May 2013 Weather Highlights for West-Central Texas
Precipitation for May varied from well-above to well-below normal across west-central Texas (Figure 1).
Figure 1: Percent of Normal Precipitation for May, 2013.
Most of the above normal monthly precipitation was across parts of the Concho Valley, Heartland, Northern Edwards Plateau, and Northwest Hill Country. Some locations within the aforementioned areas received more than 5 inches of rainfall. While the monthly precipitation was below normal at scattered locations in central and southern sections of west-central Texas, the most concentrated area with below normal amounts was across Big Country, northeastern Concho Valley and northern Heartland. Within the aforementioned areas, the monthly rainfall was less than 1 inch at some locations.
At Abilene Regional Airport, the average temperature for May was 73.0 degrees. This equaled the normal average temperature for May. Total precipitation for Abilene in May was 2.00 inches. This was 1.18 inches below the normal of 3.18 inches.
At San Angelo Regional Airport, the average temperature for May was 74.9 degrees. This was 0.4 degrees above the normal average temperature of 74.5 degrees. Total precipitation for San Angelo was 3.57 inches. This was 0.75 inches above the normal of 2.82 inches.
The number of days in May with high temperatures of 100 degrees or more include:
4 at San Angelo, 3 at Abilene, and 2 at Junction.
The rollercoaster pattern in temperatures (from April) continued into the first few days of May. With the exception of the northern Big Country, high temperatures were in the 90s on the 1st.
With the approach of a strong cold front into a rather unstable airmass, numerous strong to severe storms occurred during the evening and nighttime hours of the 1st. Most of the severe storms were in the Big Country and Concho Valley. Significant wind damage occurred in Albany (Shackelford County), with roofs blown off of a factory and a house. In addition, multiple large trees and power lines were blown down. Abilene Regional Airport recorded a peak wind gust of 47 mph. The largest hail of golfball size was reported one mile south-southwest of Echo (Coleman County). The below radar animation (Figure 2) shows the development and coverage of storms between 7 PM and 11 PM, on May 1st.
Figure 2: Animated National Weather Service San Angelo Radar Imagery, for May 1.
A number of storms contained heavy rain. Rainfall amounts of 1-2 inches (with a few locally higher amounts) occurred at scattered locations, mainly across central and southern sections of west-central Texas.
Much cooler air invaded the region behind the strong cold front, accompanied by gusty north winds. A peak wind gust of 45 mph was recorded at Abilene. With extensive cloud cover, daytime temperatures only reached the upper 40s to mid 50s on the 2nd. These temperatures were 35-45 degrees colder than on the previous day. As an unusually strong high pressure system settled south into western Texas, clearing skies allowed temperatures to dip into the 30s, for early morning lows on the 3rd. The low temperature of 33 degrees at Abilene and 35 degrees at San Angelo were not only records for that date, but also tied the record low temperatures for the month of May. At four cooperative observer locations in west-central Texas, low temperatures at or below 32 degrees were reported. This likely was the latest freeze on record for those locations.
Temperatures rebounded quickly, and highs were mostly in the upper 70s to lower 80s on the 4th.
Light rain showers occurred on the 6th with the arrival of a weak upper level disturbance. Rainfall at some locations across the southern Big Country, northern and western Concho Valley, was between one tenth and one quarter of an inch.
A cluster of thunderstorms dissipated after moving east into the northwestern Big Country, during the overnight hours of the 7th and 8th. Parts of Fisher County received between one quarter and three quarters of an inch of rainfall.
With the approach of a dryline into a very unstable airmass, a few thunderstorms developed in northwestern Texas on the 8th, and became severe. One of the severe storms tracked east across northern Fisher and Jones Counties during the evening hours. In Fisher County, the storm produced golfball to baseball size hail 1-2 miles north of Rotan, and a funnel cloud was reported 8 miles east of Rotan. In Jones County, this storm was prolific in producing hail. Quarter to golfball size hail was reported in Hamlin, with enough hail to cover the ground. Hen egg and tennis ball size occurred with this storm just north and northwest of Anson, with golfball size hail in the town of Anson. This large hail covered the ground.
