NATIONAL STORM SUMMARY

 

APRIL 2018

 

1-8: Multiple rounds of showers and locally severe thunderstorms swept across areas from the central and southern Plains into the middle and southern Atlantic States, providing generally beneficial precipitation. Some of the heaviest rain fell in the Southeast, where 2- to 4-inch totals were common.  A few locations in northern Florida and the central Gulf Coast States received in excess of 10 inches.  Meanwhile, most of the Northeastern precipitation fell as rain, following the substantial, late season snowfall of March 31 – April 1.  In parts of the Northeast, heavy rain and melting snow led to sharp rises in river levels but further eased long-term drought.  Significant rain also soaked the Midwest, especially from Missouri to Michigan. Severe weather outbreaks across the South and lower Midwest peaked on April 2-3 and 5-6, with preliminary reports indicating that there were more than six dozen tornadoes during the 5-day period.  On April 2, two tornado related deaths were reported in St. Martin Parish, LA, followed the next day by a tornado fatality in Union County, SC.  Torrential rainfall accompanied the severe weather, especially on April 2, when daily-record totals included 9.10 inches in Alexandria, LA; 7.01 inches in Vicksburg, MS; 5.38 inches in Jackson, MS; and 5.07 inches in Del Rio, TX.  For Alexandria, it was the wettest April day on record, surpassing 8.55 inches on April 29, 1953.  It was also the wettest April day in Vicksburg, eclipsing 6.32 inches on April 29, 1991.  Heavy showers persisted across the South through April 3, where daily-record totals reached 3.69 inches in Baton Rouge, LA; 3.41 inches in Meridian, MS; and 2.70 inches in Tuscaloosa, AL.  In New York, daily record rainfall amounts for April 4 totaled 1.45 inches in Syracuse and 1.36 inches in Glens Falls.  Meanwhile, late season snow blanketed parts of the Northwest and the High Plains.  Record-setting snowfall for April 4 totaled 10.7 inches in Lander, WY, and 5.6 inches in Pueblo, CO.  Heavy rain quickly returned to parts of the South and Midwest by April 5, when daily-record totals climbed to 3.46 inches in Anniston, AL, and 2.01 inches in St. Louis, MO.  And, record-setting Eastern totals for April 6 included 1.58 inches in Buffalo, NY, and 1.56 inches at Virginia’s Dulles Airport.  Farther west, significant precipitation overspread northern California and environs on April 6, when Mt. Shasta City, CA, collected a daily-record total of 3.37 inches.  By April 7, heavy precipitation returned to other areas of the West, resulting in daily-record amounts in locations such as Quillayute, WA (2.58 inches); Bishop, CA (0.90 inch); and Pocatello, ID (0.64 inch).  Pocatello’s April

7-8 total reached 1.10 inches, including a trace snow.  High winds accompanied the late-week Northwestern storminess, with April 7 gusts clocked to 67 mph in Cut Bank, MT, and 61 mph in Hillsboro, OR.

 

9-15:  Periods of rain occurred in the Midwest.  There was a general northward shift in where the heaviest rain fell, with only light precipitation falling in much of the southern Plains.  Significant rain also fell across parts of the nation’s mid-section, especially from South Dakota to Texas. Record-setting rainfall totals for April 9 included 1.84 inches in Rhinelander, WI, and 1.26 inches in Billings, MT.  Significant, early-week rain also drenched the western Gulf Coast region and environs, with daily record totals reported on April 10 in Longview, TX (3.42 inches), and El Dorado, AR (2.32 inches).  Later, another wave of Western precipitation led to record-setting totals for April 12 in Mount Shasta City (1.73 inches) and Wenatchee, WA (0.59 inch).  Month-to-date rainfall through April 15 climbed to 6.98 inches (434 percent of normal) in Mount Shasta City and 1.66 inches (692 percent) in Wenatchee.  The 13th was the wettest April day on record in Fresno, CA, where 2.04 inches fell.  Previously, Fresno’s wettest April day had occurred on April 8, 1926, with a 1.81-inch total.  During the mid- to late-week period, showers and thunderstorms dotted the Plains and Midwest.  In Texas, daily-record amounts for April 12 included 1.47 inches in Midland and 0.79 inches in Lubbock.  Later, record-setting Midwestern rainfall amounts for April 15 totaled 2.25 inches in Dubuque, IA, and 1.57 inches in Oshkosh, WI.

