NATIONAL WEATHER SUMMARY JULY

JULY 2023

2-8: Variable showers east of the Rockies benefited summer crops, some of which were progressing through the heat- and moisture-sensitive reproductive stage of development. However, some areas—including much of Texas and parts of the upper Midwest—received little or no rain.

Heavy rain across portions of the central Plains, central Corn Belt, and Northeast benefited corn, soybeans, and other summer crops. Parts of the South also received meaningful rain, providing some relief during a string of hot, humid days. In contrast, dry weather— accompanied by locally elevated temperatures—prevailed in much of the West. Across the interior Northwest, hot, dry weather stressed some springsown crops. Meanwhile, late-week heat in the Southwest signaled a slightly delayed monsoon arrival, following last year’s unusually early onset. During the first full week of July, hot weather dominated the western, eastern, and southern U.S. Weekly temperatures averaged more than 5°F above normal in several areas, including the Northeast and the Pacific Northwest. In southeastern Arizona, southwestern New Mexico, and western Texas, pre-monsoon heat led to temperatures averaging at least 5°F above normal. Conversely, readings averaged 5°F or more below normal across large sections of the northern and central Plains and the western Midwest.

In Illinois, some of the heaviest rain fell in Chicago, where daily-record totals included 4.68 inches at Midway Airport and 3.35 inches at O’Hare Airport. Heavy rain also soaked the Northeast on July 2, when daily-record amounts reached 3.30 inches in Hartford, CT, and 2.24 inches in Worcester, MA. By Independence Day, July 4, showers lingered in the South and East, while a new area of significant precipitation developed across the north-central U.S. It was the wettest Fourth of July on record in several communities, including Hattiesburg, MS (2.33 inches); Mitchell, SD (1.41 inches); and Buffalo, WY (1.23 inches). Soon, rain expanded to other parts of the central and eastern U.S., with daily-record totals reaching or exceeding the 2-inch mark in locations such as Monticello, AR (2.90 inches on July 6); Reading, PA (2.39 inches on July 7); Houston, TX (2.18 inches on July 6); and Wichita, KS (2.00 inches on July 5). Some thunderstorms contained high winds and large hail, with some of the most notable severe weather occurring on July 2 in the middle Atlantic and Southeastern States; several tornadoes were observed as far north as Pennsylvania. Early-week heat was focused across the West and Deep South.

Western daily-record highs for July 2 reached 111°F in Kingman, AZ, and 109°F in downtown Sacramento, CA. Meanwhile, daily records across the nation’s southern tier included 95°F (on July 2) in Key West, FL, and 99°F (on July 3) in Corpus Christi, TX. Florida’s heat further intensified by July 4, as it became the hottest Independence Day on record in Brooksville (99°F, tying 1927); Tampa (97°F); and Naples(96°F, tying 1998). Heat also expanded in the West, with records for July 4 being set in Eugene, OR (98°F), and Quillayute, WA (93°F). Pacific Northwestern heat generally peaked on July 5, when daily-record highs in Oregon rose to 99°F in Eugene and 98°F in Portland. On the other side of the northern Rockies, however, cool air spread southward. By July 5, Miles City, MT, reported a daily-record low of 46°F. July 6 featured a slew of daily-record lows, including 35°F in Hibbing, MN; 44°F in Sisseton, SD; and 45°F in Valentine, NE. Later, additional records across the nation’s mid-section dipped to 47°F (on July 7) in Cedar Rapids, IA, and 53°F (on July 8) in Garden City, KS. In contrast, portions of the West, South, and East continued to experience hot weather. In the Northeast, temperatures topped the 90-degree mark from July 5-7 as far north as Maine, where Caribou (91°F) registered a daily-record high on the 6th. Eastern heat was particularly persistent in southern Florida, where Miami tallied a trio of daily-record highs (95, 97, and 96°F) from July 6-8. In the Florida Keys, Marathon closed the week with five consecutive daily-record highs (95, 96, 95, 96, and 97°F) from July 4-8. Elsewhere, late-week heat also affected in parts of the Southwest, where daily-record highs surged to 110°F (on July 6) in Tucson, AZ, and 109°F (on July 7) in El Paso, TX.

9-15: Hot, dry weather gripped the West and much of Texas, while scattered to widespread showers and thunderstorms affected much of the central and eastern U.S. Excessive rain fell in a few areas, including parts of the Northeast, while daily severe-weather outbreaks from the Plains to the East Coast resulted in localized wind and hail damage.

