Climate Summary for May 2012

May 2012 Weather Highlights for West-Central Texas

 ...8th Warmest May on Record for Abilene...

Temperatures averaged above normal across west-central Texas in May. 

Precipitation for the month varied from well-above to well-below normal.  The 
monthly amounts were above normal across the southwestern Big Country, and along an
arc extending from Crockett County northeast into Tom Green County, and from Tom 
Green County east and southeast across Mcculloch, San Saba, and Mason Counties. 
Scattered pockets within this arc received more than 200 percent of the normal 
monthly rainfall. The rainfall for May was below normal across a small part of the 
northern Concho Valley, northern Heartland, and much of the Big Country.  This was 
most pronounced across part of the northern Big Country, where the monthly amounts 
were less than 25 percent of normal.

At Abilene Regional Airport, the average temperature for May was 76.6 degrees.  
This was 3.6 degrees above the normal average temperature of 73.0 degrees.  This
marks the 8th warmest May on record for Abilene.  Total precipitation for 
Abilene in May was 2.31 inches.  This was 0.87 inches below the normal of 3.18 
inches.

At San Angelo Regional Airport, the average temperature for May was 77.0 degrees. 
This was 2.5 degrees above the normal average temperature of 74.5 degrees.  This 
tied for the 11th warmest May on record for San Angelo.  Total precipitation for San
Angelo was 4.50 inches.  This was 1.68 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, 4 at Junction, and 3 at Abilene.

May 2012 Weather Highlights...

Well-above normal daytime temperatures occurred on several days early in the month.
Highs were mostly in the range of 95-104 degrees on the 4th-6th. Record high minimum
temperatures were set at Abilene and San Angelo on the 2nd.  A record high minimum 
temperature was set at Abilene on the 3rd.  Record high temperatures were tied at 
San Angelo and Abilene on the 4th. Gusty south winds occurred on some of the days.  
Peak wind gusts of 40 mph were recorded at Junction on the 3rd, and 44 mph at 
Abilene on the 5th.    

With the approach of a dryline into a rather unstable airmass, scattered severe 
thunderstorms occurred on the 3rd through 6th, as upper level disturbances moved 
across the region in southwest flow aloft.

The severe storms on the 3rd produced large hail and occurred in the late evening, 
across the northern Big Country. The largest hail reported hail size was golfball 
size in Haskell County (6 miles northeast of Rule and 2 miles south-southwest of 
Weinert).

On the 4th, the severe storms occurred mostly during the evening, across the eastern
Big Country and into Brown County.  Golfball size hail in Cross Plains caused 
extensive damage to vehicles.  Wind damage was also reported in Cross Plains.  Ping
Pong ball size hail was reported in Albany. 

The severe storms on the 5th occurred mostly during the evening, across parts of the
Heartland and Northwest Hill country.  Wind damage to a tree and power lines was 
reported in Brownwood, and hail to golfball size was reported 5 miles south-
southeast of Brownwood.  Ping pong ball size hail was reported 8 miles west of 
Zephyr (Brown County).          

On the 6th, a severe storm produced large hail as it tracked from Menard County into
eastern Kimble County.  Golfball size hail was reported in Menard County 13 miles 
southeast of Menard and 6 miles north of London.  Golfball size hail was also 
reported in London (Kimble County).     

A severe weather event affected a larger part of west-central Texas on the 7th, as a
cold front moved south into a moist and rather unstable airmass.  The severe storms 
occurred during the afternoon hours, and contained large hail and damaging winds.  
The large hail ranged from quarter to golfball size, with the golfball size reported
in Erna (Menard County).  Near San Angelo, quarter to half-dollar size hail was 
reported.  Strong thunderstorm winds uprooted trees in Fredonia (Mason County).  A 
70 mph wind gust was reported in Eden, and a 60 mph wind gust was recorded at 
Junction.  At the San Angelo Regional Airport, a 45 mph wind gust was recorded. 

The storm coverage on the 7th was widespread across roughly the southern half of 
west central texas, and heavy rainfall accompanied the storms.  Although beneficial 
overall, the heavy rainfall caused flash flooding in parts of Tom Green County, 
including the San Angelo area.  A number of water rescues were reported at various 
locations across San Angelo.  In addition, flooding was reported 3 miles west of 
Tankersley on Highway 67, and 1 mile south-southeast of Tankersley on FM Road 2335.

Additional showers and thunderstorms developed during the early morning hours of the
8th, as a weak disturbance aloft entered the region in southwest flow aloft.  The 
heavier rainfall occurred across parts of the Concho Valley and Heartland, and much
of the area along and south of Interstate 10.

Temperatures were much cooler on the 8th, with cloudy skies and rainfall.  Highs 
were in the 60s across much of west-central Texas.  A record low maximum temperature
was set at San Angelo on the 8th.

A heavy rain event occurred on the 10th, with the approach and arrival of an upper 
level storm system from northern Mexico.  A large area of showers and thunderstorms
overspread west-central Texas, and a few of the storms were severe.  Strong 
thunderstorm winds caused considerable localized damage to a ranch just west-
northwest of Wall (Tom Green County).  Lightning injured a person 9 miles south of 
Sweetwater.  Flooding was reported on a road 12 miles north of Barnhart, and on 
Highway 67 about 1 mile southwest of Barnhart.  

The heaviest rainfal with this event occurred across the western Big Country, Concho
Valley, Northern Edwards Plateau, and across the area southeast of a line from 
Junction to Richland Springs.  This rainfall on recently saturated soil led to 
greater water runoff into streams, lakes, and rivers.  Some water level increase in 
area reservoirs occurred as a result of this rainfall and runoff.