The below radar animation (Figure 3) shows the development and track of storms between 4:15 PM and 8:15 PM, on May 8th.
Figure 3: Animated National Weather Service San Angelo Radar Imagery, for May 8.
Another storm dissipated while tracking east into Haskell County. One half to one inch of rainfall occurred with the storm in Fisher and Jones Counties.
May 9th was very active with thunderstorms in west-central Texas. This occurred as upper level disturbances moved northeast into Texas and interacted with moist and increasingly unstable air. Later in the day, a cold front approached the area from the north, while a dryline approached from the west. Showers and thunderstorms with heavy rain occurred on the morning of the 9th, primarily across the Concho Valley and Heartland areas. One of the storms produced quarter size hail in Brookesmith (Brown County).
Strong to severe thunderstorms affected the northern half of west-central Texsas during the afternoon. Additional strong to severe thunderstorms affected the southern half of west-central Texas during the evening and early nighttime hours. Most notable were 2 fairly long-track supcercell severe storms.
In Nolan County, large hail to golfball and hen egg size was reported around Sweetwater. Quarter to walnut size hail was also reported with this storm in northern and northeastern Nolan County. In western Taylor County, quarter size hail was reported from this storm (8 miles east-northeast of Nolan).
One of the supercell severe storms moved east across the northern half of Coke County, and then tracked southeast across Runnels and the southern half of Coleman counties. The radar animation in Figure 4 (below) shows the track of this supercell storm.
Figure 4: Animated National Weather Service San Angelo Radar Imagery, for May 9 (between 3:15 PM and 6 PM).
This storm produced quarter to golfball size hail in Coke County. In Runnels County, this storm produced golfball and hen egg size hail near Hatchell, and golfball to baseball size hail 3 miles north-northeast of Ballinger. A couple of utility poles and power lines were blown down on the west side of Ballinger. In Coleman County, golfball size hail was reported 6 miles southeast of Voss, and baseball size hail was reported in Gouldbusk.
Another of the supercell severe storms tracked southeast, from southwestern Concho County across Menard and Mason Counties. The radar animation in Figure 5 (below) shows the track of this supbercell storm.
Figure 5: Animated National Weather Service San Angelo Radar Imagery, for May 9 (between 5:45 PM and 9 PM).
In Coleman County, ping-pong ball size hail was reported from this storm, 2 miles west of Live Oak. This storm produced golfball size hail 6 miles north-northwest of Menard, and 1 mile north of Menard. This caused damage to numerous cars along U.S. Highway 83. The largest reported hail with this storm was baseball to softball size, 5-7 miles east of Menard. Tennis ball size hail was reported at Hext. In Mason, this storm produced golfball to billiard ball size hail 9 miles south-southeast of Mason. Car windows were broken by hen egg size hail in western Mason County (2 miles east-northeast of Erna). Near the town of Mason, strong winds blew a police car off of Rural Route 783.
Another severe storm produced quarter to golfball size hail in Menard County. The track of this storm is also shown in Figure 5, between 7 PM and 8:15 PM.
In all, a total of 39 severe weather reports were received for the May 9th event.
With an upper level disturbance lifting northeast across the region, numerous showers and thunderstorms also occurred on May 10th. Severe weather (large hail and damaging winds) occurred with a supercell storm which was along a cold front, as the front tracked southeast across central sections of west-central Texas. The radar animation in Figure 6 (below) shows the track of this supercell storm.
Figure 6: Animated National Weather Service San Angelo Radar Imagery, for May 9 (between 2 PM and 4:45 PM).
The largest hail was ping-pong ball size, which was reported 12 miles southwest of Ballinger and at Rowena (Runnels County), and 2 miles southeast of Voca (Mcculloch County). Telephone poles were blown down along U.S. Highway 67 in Runnels County, 4 miles east of Rowena. In addition, a 6-inch diameter tree limb was blown down along U.S. Highway 83 in Runnels County, 10 miles north of Paint Rock.
Most locations across west-central Texas received rainfall on May 9-10. This rainfall was of some short-term benefit to the region.
Dry weather with cool nights and pleasant daytime temperatures occurred on May 11-12. Temperatures were warmer on the 13th and 14th, with an increase in moisture across the area on the 14th.