 

16-22: Active weather, featuring several individual disturbances, resulted in showery conditions across large sections of the country. Periods of stormy weather extended eastward across the northern and central Rockies, as well as the northern Plains and upper Midwest.  Farther south, a late-week storm system brought heavy rain and cooler weather to a belt stretching eastward from the southern Plains and mid-South.  The rain, while disruptive to fieldwork, benefited emerging summer crops and further eased pockets of long-term Southeastern drought.  Elsewhere, much-needed rain developed on Sunday, April 23, across southern Florida, where several significant wildfires had previously flared. Ongoing showery weather in the Northwest led to record setting October-April precipitation in Seattle, WA.  Seattle’s total from October 1 – April 23 reached 44.63 inches (147 percent of normal), edging the October-April standard of 44.52 inches, set just last year in 2015-16.  Seattle also set a record of 143 days with measurable precipitation from October 1 – April 23, shattering the October-April standard of 137 days set in 1998-99 and 2010-11.  Meanwhile, multiple rounds of heavy rain struck the mid-South and environs.  On April 17, daily-record rainfall totals included 3.40 inches in Jacksonville (Little Rock Air Force Base), AR, and 2.36 inches in McAlester, OK.  Meanwhile, daily-record totals across the interior Northwest reached 0.51 inch (on April 17) in Spokane, WA, and 0.54 inch (on April 18) in Big Piney, WY.  On April 20, heavy showers in the Northeast resulted in the wettest April day on record in Buffalo, NY.  Buffalo’s total of 1.95 inches edged its April daily record of 1.77 inches, originally set on April 3, 1903.  On April 21, showers and thunderstorms erupted across the southern Plains and mid-South, resulting in daily-record totals in locations such as Tulsa, OK (3.19 inches); Fayetteville, AR (2.74 inches); and Cape Girardeau, MO (2.40 inches).  On the same date, snow blanketed northern New England, where Caribou, ME, received a daily-record sum of 4.1 inches.  In fact, Caribou noted measurable snow each day from April 1722, totaling 8.4 inches.  Meanwhile in southern Florida’s Big Cypress National Preserve, the Cowbell and Parliament fires each consumed more than 20,000 acres of vegetation.  Significant rain spread across southern Florida on April 23, with Southwest Florida International Airport in Fort Myers receiving 3.76 inches between midnight and 10 a.m., compared to 4.16 inches during the 204-day period from October 1, 2016 – April 22, 2017.

 

23-30: Major spring storms continued to produce extreme and unusual weather in several regions.  For example, early-week downpours in the southern Mid-Atlantic region led to flooding but further reduced the Southeastern drought’s footprint. Late in the week, a powerful spring storm emerged from the West.  Torrential rainfall developed from the southeastern Plains into the middle Mississippi Valley; severe thunderstorms erupted across the South; and heavy snow blanketed central and southern portions of the Rockies and High Plains.  Specific agricultural impacts from the late-week storm included localized wind damage and isolated tornadoes from eastern Texas into the lower and middle Mississippi Valley. Heavy snow in a narrow band across the central and southern Plains.  In particular, snowfall totals in excess of a foot across western Kansas and environs left rural roads impassable. The week began with beneficial rain falling across southern Florida, where record-setting rainfall totals for April 23 included 3.70 inches in Fort Lauderdale and 3.50 inches in West Palm Beach.  Farther north, the 24th was the wettest April day on record in Raleigh-Durham (RDU), NC, where 4.51 inches fell.  RDU’s previous wettest April day had been April 26, 1978, when 3.37 inches occurred.  In addition, RDU’s April 23-25 rainfall reached 7.45 inches.  In Haw River, NC, the Haw River rose 5.38 feet above flood stage to reach its highest level since March 2003.  Elsewhere in North Carolina, daily-record amounts for April 24 reached 3.67 inches in Wilmington and 2.74 inches in Fayetteville.  In neighboring Virginia, Danville received 5.53 inches from April 22-25, aided by a daily-record sum of 1.94 inches on the 24th.  Meanwhile, precipitation spread across the nation’s northern tier.  Snowfall totaled 3.3 inches (on April 25) in East Rapid City, SD, and 4.7 inches (on April 26) in Grand Forks, ND.  It was the snowiest day in Grand Forks since December 6, 2016, when 8.8 inches accumulated.  Farther south, daily-record rainfall totals for the 26th topped 2 inches in locations such as Fayetteville, AR (2.93 inches) and West Plains, MO (2.16 inches).  Pounding rainfall would return to the same region just 3 days later, on April 29, when West Plains netted 6.94 inches.  Rainfall in West Plains totaled 11.36 inches during the last 5 days of the month, boosting its monthly sum to 17.93 inches (400 percent of normal).  Daily-record amounts for April 29 climbed to 4.75 inches in Mount Ida, AR; 4.52 inches in Joplin, MO; 4.46 inches in Columbia, MO; 4.31 inches in Springfield, MO; 2.83 inches in Evansville, IN; 2.81 inches in Tulsa, OK; and 2.47 inches in Quincy, IL.  Heavy snow began to blanket parts of the Intermountain West on April 28, when Riverton, WY, received a dailyrecord sum of 9.5 inches.  At week’s end, rain changed to snow across the High Plains, where Dalhart, TX, measured 9.0 inches on April 30.  With the bulk of the Plains’ snow occurring on Sunday, April 30, additional details will appear next week.  Meanwhile, serious flooding developed in the mid-South and lower Midwest.  In Missouri, for example, the Current River surged to record-high levels in Van Buren (17.20 feet above flood stage on April 30) and Doniphan (20.13 feet above flood stage on May 1), surpassing high-water marks originally set in March 1904.  Elsewhere in Missouri, record-setting crests were also established in late April or early May along rivers such as the

Gasconade, Meramec, and St. Francis Rivers.

 

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