North American Drought Monitor - July 2020 - Drought.gov

North American Drought Monitor – July 2020
At the end of July 2020, moderate to extreme drought (D1-D3) affected 14.7% of the area
and 14.9% of the population of North America. The percent area value was 2.3% more than
the value for the end of June 2020. The percent population value was 3.5% more than the
value for the end of June. At the end of July, 59.8% of the Rio Grande/Bravo River Basin,
23.9% of the Columbia River Basin, and 26.6% of the Great Plains were in moderate to
extreme drought, and 13.4% of the Great Lakes Basin was in moderate to severe drought
(D1-D2). The North American Great Plains extends across the United States and into
adjacent parts of northeast Mexico and the southern Prairies of Canada. The percent area
values for the Great Lakes and Rio Grande/Bravo River Basins increased this month, while
the values for the Columbia River Basin and Great Plains decreased compared to the end of
June.

CANADA:

National Overview

July precipitation was near normal throughout much of Canada except for southern British
Columbia and parts of Quebec and Atlantic Canada. Despite late-month rainfall in Ontario
and parts of Quebec, drought conditions remained largely unchanged in that region due to an
intense dry spell with abnormally high temperatures in late June and early July. Western
parts of the Atlantic region continued to receive well-below-normal precipitation,
intensifying the drought conditions throughout the region. In the Prairies, convective storm
events brought adequate precipitation to most areas. Abnormally Dry (D0) conditions and
pockets of Moderate Drought (D1) persisted as water supplies and pastures continued to show
drought impacts. In British Columbia, dry summer conditions persisted throughout the
southern parts of the province, resulting in little change to the drought conditions. Fifteen
percent of the country was classified as either abnormally dry or in drought; this includes
twenty-eight percent of the agricultural landscape.

Pacific (BC)

Drought and abnormally dry conditions throughout British Columbia remained relatively
unchanged. Impacts of the below-normal precipitation throughout much of the southern part
of the province were minimized by good moisture levels prior to July. The eastern portion
of Vancouver Island continued to experience below-normal precipitation, not only for the
month of July, but also over the last 6 months. These factors were taken into consideration
as Abnormally Dry (D0) conditions were expanded and a pocket of Moderate Drought (D1)
was added in the Courtenay and Port Alberni region. Abnormally Dry (D0) conditions
emerged along the Alberta/B.C. border region from Fernie to Crowsnest Pass, given satellite
data indicating this area as being dry. In addition, an area in the interior stretching from
Anahim Lake to Chilko Lake was identified as having 50-75 percent of normal precipitation
in the last 90 days; a pocket of D0 was expanded as a result. Although conditions have not
changed drastically in the last 30 days, the patch of Abnormally Dry (D0) conditions and
Moderate Drought (D1) remained in place around Penticton and Osoyoos. While the
southern portion of the province received below-normal rainfall, central and northern areas
continued to receive substantial precipitation. Areas such as Haida Gwaii saw the removal
of Abnormally Dry (D0) conditions due to abundant precipitation through the northern and
coastal regions. Compared to last month, there was only a one percent increase in
Abnormally Dry (D0) and Moderate Drought (D1) conditions across the province.

Prairies (AB, SK, MB)

Most of the Prairie region continued to receive adequate rainfall, including localized
convective storm activity. However, a few pockets of the region remained Abnormally Dry
(D0) or in Moderate Drought (D1). Overall drought in the region has improved despite
emerging dry conditions in southeastern Manitoba. Approximately six percent of the Prairie
region was classified as either Abnormally Dry (D0) or in Moderate Drought (D1); this
includes fourteen percent of the region’s agricultural landscape. As of the end of July, the
Prairie region contained only two small regions of Moderate Drought (D1), as the Severe
Drought (D2) regions previously in southeastern Saskatchewan improved. Several
Abnormally Dry (D0) pockets developed despite general improvement through the region.
The southern foothills and mountain region in western Alberta received below-normal
precipitation, resulting in an abnormally dry classification. The southwestern portion of
Saskatchewan showed below-normal precipitation and topsoil moisture shortages for hay and
pasture, resulting in the classification of Abnormally Dry (D0) around Maple Creek, Swift
Current, and the Cypress Hills region. In addition, short- and long-term dry conditions in
southeastern Saskatchewan have resulted in poor pastures and water-supply concerns,
resulting in redevelopment of an Abnormally Dry (D0) classification. The long-standing
pocket of drought and abnormally dry conditions in northern Alberta was removed, given
adequate precipitation over the last 2 months. In Manitoba a pocket of Moderate Drought
(D1) emerged around Winnipeg due to significant dryness reported over the last 3-6 months.

