NATIONAL WEATHER SUMMARY

MARCH 2018

4-10: A much more tranquil weather pattern developed across the nation, allowing Midwestern floodwaters to recede. Like last year, the Southeast’s sudden reversal in early spring temperatures (generally 5 to 10F below normal for the week) followed record-setting February warmth.  Farther west, critically dry conditions persisted on the drought stricken southern High Plains, aggravated by above-normal temperatures.  According to the U.S. Drought Monitor, exceptional drought (D4) made its first appearance in Oklahoma since May 5, 2015.  Warmth continued through a second consecutive week on the central and southern Plains. Temperatures returned to near-normal levels in much of the West, following an extended cool spell, but remained as much as 5 to 15F below normal across the northern High Plains and parts of the Great Basin.  Cold weather lingered early in the week across the West.  Following a heavy snow event, Eureka, NV, posted a trio daily record lows (-11, -15, and -6F) from March 5-7.  Similarly, Winslow, AZ, collected consecutive daily-record lows (12 and 8F, respectively) on March 5-6.  Farther east, high winds raked the central Plains, following the departure of a low-pressure system.  On March 6, peak gusts in Kansas were clocked to 69 mph in Goodland and Garden City.  McCook, NE, reported a gust to 65 mph.  From Kansas southward, the wind raised dust, caused some travel disruptions, and fanned several grassfires. In advance of the windstorm, temperatures had briefly risen to 80F as far north as Russell, KS, where a daily-record high was tied on March 4.  Several days later, warmth returned to the south-central U.S., with temperatures soaring to 90F or higher in the lower Rio Grande Valley.  On March 10-11, Harlingen, TX, registered consecutive daily-record highs (90 and 97F, respectively).

 

11-17: Elevated temperatures (as much as 5F above normal with readings peaking above 80F), high winds, and low humidity levels on the southern High Plains resulted in blowing dust, a rash of grassfires, and further deterioration in the condition of rangeland, pastures, and winter grains.  From Nebraska northward, however, rain and snow maintained generally favorable conditions for winter wheat.  Farther east, relative normalcy returned to the Midwest, several weeks after a severe, late-winter flood struck the Ohio Valley and environs.  Cold air in the storm’s wake drained deep into the Southeast, resulting in a multi-day freeze event as far south as northern Florida that peaked on March 15.  Southeastern weekly temperatures averaged as much as 10°F below normal.  Owing to the record setting February warmth that preceded the March cold snap, producers monitored Southeastern ornamentals, blooming fruits, and recently emerged crops for any signs of freeze injury.  Warmer air returned across the Southeast at week’s end, accompanied by rain showers. Early in the week, hot weather affected the lower Rio Grande Valley.  Record-setting highs for March 11 included 101°F in McAllen; 97°F in Harlingen; and 95F in Brownsville.  A day later, record-breaking warmth briefly arrived across the Pacific Northwest.  In Washington, daily-record highs for March 12 rose to 73F in Seattle and 71F in Olympia.  In contrast, high temperatures on March 12 only rose to 38F in Danville, VA, and Raleigh-Durham, NC.  Elsewhere in Virginia, Blacksburg (30F) failed to reach the freezing mark on the 14th, following a 4.9-inch snowfall on March 12.  After mid-week, warmth developed across the south-central U.S.  Dodge City, KS, collected a daily-record high of 84F on March 15.  The following day, record-setting highs in Texas soared to 88F in Austin and 85F in College Station.  Farther east, daily-record lows in Florida for March 16 dipped to 33°F in Vero Beach and 34F in Fort Pierce.

 

18-24: Warm, mostly dry weather persisted across the southern Plains and the Desert Southwest, leading to further drought intensification.  Weekly temperatures averaged 5 to 10F above normal in a broad area covering the southcentral U.S., and briefly topped 90°F as far north as southwestern Kansas.  Elsewhere, stormy weather dominated the Pacific Coast States, with multiple rounds of heavy precipitation striking California.  California’s precipitation caused local flooding but further improved water-supply prospects.  Other areas of the West, excluding the southern tier of the region, also received significant rain or snow. Early-week warmth stretched across the Deep South in advance of a cold front.  Daily-record highs for March 18 included 94°F in Del Rio, TX, and 85F in New Iberia, LA, and St. Simons Island, GA.  On March 19, Galveston, TX, achieved a monthly record high of 89F.  Previously, Galveston’s highest March temperature had been 87F on March 15, 2008.  Elsewhere on the 19th, New Iberia notched another record (86F), while Vero Beach, FL, tallied a daily-record high of 89°F.  On March 20, lingering warmth across southern Florida resulted in a daily-record high of 89°F in Miami.  Later, warmth returned and intensified across the south-central U.S.  In Texas, Midland posted consecutive daily-record highs (91 and 90F, respectively) on March 22-23.  Other record-setting highs for March 23 included 91F in Amarillo, TX, and Garden City, KS.  Heat also developed in the Southwest, where Tucson, AZ, registered a daily-record high (91F) for March 22.  In contrast, the Far West experienced a lingering cool spell.  In California, daily-record lows for March 18 dipped to -2F in South Lake Tahoe and 37°F in Santa Barbara.  Several days later in Oregon, record-setting lows for March 24 were set in locations such as Burns (13F) and Klamath Falls (18F). 

 

25-31: Little or no precipitation on the central and southern High Plains.  As a result, most rangeland, pastures across the High Plains’ core drought area continued to experience significant stress, especially given the continuation of warm weather.  Meanwhile, mostly dry weather returned to California, the Great Basin, and the Intermountain West, following a month-long period of late-season storminess that substantially improved runoff prospects and snowpack. Elsewhere, unusually cold weather and periods of snow prevailed across the northern Plains and upper Midwest, while mostly dry weather covered southern Florida and the mid-Atlantic coastal plain.  Weekly temperatures averaged more than 5F below normal across large sections of Montana and North Dakota, as well as parts of the upper Mississippi Valley, but ranged from 5 to 10F above normal in portions of California and from the southern Rockies to the Mississippi Delta. Warmth prevailed across the South in advance of the rain.  In Texas, record-setting highs for March 25 soared to 94F in San Angelo and 90°F in Midland.  Later, warmth replaced previously cool conditions in the Far West.  However, lingering cold weather resulted in daily-record lows in locations such as Klamath Falls, OR (14F on March 25), and Montague, CA (21F on March 26).  Later, from March 28-30, San Francisco Airport tallied a trio of daily-record highs (77, 81, and 79F).  Consecutive daily-record highs were established on March 29-30 in California locations such as Salinas (86 and 87F, respectively) and Monterey (82 and 83F, respectively).  In southern California, record-setting highs included 99°F (on March 30) in Thermal and 97°F (on March 31) in Needles.  In stark contrast, high temperatures failed to reach the 20-degree mark on March 31 in Montana locations such as Turner (12F) and Livingston (19F).  Livingston also posted a daily-record low (4F) for March 31.

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