East of the Rockies, some of the driest areas stretched from western, central, and southern Texas to the western Gulf Coast region, as well as portions of the northern Plains and far upper Midwest. For the second week in a row, heat was focused across the West, East, and South. Meanwhile, lingering cool weather across the Plains, Midwest, and mid-South held temperatures to nearor below-normal levels, with weekly temperatures averaging at least 5°F below normal in parts of eastern North Dakota and northern Minnesota. In contrast, extreme heat from the Desert Southwest to the western and central Gulf Coast States boosted temperatures 5 to 10°F above normal. Other areas reporting significantly above-normal temperatures included southern Florida, New England, and the Northwest. Blazing heat shifted as the week progressed, eventually taking aim on the West. Temperatures continued to top the 100-degree mark in much of Texas, but triple-digit heat appeared in much of California and the Great Basin. As late-week temperatures soared in the Desert Southwest, readings topped 120°F at a few low-elevation sites. On July 15, Phoenix, AZ, recorded its 16th consecutive day with a high temperature of 110°F or greater, approaching that city’s longest such streak on record—18 days in a row from June 12-29, 1974. Elsewhere in Arizona, Kingman (114°F on July 15) set its all-time station record, surpassing 113°F on July 17, 2005, and June 20, 2017. Meanwhile, unusually warm water near the Florida Keys contributed to the highest-ever temperature in Marathon, with a high of 99°F on July 13. Marathon’s reading tied 99-degree temperatures on July 17, 1972, and July 15, 1987. The remainder of southern Florida also experienced above-normal temperatures, with temperatures soaring to daily-record levels in locations such as Miami (96 and 97°F, respectively, on July 11 and 12); Vero Beach (96°F on July 9); and Melbourne (96°F on July 9). Parts of Texas also continued to weather extreme heat, especially around the middle of the week. On July 12, for example, daily-record highs in Texas surged to 110°F in Midland and Lubbock. Wichita Falls, TX, registered a dailyrecord high of 110°F on July 13. In contrast, cool Midwestern weather led to daily-record lows in locations such as Mason City, IA (48°F on July 9); Grand Forks, ND (42°F on July 11); and Hibbing, MN (39°F on July 12). At week’s end, Western heat intensified. From July 13-15, Phoenix tallied a trio of daily-record highs (114, 116, and 118°F). In California, record-setting highs for July 15 topped the 110-degree mark in Needles (121°F), Imperial (116°F), Barstow-Daggett (116°F), Lancaster (112°F), Paso Robles (112°F), and Palmdale (111°F). Farther north, triple-digit, dailyrecord highs for the 15th included 106°F in Reno, NV, and 105°F in Dallesport, WA. Reno followed that reading with a high of 108°F on July 16, tying an all-time station record.

16-20: Some areas east of the Rockies—including the northern Plains, upper Midwest, and south-central U.S.— missed out on the rain, resulting in varying degrees of stress on rain-fed summer crops. Farther west, a weak and erratic monsoon circulation delivered spotty Southwestern showers, but most of the western U.S. experienced hot, dry weather. Weekly temperatures averaged 5 to 10°F above normal in many locations from California to Texas, including the Desert Southwest. Still, given the bounteous 2022-23 Western winter wet season, the onset of significant and widespread wildfire activity has been delayed. Through July 24, U.S. wildfires had charred fewer than 874,000 acres, just 25 percent of the 10-year average of 3.5 million acres. Elsewhere, weekly temperatures averaged at least 5°F below normal across portions of the northern Plains and upper Midwest, with slightly cooler-than-normal conditions extending across the remainder of the Corn Belt. Hot, humid conditions across the Deep South helped to hold temperatures above 70°F all week from central, southern, and eastern Texas to the southern Atlantic Coast. In Key West, FL, where records go back more than 150 years, a low temperature of 87°F on July 18 tied an all-time station mark. Similarly, readings remained above 80°F at lower elevations of the Desert Southwest, with Phoenix, AZ, reporting a low of 97°F—highest minimum temperature on record in that location—on July 19. In Phoenix, where the temperature last fell below 90°F on July 9, several other records were set. For example, July 22 was the 23rd consecutive day in Phoenix with a maximum temperature of 110°F or greater, surpassing an 18-day streak from June 12-29, 1974. Additionally, Phoenix noted highs of 115°F or greater on each of the 6 days from July 17-22, tying a record initially set from June 15-20, 2021. The heat wave in Phoenix peaked with highs of 119°F on July 19-20, leaving only three hotter days on the books: 122°F on June 26, 1990; 121°F on July 28, 1995; and 120°F on June 25, 1990. All-time records were approached or tied in several other Western locations, including Grand Junction, CO, where the high of 107°F on July 17 matched the station record originally set on July 9, 2021. Reno, NV, also tied a station record, posting a high of 108°F on July 16. Death Valley, CA, topped the 120-degree mark each day starting July 14, peaking at 128°F on the 16th. Minimum temperatures in Death Valley remained above 100°F on July 17 and 18. At times, triple-digit, daily-record highs extended into the Northwest and Southeast. In the latter region, July 21 featured dailyrecord highs for St. Simons Island, GA (102°F), and Tallahassee, FL (100°F). Meanwhile, Northwestern daily-record highs included 101°F (on July 16) in Burns, OR, and 101°F (on July 20) in Ellensburg, WA. California’s heat generally peaked late in the week with daily-record highs of 120°F (on July 21) in Palm Springs and 113°F (on July 22) in Redding. Late-week heat also expanded across the northern High Plains, where Helena, MT (103°F), collected a daily-record high for July 22. In contrast, cool weather in the upper Midwest led to scattered dailyrecord lows, including a reading of 48°F (on July 17) in Sisseton, SD.