Central (ON, QC)

High temperatures and precipitation deficits through the first half of July intensified drought
conditions across much of southern Ontario and Quebec; Abnormally Dry (D0), Moderate

Drought (D1), and Severe Drought (D2) conditions persisted across the region. Over twenty-
six percent of the region was classified as abnormally dry or in drought, including sixty-four
percent of the region’s agricultural landscape. Conditions were not much better in
northwestern Ontario, where long-term precipitation deficits persisted from Atikokan to
Thunder Bay and Nipigon. Data indicated that this area only received 50-75 percent of
normal precipitation since November 2019; as such, D0 and D1 conditions remained in this
area. Two pockets of Moderate Drought (D1) were added in southern Ontario, one from
London to Burlington, the other from Newmarket to Belleville, as multiple drought indicators
including SPI, SPEI, and precipitation percentiles indicated dry conditions in the past 2
months. Significant dryness also persisted in an area surrounding Ottawa and south towards
of Granby, Quebec, leading to the expansion of Severe Drought (D2) conditions. While areas
in central Quebec saw improved moisture during July, data indicated this area is still
experiencing some surface soil moisture and groundwater deficits. Thus, Moderate Drought
(D1) was improved in the area but Abnormally Dry (D0) conditions remained in place.
Various data also indicated the northern portion of Quebec received between 50-100 percent
below normal precipitation in the last 3 months, leading to the addition of Abnormally Dry
(D0) and Moderate Drought (D1) conditions.

Atlantic (NB, NS, PEI, NL)

While there was slightly improved precipitation in parts of New Brunswick and across the
Gaspé Peninsula of Quebec in July, the region was still suffering from significant
precipitation deficits. Twenty-four percent of the region was classified as either Abnormally
Dry (D0), in Moderate Drought (D1), or in Severe Drought (D2); this includes more than
eighty-six percent of the region’s agricultural landscape. In the past 3-6 months, the lowest
possible SPI and SPEI values were recorded; this translates to 40-60 percent of normal
precipitation in the past 2-3 months. Additionally, streamflow levels were very low across
nearly all New Brunswick and into P.E.I., specifically around Summerside and
Charlottetown. These areas also recorded Extremely Low to Exceptionally Low Percentile
values in the past 6 months. Given these factors, two areas of Severe Drought (D2) were
added across the Atlantic region: one stretching from the Gaspé peninsula towards Grand
Falls and Edmundston, while the other includes Moncton, Bouctouche, and the western edge
of P.E.I. An additional pocket of Abnormally Dry (D0) conditions was also added to the
western portion of Newfoundland.

Northern (YT, NWT)

In general, the territories have seen improvement in precipitation over the past month. The
D0 surrounding Whitehorse, Yukon was removed as well as the pocket of D0 near Inuvik,
NWT. Abnormally Dry (D0) conditions have also improved from Yellowknife towards
Great Bear Lake as a result of the improved precipitation values. However, an area in the
northeastern part of the Northwest Territories was identified as being drier than normal,
according to satellite data. A patch of Abnormally Dry (D0) conditions was added from Fort
Good Hope, north along the Mackenzie River. Only twelve percent of the region was
classified as Abnormally Dry (D0) for the month of July.

UNITED STATES: During July, monthly temperatures averaged at least 5.0°F (more than
2.8°C) above normal in several locations across southern New Mexico and western Texas,
as well as an area covering the lower Great Lakes States, central Appalachians, and
Northeast. In contrast, cooler-than-normal conditions were mostly limited to the northern
High Plains and the Northwest.

Most of the country’s drought remained consolidated across the western half of the United
States, although secondary drought areas existed in the western Corn Belt and from the lower
Great Lakes region into the Northeast. Well over one-half (59 percent) of the 11-state
Western region was in drought on July 28, according to the U.S. Drought Monitor. On the
same date, drought covered 29 percent of the Northeast but only 11 percent of the Midwest.
Nationally, nearly one-third (33 percent) of the contiguous U.S. was experiencing drought
by July 28, up from 26 percent at the end of June. National drought coverage was last greater
in September 2018.

