 11.6 in (295 mm) set in 1990. The Olympic Peninsula also saw well-above-normal precipitation; Quillayute, Washington logged 27.56 in (700 mm; 181% of normal) coming in as the second wettest since 1966. Seattle, Washington received 10.26 in (261 mm; 163% of normal) for the 5th wettest on record; this was the wettest Autumn on record for Seattle since 1945.

Drought conditions persisted throughout the month across most of the West due to warm and dry weather. At the end of November, 94% of the West was in drought according to the USDM with 14% of the region experiencing exceptional drought (D4). The only part of the West without any drought (D1-D4) or abnormal dryness (D0) is western Washington and a small portion of northwest Oregon. Drought conditions worsened throughout the month in parts of New Mexico, Wyoming, and Montana.

Most of Alaska saw well-below-normal temperatures with the exception of the northeast interior and panhandle that were near to slightly above normal. Southcentral and most of western Alaska was quite cold with monthly temperature anomalies ranging from -6 F to -20 F below normal. Dry conditions with below-normal precipitation accompanied the cold weather. Iliaman was the coldest record at 7.1 F (-13.8 C), -20 F (-11.1 C) below normal, and came in at the fourth driest on record with 0.11 in (2.8 mm; 5% of normal). Bethel was the second coldest on record since 1923 at 0.7 F (-17.4 C), -17.8 F (-9.9 C) below normal, and the ninth driest logging 0.16 in (4.1 mm; 9% of normal).

Across Hawaii precipitation was well below normal for the month with many long-term stations less than 50% of normal. Honolulu recorded 0.09 in (2.3 mm; 4% of normal) for the fourth driest since records began in 1942, Lanai City logged 0.21 in (5.3 mm; 8% of normal) for the fifth driest on record, and Molokai received 0.33 in (8.44 mm; 12% of normal) making it the fifth driest on record since 1949. Drought conditions continued to degrade with 57% of the state in drought (D1-D4) and 11% in extreme or exceptional drought (D3-D4).

Additional Resources


Citing This Report

NOAA National Centers for Environmental Information, State of the Climate: Drought for November 2021, published online December 2021, retrieved on January 20, 2022 from https://www.ncdc.noaa.gov/sotc/drought/202111.

Metadata

https://data.nodc.noaa.gov/cgi-bin/iso?id=gov.noaa.ncdc:C00675