23-29: Organized rainfall was scarce west of the Mississippi Valley, with elevated temperatures combining with the dryness to increase stress on a variety of crops.

Meanwhile, persistently hot, dry weather has plagued the western Gulf Coast region since mid-June, leading to drought development and crop stress. More recently, record-setting warmth arrived at the end of June in the Southwest, with an erratic monsoon circulation failing to deliver much, if any, rain. Weekly temperatures averaged 5 to 10°F above normal in the Southwest and at least 5°F above normal across portions of the northern and central Plains and western Corn Belt.

mostly dry weather has dominated California, the Great Basin, and the Northwest in recent weeks, leading to a seasonal increase in wildfire activity and declining rangeland and pasture conditions. By the end of July, the York Fire—straddling the California-Nevada line about 50 miles northwest of Needles, CA, had scorched more than 70,000 acres of desert vegetation in becoming the nation’s largest wildfire of the year to date. Farther north, the Golden Fire near Bonanza, OR—ignited on July 22—charred only 2,137 acres but damaged or destroyed at least 117 structures. Finally, the Eagle Bluff Fire, first reported on July 29, burned more than 15,000 acres near Oroville, WA, before leaping across the international border into southwestern Canada. Farther south, the hottest month on record wound down in locations such as Phoenix, AZ; Tucson, AZ; Las Vegas, NV; and El Paso, TX. Phoenix became the first major U.S. city to report a monthly average temperature exceeding the 100-degree mark; the July average of 102.7°F (7.2°F above normal) easily surpassed the August 2020 standard of 99.1°F. Tucson (94.2°F, or 6.0°F above normal) also toppled an August 2020 record (92.0°F). With a July average temperature of 97.3°F (4.1°F above normal), Las Vegas edged its July and all-time monthly record of 96.2°F, set in 2020. El Paso, with a July average of 91.6°F (7.2°F above normal), easily shattered its monthly record of 88.9°F, set in June 1994 and July 2020. Phoenix set several other records, including its longest streak with high temperatures of 110°F or greater. That streak, which ran 31 days from June 30 – July 30, surpassed the former Phoenix standard of 18 days, set from June 12-29, 1974. During the last full week of July, dozens of dailyrecord highs were established across the South and West. On July 23, tripledigit, daily-record highs included 105°F in Grand Junction, CO, and 104°F in Salt Lake City, UT, and Reno, NV. In near-coastal Texas, Victoria set a July record with 19 days of triple-digit heat, clipping the mark of 18 days set in 1914 and 1938. By July 24, heat expanded across the High Plains, resulting in daily-record highs in locations such as Hobart, OK (109°F), and Havre, MT (104°F). In northern Texas, Borger closed the month with 9 consecutive triple-digit readings, including a daily-record high of 107°F on July 24. Meanwhile in southern Florida, oceanic warmth contributed to the hottest day on record in Marathon (99°F on July 24, tying three other dates), as well as the hottest month on record in locations such as Marathon, Miami, and Key West. Due to competition from historic, late-July heat waves, only a handful of daily records were set in the Midwest. However, Sioux Falls, SD, posted a daily-record high of 104°F on July 27. In Kansas, Russell topped the 100-degree mark on 6 of the last 7 days of the month, including a daily-record high of 107°F on July 28. Late in the week, extreme heat persisted from the southern half of the Plains to the Mississippi Delta, with daily-record highs reaching 109°F (on July 28) in Concordia, KS, and 101°F (on July 29) in Baton Rouge, LA. In addition, Baton Rouge tied a 1921 record with 5 days of 100-degree heat in July.

 

Jim G. Munley, jr.
http://www.jimmunleywx.com