Tropical systems affecting the United States during July included Tropical Storm Fay and
Hurricane Hanna. Fay produced heavy rain and gusty winds in the Atlantic Coast States and
on July 10 became the first tropical cyclone to make landfall in New Jersey since Irene on
August 27, 2011. About 2 weeks later, on July 25, Category 1 Hurricane Hanna moved
inland across southern Texas. Hanna resulted in local flooding in the lower Rio Grande
Valley and caused some wind damage to commodities such as citrus and cotton. On July 29-
30, newly formed Tropical Storm Isaias sparked locally heavy showers across Puerto Rico
and the U.S. Virgin Islands, easing or eradicating drought.

Abnormal dryness (D0) returned across parts of southern Alaska, covering about 5 percent
of the state by July 28. Farther south, drought coverage in Hawaii slightly decreased, from
23 to 21 percent, during the 4-week period ending July 28. Meanwhile, drought in Puerto
Rico—which had peaked at 60 percent coverage on June 23—fell to 45 percent by July 28
and completely disappeared the following week, after the passage of Tropical Storm Isaias.

Historical Perspective: According to preliminary data provided by the National Centers for
Environmental Information, the contiguous U.S. experienced its 11th-warmest, 43rd-wettest
July during the 126-year period of record. The nation’s monthly average temperature of
75.7°F (24.3°C) was 2.1°F (1.1°C) above the 1901-2000 mean, while precipitation averaged
2.93 inches (74.4 mm)—105 percent of normal. It was the country’s wettest July since 2015.

Statewide temperature rankings ranged from the 47th-coolest July in Idaho to the hottest July
on record in seven East Coast States from Virginia to New Hampshire. In addition, July
average temperatures were among the ten highest values on record in seven other East Coast
States (all except Georgia), along with Vermont, West Virginia, two Midwestern States
(Michigan and Ohio), and three Southern States (Arizona, New Mexico, Texas). Meanwhile,
statewide precipitation rankings ranged from the sixth-driest July in Arizona to the seventh-
wettest July in Kansas. Arizona, with its second-hottest July behind only 2003, was the only
state to appear on the top-ten lists for both heat and dryness.

Agricultural, Hydrological, and Wildfire Highlights: Midwestern drought was most
apparent from northeastern Nebraska into central Iowa and across easternmost corn and

soybean production areas. Nevertheless, 72 percent of nation’s corn and 73 percent of the
soybeans were in good to excellent condition on August 2, according to the U.S. Department
of Agriculture. On the same date, roughly three-quarters of the U.S. rice (76 percent) and
peanuts (73 percent) were rated good to excellent.

Meanwhile, some crops across the central and southern High Plains continued to suffer from
the effects of heat and drought, despite a turn toward cooler, wetter weather as the month
progressed. By August 2, Colorado led the country in very poor to poor ratings for sorghum
(26 percent) and corn (25 percent), while Texas led with 24 percent of its cotton rated very
poor to poor.

In the West, heat- and drought-related stress extended to rangeland and pastures. In early
August, Oregon led the country with 70 percent of its rangeland and pastures rated in very
poor to poor condition, followed by California (55 percent), Wyoming (53 percent), New
Mexico (47 percent), and Colorado (41 percent). However, drier-than-normal weather also
favored Northwestern small grain maturation and harvesting.

By August 2, topsoil moisture was rated at least two-thirds very short to short in several
Western States, including New Mexico (82 percent), California (75 percent), Oregon (73
percent), Washington (69 percent), and Wyoming (68 percent). Colorado led the Plains with
topsoil moisture rated 64 percent very short to short, followed by Texas at 63 percent.
Similarly, Iowa led the Midwest with topsoil moisture rated 47 percent very short to short.
In the Northeast, topsoil moisture was at least one-half very short to short in Connecticut,
Delaware, Maine, New Hampshire, Pennsylvania, and Rhode Island. Nationally, topsoil
moisture was 36 percent very short to short in early August.

On July 28, nearly one-fifth (19 percent) of the nation’s corn production area was in drought,
up from 6 percent on June 30. Similarly, the portion of U.S. soybeans in drought climbed
from 2 to 16 percent between June 30 and July 28. However, hay in drought increased only
slightly (from 18 to 21 percent) during the 4-week period, along with the U.S. cattle inventory
in drought (from 24 to 28 percent).

On August 1, statewide reservoir storage in the western United States as a percent of average
for the date was mostly near or above normal. However, storage was slightly below average
in California, Colorado, and Oregon, and significantly below average in New Mexico.