As a larger upper level disturbance lifted northeast into Texas, a large area of showers and thunderstorms developed and move east across west-central Texas, from the late evening of the 14th into the post-Midnight hours of the 15th. The heavier rainfall (one half to one inch with locally higher amounts) occurred across much of the Concho Valley. This rainfall was of some short-term benefit to the Concho Valley. Figure 7 (below) shows rainfall amounts across west-central Texas, for the 24-hour period ending at 7 AM on May 15th.
Figure 7: West-Central Texas Rainfall for the 24-hour period ending at 7 AM, May 15.
Another severe weather event occurred on the 15th, mostly across the Big Country and Heartland areas. As a strong upper level disturbance lifted northeast into western Oklahoma, another disturbance moved southeast into Texas from New Mexico. A dryline advanced east across western sections of west-central Texas. Another surface boundary was aligned north-northeast to south-southwest, across the far eastern part of west-central Texas. This setup, along with very unstable air ahead of the dryline, set the stage for thunderstorm development. Thunderstorms initially developed across the Big Country during the afternoon. An isolated storm affected far southeastern Brown County during the early evening. Thunderstorms developed south into the northern Concho Valley late in the evening. Between 10 PM and Midnight, a band of storms moved south across parts of the Heartland. A number of storms were severe.
Much warmer and summerlike temperatures occurred on the 16th to 20th. A weak upper level high pressure system moved east across Texas on the 17th. New record high temperatures of 106 degrees at San Angelo, and 104 degrees at Abilene, were set on the 17th. In addition, record high minimum temperatures at Abilene were set on the 18th and tied on the 19th. At San Angelo, record high minimum temperatures were set on the 18th and 20th. The coverage of showers and thunderstorms was considerably lower on the 16th to 20th. Isolated showers and thunderstorms occurred across parts of the Northwest Hill Country on the 16th. On the 17th, estimated 60 mph wind gusts were reported from a severe thunderstorm at Richland Springs, in San Saba County. A few other showers and thunderstorms occurred in central and eastern sections of west-central Texas on the 17th. On the 18th, a severe storm produced golfball size hail 3 miles north of Weinert, and baseball size hail 6 miles east-northeast of Weinert, in Haskell County.
With the approach of an upper level disturbance and a dryline into a very unstable airmass on May 20, persistent and regenerating severe thunderstorms occurred in Brown County during the afternoon and evening hours. The storms produced three tornadoes, along with funnel clouds and large hail. The second tornado caused the most damage, and was rated EF-1 on the Enhanced Fujita Scale. The largest hail was golfball size, reported at Lake Brownwood, 2 miles east of Zephyr, and 5 miles northeast of Zephyr. Heavy rainfall occurred from the regenerating storms. Figure 8 (below) shows rainfall amounts for the 24-hour period ending at 7 AM on May 21.
Figure 8: Rainfall for the 24-hour period ending at 7 AM, May 15.
Rainfall amounts between 1.5 and 3 inches occurred in eastern Brown County, with more than 3 inches along part of the border with Brown and Comanche Counties.
With the arrival of an upper level disturbance from the west, scattered showers and thunderstorms occurred in the Big Country, along and behind a southward-moving cold, on May 21. With the exception of some locations across Haskell and Throckmorton Counties, most locations received less than one half inch of rainfall. Between one half and 1.5 inches occurred in parts of Haskell and Throckmorton Counties. The cold front brought a brief intrusion of cooler air into west-central Texas. Gusty north winds followed passage of this cold front, and a peak wind gust of 40 mph was recorded at the Abilene Regional Airport.
As a weak high pressure system settled south into the area behind the front, clear skies and light winds allowed temperatures to dip into the 50s for early morning lows on the 22nd, across most of west-central Texas. The coolest lows were 46 degrees at South Llano State Park (4 miles south-southwest of Junction), and 48 degrees at Eden. A strong temperature recovery ensued, and afternoon highs on the 22nd were in the 90s.