Rainfall totals for the period May 7-11 were in the range of 3-5 inches (with 
locally higher amounts) across the western Big Country, much of the Concho Valley 
and southern Heartland, and much of the Northern Edwards Plateau and Northwest Hill 
Country.  Rainfal amounts were mostly in the 1-3 inch range across the central and 
eastern Big Country, Runnels County, and the northern Heartland.  

Scattered showers and thunderstorms occurred across roughly the northern half of 
west-central Texas on the 11th, as the upper level storm system moved northeast to 
the Red River.  Considerable cloud cover lingered on the 12th.  This resulted in 
another cool day across west-central Texas, with afternoon highs in the upper 60s to
lower 70s across much of the region north of Interstate 10.

Numerous showers and thunderstorms occurred on the 14th and 15th, as a strong upper 
level disturbance moved from New Mexico southeast across Texas. Rainfall amounts of 
one half to one inch occurred across much of the Concho Valley, Northwest Hill 
Country, parts of the Northern Edwards Plateau, and southern Coleman County.  
Scattered locations received between 1.5 and 2.5 inches.  The Big Country received 
the least rainfall from this system, where the coverage was scattered and rainfall amounts 
varied under one half inch.

With the cumulative effects of rainfall from previous weeks, some water runoff 
into area streams, lakes, and reservoirs occurred.

Warmer and drier conditions occurred from the 15th to 21st, under the influence of 
weak upper level high pressure systems. Hotter daytime temperatures occurred on the 23rd 
and 24th. On the 23rd, highs were in the mid to upper 90s. On the 24th, highs ranged from 
the upper 90s to 105 degrees. An intrusion of very dry air followed a dryline, which entered 
the western Big Country on the afternoon of the 23rd, and advanced across roughly the western 
two-thirds of west-central Texas on the 24th. Afternoon relative humidity values dropped 
below 20 percent behind the dryline on the 23rd. On the 24th, relative humidity values fell 
into the 5-15 percent range behind the dryline.

A severe weather event occurred across the Big Country and parts of the Heartland 
areas on the 28th (Memorial Day).  With the approach of a weak cold front into a 
very unstable airmass, scattered thunderstorms developed by late afternoon across 
northwestern Texas.  These storms entered the Big Country and became more numerous 
during the evening hours.  Some of the storms moved southeast across the northern 
Heartland, while other storms lingered over the Big Country until after Midnight.

A number of the storms were severe with strong, damaging winds and large hail.  The 
severe weather affected Abilene and Brownwood.  In Abilene, most of the wind damage 
was to tree limbs and power lines.  Wind equipment measured peak gusts of 63 mph at 
Dyess Air Force Base, and 59 mph at the Abilene Regional Airport.  In Brownwood, the
winds downed trees and power lines.  Wind equipment measured a peak gust of 55 mph 
at Lake Brownwood. 

The largest hail size reported was golfball size at Nolan and 2 miles northwest of 
Winters. 

In all, a total of 18 severe weather reports were received for this event.

Locally heavy rainfall also accompanied the storms, and rainfall amounts of one half
to one inch were common where the storms occurred.  The highest amounts, between 1.5
and 3 inches, occurred across eastern Haskell and western Throckmorton Counties, and
across parts of Nolan and western Taylor Counties. 

Temperatures were hot on the 29th and 30th.  Highs were between 97 and 102 degrees 
at a number of locations areawide on the 29th, and across central and southern 
sections of west central texas on the 30th.

A significant severe weather event occurred on the evening and early nighttime hours
of the 30th.  With the approach of a dryline into a very unstable airmass, scattered
thunderstorms initially developed and became severe across the southern Big Country.
Hail to baseball size was reported at coronado camp, which is 9 miles southwest of 
View in Taylor County.  Golfball size hail occurred 12 miles west of Buffalo Gap 
(Taylor County), and at Lake Abilene State Park (4 miles southwest of Buffalo Gap).

During the evening and early nighttime hours, a supercell storm tracked south  
along an outflow boundary, from northern Runnels County into central Mason County.
This storm produced a couple of tornadoes along with baseball to grapefruit size 
hail. 

A brief tornado touchdown occurred in the Millersview area.  This tornado, which 
remained in open fields, was rated an EF0 on the Enhanced Fujita Scale.  Two other 
tornado touchdowns were reported on the Concho and Runnels County line just east of 
U.S. Highway 83, or about 5 miles east-northeast of Paint rock.  These tornadoes 
also occurred over an open field, and were also given EF0 ratings on the Enhanced 
Fujita Scale.

The largest hail reported was grapefruit size at Millersview, where skylights were 
broken in homes. About 3 miles south of Melvin, wind-driven baseball size hail
caused extensive damage.  East-facing windows in homes were broken, and roofs on 
homes were damaged.  In addition, the corn crop was stripped in a nearby field.

Baseball size hail was also reported 6 miles west-southwest of the town of Mason, 
and golfball to baseball size was reported in Ballinger.  Large hail to tennis ball 
size was reported 11 miles north-northeast of Hext (Mcculloch County). Late in the 
evening, a couple of severe storms moved south-southeast into Haskell and 
Throckmorton Counties.  Hail to hen egg size hail was reported at Rochester (Haskell
County), and a 77 mph wind gust was recorded at a MESONET site one mile north-
northwest of the town of Haskell. 

In all, a total of 29 severe weather reports were received for this event.

Following a weak cold frontal passage, temperatures were slightly cooler on the 
31st, when highs were in the upper 80s to lower 90s.