WFO San Angelo Climatology

...WEST CENTRAL TEXAS WEATHER SUMMARY FOR 2010...

TOTAL PRECIPITATION FOR THE YEAR VARIED FROM ABOVE TO BELOW
NORMAL ACROSS WEST CENTRAL TEXAS. THE PRECIPITATION WAS NOT
EVENLY DISTRIBUTED OVER TIME. OVERALL...MUCH OF THE ANNUAL
PRECIPITATION OCCURRED FROM JANUARY THROUGH AUGUST. THE
ABOVE NORMAL YEARLY PRECIPITATION OCCURRED ACROSS AREAS OF
THE BIG COUNTRY...NORTHERN AND EASTERN CONCHO VALLEY...AND
IN PARTS OF THE SOUTHERN HEARTLAND INTO MASON COUNTY.

AT ABILENE REGIONAL AIRPORT...THE ANNUAL AVERAGE TEMPERATURE
FOR 2010 WAS 64.9 DEGREES. THIS WAS 0.5 DEGREES ABOVE THE
NORMAL AVERAGE TEMPERATURE OF 64.4 DEGREES. TOTAL
PRECIPITATION FOR THE YEAR WAS 27.79 INCHES. THIS WAS 4.01
INCHES ABOVE THE NORMAL ANNUAL PRECIPITATION OF 23.78
INCHES. TOTAL SNOWFALL FOR THE YEAR AT ABILENE WAS 7.0
INCHES. THIS WAS 2.1 INCHES ABOVE THE NORMAL YEARLY
SNOWFALL OF 4.9 INCHES.

AT SAN ANGELO REGIONAL AIRPORT...THE ANNUAL AVERAGE
TEMPERATURE FOR 2010 WAS 66.6 DEGREES. THIS WAS 2.1 DEGREES
ABOVE THE NORMAL ANNUAL AVERAGE TEMPERATURE OF 64.5 DEGREES.
TOTAL PRECIPITATION FOR THE YEAR WAS 20.13 INCHES. THIS WAS
0.78 INCHES BELOW THE NORMAL ANNUAL PRECIPITATION OF 20.91
INCHES. TOTAL SNOWFALL FOR THE YEAR AT SAN ANGELO WAS 4.0
INCHES. THIS WAS 1.1 INCHES ABOVE THE NORMAL YEARLY
SNOWFALL OF 2.9 INCHES.

THE ANNUAL TOTAL NUMBER OF DAYS WHERE HIGH TEMPERATURES
REACHED OR EXCEEDED 100 DEGREES INCLUDE 42 AT SAN ANGELO...
WHICH SETS THE 4TH PLACE RANK FOR THE GREATEST ANNUAL
NUMBER OF DAYS WITH HIGH TEMPERATURES OF 100 OR MORE.

ABILENE RECORDED AN ANNUAL TOTAL OF 11 DAYS...AND JUNCTION
RECORDED A TOTAL OF 18 DAYS...WHERE HIGH TEMPERATURES
REACHED OR EXCEEDED 100 DEGREES.

SAN ANGELO RECORDED A YEARLY TOTAL OF 3 DAYS WITH LOW
TEMPERATURES OF 80 DEGREES OR WARMER. ONLY 2 PREVIOUS YEARS
IN THE SAN ANGELO CLIMATE RECORD HAD A TOTAL OF 3 DAYS
WITH LOW TEMPERATURES OF 80 DEGREES OR MORE.

ONE OF THE MAIN INFLUENCES ON THE REGIONAL WEATHER PATTERNS
DURING THE YEAR WAS BROUGHT ABOUT BY A SIGNIFICANT
TRANSITION IN THE WATERS OF THE EQUATORIAL PACIFIC OCEAN.
WITH A WARMING OF THESE WATERS...EL NINO CONDITIONS
OCCURRED DURING THE WINTER AND EARLY SPRING. THE EL NINO
CONDITIONS WEAKENED BY LATE SPRING...AND A TRANSITION TO
NEUTRAL CONDITIONS WAS UNDERWAY BY THE BEGINNING OF SUMMER.
THIS WAS BROUGHT ABOUT BY COOLING OF THE WATERS IN THE
EQUATORIAL PACIFIC. THE COOLING INTENSIFIED AND EXPANDED
ACROSS MUCH OF THE EQUATORIAL PACIFIC OCEAN. THIS LED TO
A QUICK TRANSITION TO LA NINA CONDITIONS BY THE END OF
SUMMER. LA NINA CONDITIONS STRENGTHENED DURING THE AUTUMN
SEASON AND REMAINED STRONG THROUGH THE END OF THE YEAR.