Meanwhile, wildfire activity in the United States overall remained below average in most
parts of the country through July and into early August. By August 10, year-to-date wildfires
had burned about 2.3 million acres (more than 935,000 hectares), well below the 10-year
average of more than 4.3 million acres (about 1.75 million hectares). In early August, nearly
four dozen wildfires—in various stages of containment—were active across the western half
of the country. One of the most destructive wildfires, the 32,000-acre (13,000-hectare) Apple
Fire, was started on July 31 in Riverside County, California, by a vehicle’s exhaust system.

MEXICO: During July, one of the summer months in the Northern Hemisphere, the most
important rainfall at the national level was directly associated with Tropical Cyclone Hanna.

Despite the above-average rainfall in the northeast and central-north, July 2020 precipitation
averaged 120.9 mm at the national level, just at 87.1% of the 1981-2010 average, and was
ranked as the 23rd-driest July according to data since 1941.

Other above-normal rainfall areas were located in Chihuahua, Sinaloa, Nayarit, Colima,
Jalisco, Hidalgo, State of Mexico, Morelos, Tlaxcala, Veracruz, Oaxaca, and Campeche;
most of them because the monsoon development and trough lines, as well as 13 tropical
waves producing convection from the Gulf of Mexico, the Caribbean Sea, and the Pacific
Ocean. According to rainfall classification at the state level, Morelos recorded its second-
rainiest July since 1941, Colima its third wettest, and Nuevo León its fourth wettest. For the
May-July period, the Yucatan Peninsula states had their wettest period on record, mainly due
to rains caused in June by Tropical Storm Cristobal.

Thanks to the much-needed rainfall in July 2020 in the northeast, the area in moderate to
severe drought (D1-D2) in southern Coahuila and northern Zacatecas was erased. Likewise,
the area with these drought categories in Durango decreased, dropping from 50.5% of the
state at the end of June, to 33.2% on July 31. In Sinaloa, moderate drought coverage (D1)
decreased from 20.1% at the end of last month to 3.7%. In Michoacán and Tlaxcala, a
decrease in moderate drought (D1) of 22.5% and 27.0% respectively was observed; Colima
no longer has a footprint of drought or dryness. Areas of abnormally dry conditions (D0) in
southern Nuevo León, southeast Tamaulipas, parts of San Luis Potosí, and southern Durango
were eliminated over the last month.

On the other hand, conditions worsened in the Baja California Peninsula, most of the
northwest, the east, the Gulf of Mexico slope, the South Pacific region, and the Yucatan
Peninsula, because of very low July precipitation. The states of Veracruz and Tabasco
recorded their third- and fifth-driest July since 1941, respectively. In the last 3 months (May
to July), the state of Oaxaca had its fourth-driest such period, Guerrero and Hidalgo their
sixth driest, and Tlaxcala and Michoacán their seventh driest, as during this period the Pacific
side of southern Mexico received very low rainfall amounts.

As described above, the scarce rains favored the development of extreme drought (D3) in
southeastern Oaxaca. Meanwhile in Guerrero, the D2-D3 area increased from 30.9 to 45.6%
compared to a month ago. In southern Veracruz, the emergence of moderate drought (D1)
was noted, while abnormally dry conditions emerged in Chiapas, as well as southern
Quintana Roo. In the north, the severe drought (D2) area increased in Chihuahua from 6.9
to 10.7% by the end of July, while D2 areas emerged in northern Coahuila.

The national mean temperature in July 2020 was 26.7°C, 3.0°C above the 1981-2010
average. This ranked as the warmest July according to records from 1953, surpassing the
record of July 2019 record of 26.5°C. The most significant anomalies in the mean
temperature (up to 5.0°C above average) were noted in the Baja California Peninsula, the
northern and eastern parts of the country, and Durango and northern Oaxaca. At the state
level, the states of Coahuila, Mexico City, Hidalgo, Puebla, Querétaro, San Luis Potosí,
Sonora, Tabasco, and Veracruz achieved their warmest July.

Regarding drought impacts on the Pacific side, the population around the Cuitzeo Lake basin
expressed their concern about the decrease in water level in the aquifer for this body of water,
according to studies carried out by the Natural Resources Research Institute (Inirena) of the
Universidad Michocana de San Nicolás de Hidalgo; the main concern is for agricultural and
urban use, with precipitation deficits aggravating the situation.