A significant severe weather event occurred on the evening and nighttime hours of May 23. With a very unstable airmass, thunderstorms developed near an outflow boundary and rapidly became severe across northwestern Texas. This complex of severe storms moved south across the Big Country during the evening and early nighttime hours. A weak tornado affected the east and southeast sides of Roby (Fisher County) resulting in tree damage and minor roof damage.
Strong winds and large hail also accompanied the severe storms across the Big Country. A peak wind gust of 62 mph occurred at the Abilene Regional Airport. This thunderstorm complex continued to move south across central and southern sections of west-central Texas, during the overnight hours of the 23rd and 24th. Strong thunderstorm winds downed a few tree limbs 8 miles west-northwest of Coleman (Coleman County), and damaged part of a metal roof of a home between Carlsbad and Grape Creek (Tom Green County).
Heavy rainfall from this thunderstorm complex caused some flooding in various parts of west-central Texas. Roads were flooded with 1-2 feet of water in Rotan (Fisher County). Street flooding was reported in San Angelo. In Menard County, a bridge along Highway 83 was impassible due to high water, 3 miles north of Menard. A section of U.S. Highway 190 west of Menard was also impassible, due to high water. In Kimble County, Rural Route 21 was closed at Bear Creek, due to flooding.
In all, a total of 64 severe weather and flash flood reports were received for this event.
Although the heavy rainfall resulted in some flooding, the widespread coverage was beneficial for much of west-central Texas, where drought conditions have been ongoing. Figure 9 (below) shows the rainfall amounts for the 24-hour period ending at 7 AM on May 24.
Figure 9: Rainfall amounts for the 24-hour period ending at 7 AM, May 24.
Rainfall amounts of 1-3 inches were common across much of the Concho Valley, parts of the western and eastern Big Country, parts of the western Heartland, parts of the Northern Edwards Plateau, and much of the Northwest Hill Country. Rainfall of 3-5 inches occurred in scattered pockets of the Concho Valley and Northwest Hill Country. The highest rainfall amounts, between 5 and 6 inches, occurred in parts of southern Concho and Menard Counties.
Temperatures were much cooler on the 24th, with mostly cloudy skies. Highs ranged from the mid 70s to mid 80s across most of west-central Texas. Showers lingered across southern sections of west-central Texas during the morning, while additional showers and thunderstorms developed across eastern sections of the region during the late morning and afternoon hours. This was associated with an upper level disturbance, which slowly exited the area Rainfall amounts of one half to one inch occurred at scattered locations across the eastern Big Country, Heartland and Northwest Hill Country.
Scattered showers occurred across roughly the eastern third of west-central Texas on the morning of the 25th.
An area of showers and thunderstorms overspread the Concho Valley and Northern Edwards Plateau, during the post-Midnight hours of the 26th. This area of showers and storms moved across the Northwest Hill Country during the early morning hours. rainfall was locally heavy across the western Concho Valley and Northern Edwards Plateau. Figure 10 (below) shows rainfall amounts across west-central Texas, for the 24-hour period ending 7 AM, on May 26th.
Figure 10: West-Central Texas Rainfall for the 24-hour period ending at 7 AM, May 26.
Some locations across these areas received 1-2 inches of rainfall, with localized amounts over 2 inches. In the San Angelo area, rainfall amounts were mostly between one quarter and three quarters of an inch.
A humid airmass occupied the region during the last several days of May. Showers and thunderstorms occurred in parts of the western Concho Valley and northern Crockett County on the 27th. Showers and storms also occurred on the 28th, with scattered locations west of a Sweetwater to Christoval line receiving one half to one inch. The Abilene Regional Airport recorded a peak wind gust of 51 mph from a dissipating nearby thunderstorm. Outside of the showers and storms, gusty south to southeast winds occurred across west-central Texas on the 28th. A peak wind gust of 41 mph occurred at Junction. Isolated showers and thunderstorms occurred just south of Abilene, across Taylor and Callahan Counties, on the 30th. With these nearby storms, a peak wind gust of 47 mph was recorded at the Abilene Regional Airport.
With a combination of increasing south winds during the overnight hours, moist air, and patchy low cloud cover, a record high minimum temperature (75 degrees) was tied at San Angelo on the 31st.