* WINTER WEATHER *

WITH EL NINO CONDITIONS DURING THE WINTER MONTHS OF JANUARY
AND FEBRUARY...A NUMBER OF PRECIPITATION EVENTS OCCURRED
ACROSS THE REGION...AND SOME OF THESE WERE IN THE FORM OF
SNOW.  PRECIPITATION WAS ABOVE NORMAL DURING THIS TIME...
AND ABILENE RECORDED ITS 4TH WETTEST JANUARY. 

A STORM SYSTEM IN LATE JANUARY (JANUARY 28TH) BROUGHT SHOWERS
AND THUNDERSTORMS WITH HEAVY RAINFALL AND LOCALLY STRONG GUSTY
WINDS. WIDESPREAD WIND DAMAGE WAS REPORTED IN THE TOWN OF
COLEMAN. SOME WIND DAMAGE WAS ALSO REPORTED 15 MILES WEST OF
STERLING CITY...AND A ROOF WAS BLOWN OFF OF A MOTEL IN CROSS
PLAINS. THE HEAVIEST RAINFALL AMOUNTS OF 3 TO 5 INCHES OCCURRED
AT SCATTERED LOCATIONS IN EASTERN SECTIONS OF WEST CENTRAL
TEXAS. AMOUNTS OF 1 TO 3 INCHES WERE COMMON ACROSS THE REST OF
THE AREA EAST OF A LINE FROM OZONA TO SAN ANGELO TO ABILENE.
THE HEAVY RAIN CAUSED STREET FLOODING IN HAMBY (JONES COUNTY).

THE MAIN WINTER PRECIPITATION EVENTS OCCURRED IN FEBRUARY. WITH
THE ARRIVAL OF A POTENT UPPER LEVEL DISTURBANCE ON FEBRUARY
11TH...HEAVY SNOWFALL OF 4 TO 8 INCHES OCCURRED ACROSS MUCH OF
THE BIG COUNTRY NORTHEAST OF A LINE FROM ROBY TO BAIRD. ABILENE
RECORDED 3 INCHES. LIGHTER SNOWFALL OCCURRED FARTHER SOUTH INTO
THE NORTHERN CONCHO VALLEY AND NORTHERN HEARTLAND WITH AMOUNTS
MOSTLY AN INCH OR LESS. SOME SLEET OCCURRED ACROSS COLEMAN AND
BROWN COUNTIES.

ON FEBRUARY 23RD...AN UPPER LEVEL STORM SYSTEM BROUGHT SNOW TO
WEST CENTRAL TEXAS. THE HEAVIEST SNOWFALL OF 4 TO 6 INCHES
OCCURRED ACROSS THE SOUTHERN BIG COUNTRY...CONCHO VALLEY AND
HEARTLAND. AMOUNTS OF 2 TO 4 INCHES OCCURRED FARTHER NORTH INTO
THE BIG COUNTRY...AND FARTHER TO THE SOUTH ACROSS PARTS OF THE
NORTHERN EDWARDS PLATEAU AND NORTHWEST HILL COUNTRY. MOST AREAS
SOUTH OF INTERSTATE 10 RECEIVED LESS THAN 2 INCHES.

THE COLDEST TEMPERATURES FOR THE YEAR OCCURRED IN EARLY JANUARY.
FOLLOWING AN ARCTIC COLD FRONTAL PASSAGE...TEMPERATURES DROPPED
INTO THE UPPER TEENS TO LOWER 20S ACROSS THE NORTHERN HALF OF
WEST CENTRAL TEXAS...AND WERE ACCOMPANIED BY GUSTY NORTH WINDS.
THIS CREATED WIND CHILL VALUES NEAR OR BELOW ZERO AT SOME
LOCATIONS...ESPECIALLY ACROSS THE BIG COUNTRY. THE COLDEST
TEMPERATURES OCCURRED WITH THE LOWS ON THE EARLY MORNING OF
THE 9TH...AS A STRONG HIGH PRESSURE SYSTEM DEVELOPED SOUTH INTO
TEXAS. LOWS ON THE 9TH WERE IN THE 5 TO 15 DEGREE RANGE...AND A
RECORD LOW TEMPERATURE WAS SET AT SAN ANGELO.

 
* SPRING AND SEVERE WEATHER *

DURING THE SPRING...PRECIPITATION BECAME MORE VARIABLE...BUT A
NUMBER OF WET EVENTS OCCURRED. OF NOTE WAS THE UNUSUAL LACK OF
SEVERE WEATHER DURING MUCH OF THIS SEASON (UNTIL THE MIDDLE OF
MAY). DURING THE PRECEEDING WINTER SEASON...ON A NUMBER OF
OCCASIONS...COLD AND DRY AIRMASSES PLUNGED SOUTHWARD WELL INTO
THE GULF OF MEXICO. THIS AFFECTED A LARGE ENOUGH AREA TO REQUIRE
AN EXTENSIVE PERIOD OF TIME FOR GULF MOISTURE TO RECOVER TO
TYPICAL LEVELS. AS A RESULT...THE DISTURBANCES AND FRONTAL
SYSTEMS WHICH MOVED INTO WEST CENTRAL TEXAS INTERACTED WITH
MOISTURE AND INSTABILITY WHICH WAS OFTEN TOO LIMITED...TO
SUPPORT SEVERE THUNDERSTORMS.  

THE MAIN SEVERE WEATHER EVENTS OCCURRED IN MAY AND THE FIRST
HALF OF JUNE. ON MAY 14TH...SEVERAL STRONG TO SEVERE STORMS
OCCURRED ACROSS THE CONCHO VALLEY...AND PING-PONG SIZE HAIL
WAS REPORTED 2 MILES NORTH OF ORIENT (TOM GREEN COUNTY).
BEHIND THE STORMS...STRONG EAST WINDS DEVELOPED OVER THE CONCHO
VALLEY...AND A PEAK WIND GUST OF 58 MPH WAS RECORDED AT SAN
ANGELO. ON MAY 15TH...A SEVERE STORM PRODUCED WIND DAMAGE
AND NICKEL SIZE HAIL IN MASON...AND A FUNNEL CLOUD WAS REPORTED
15 MILES NORTHWEST OF MASON. 

A SEVERE WEATHER EVENT WITH STRONG WINDS OCCURRED ON MAY 17TH.
PEAK WIND GUSTS REACHED 64 MPH AT ABILENE REGIONAL AIRPORT...60
MPH AT DYESS AIR FORCE BASE...AND 52 MPH AT JUNCTION. A COUPLE
OF REPORTS OF WIND DAMAGE TO TREES WERE RECEIVED FROM THE BIG
COUNTRY. IN TOM GREEN COUNTY...WIND DAMAGE OCCURRED AT GRAPE
CREEK...IN THE TOWN OF WALL...AND 12 MILES EAST OF SAN ANGELO.

A FLOODING EVENT OCCURRED IN MASON COUNTY IN LATE MAY. VERY
HEAVY RAINFALL OF 4 TO 7 INCHES CAUSED FLASH FLOODING OF
STREETS IN THE TOWN OF MASON...AND NECESSITATED THE CLOSURE OF
OTHER ROADS IN MASON COUNTY. IN ADDITION...A COUPLE OF HIGH
WATER RESCUES WERE REPORTED. IN MCCULLOCH COUNTY A BRIDGE WAS
DAMAGED AND IMPASSABLE 4 MILES SOUTH-SOUTHWEST OF VOCA...ALONG
COUNTY ROAD 216.

VERY HEAVY RAINFALL ALSO OCCURRED ACROSS PARTS OF NORTHERN
EDWARDS COUNTY...IN THE UPPER PART OF THE DRAINAGE BASIN OF THE
SOUTH LLANO RIVER. LOCALIZED RAINFALL AMOUNTS RANGED FROM 6 TO
10 INCHES ACROSS THAT AREA. THIS LED TO RAPID WATER RISES ALONG
THE SOUTH LLANO RIVER ON THE MORNING OF THE 25TH. AT TELEGRAPH
(KIMBLE COUNTY)...THE WATER LEVEL ROSE 15 FEET IN A 2-HOUR TIME
PERIOD. A LOW WATER CROSSING 7 MILES SOUTH OF JUNCTION WAS ALSO
FLOODED. THE LLANO RIVER NEAR MASON ROSE ABOVE BANKFULL ON THE
MORNING OF THE 26TH.

A SEVERE WEATHER AND HEAVY RAIN EVENT OCCURRED ON JUNE 2ND.
SOFTBALL SIZE HAIL WAS REPORTED AT EDEN (CONCHO COUNTY)...AND
HEN EGG TO BASEBALL SIZE HAIL WAS REPORTED NEAR CHEROKEE (SAN
SABA COUNTY). GOLFBALL SIZE HAIL OCCURRED AT WINCHELL (BROWN
COUNTY). STRONG THUNDERSTORM WINDS DOWNED NUMEROUS TREE LIMBS
IN MENARD...AND DAMAGED A SECTION OF ROOF AT ONE OF THE ABILENE
FIRE STATIONS. TREE LIMBS WERE BLOWN DOWN AT THE KHOS STUDIO IN
SONORA. HEAVY RAINFALL FROM THE STORMS FLOODED LOW WATER
CROSSINGS IN BRADY...AND HIGH WATER WAS REPORTED OVER FARM
ROAD 504 BETWEEN PEAR VALLEY AND LOHN (MCCULLOCH COUNTY).  A
TOTAL OF 25 SEVERE WEATHER AND FLASH FLOODING REPORTS WERE
RECEIVED FOR THIS EVENT.

SEVERAL CLUSTERS OF THUNDERSTORMS MOVED SOUTHEAST ACROSS THE
BIG COUNTRY AND INTO THE NORTHERN HEARTLAND...FROM THE LATE
EVENING OF JUNE 15TH INTO THE MORNING OF THE 15TH. A 71 MPH
WIND GUST WAS MEASURED 1 MILE NORTHWEST OF HASKELL...FROM A
SEVERE STORM IN THAT AREA. VERY HEAVY RAINFALL ACCOMPANIED
THE STORMS...AND A NEW DAILY RECORD RAINFALL AMOUNT WAS
RECORDED IN ABILENE ON JUNE 15TH.

* SUMMER WEATHER *

THE 2ND WARMEST SUMMER ON RECORD WAS TIED AT SAN ANGELO...
FOR THE MONTHS OF JUNE...JULY AND AUGUST. 

IN JUNE...AN UPPER LEVEL HIGH PRESSURE SYSTEM DOMINATED THE
WEATHER PATTERN AT TIMES...BUT OTHER WEATHER SYSTEMS ALSO HAD
AN INFLUENCE. WITH A SEVERE WEATHER AND HEAVY RAIN EVENT ON
JUNE 2ND...A TOTAL OF 25 SEVERE WEATHER AND FLASH FLOODING
REPORTS WERE RECEIVED. THUNDERSTORMS AND HEAVY RAINFALL ALSO
AFFECTED THE REGION DURING THE MIDDLE OF THE MONTH...AND A
RELATIVELY WET PERIOD DEVELOPED DURING THE LAST WEEK OFJUNE.

TEMPERATURES WERE VERY HOT ON SOME OCCASIONS...AND THE AIRMASS
WAS HUMID ACROSS THE REGION AT TIMES. THE COMBINATION OF HEAT
AND HUMIDITY RESULTED IN ELEVATED HEAT INDEX VALUES ON A FEW
DAYS. SAN ANGELO TIED ITS 5TH WARMEST JUNE. A RECORD HIGH
TEMPERATURE WAS SET AT SAN ANGELO ON JUNE 5TH. IN ADDITION...
SEVERAL RECORD HIGH MINIMUM TEMPERATURES WERE SET OR EQUALED
AT SAN ANGELO AND ABILENE DURING JUNE.

IN JULY...AN UPPER LEVEL HIGH PRESSURE SYSTEM DOMINATED THE
WEATHER PATTERN PRIMARILY DURING THE MIDDLE OF THE MONTH AND
DURING THE LAST FEW DAYS OF THE MONTH. A COOLER AND WETTER
PATTERN...WHICH DEVELOPED DURING THE LAST WEEK IN JUNE...
CONTINUED DURING THE FIRST PART OF JULY IN WEST CENTRAL TEXAS.
FOR JULY 1-10...RAINFALL AMOUNTS OF 2 TO 4 INCHES WERE
WIDESPREAD ACROSS WEST CENTRAL TEXAS. WIDELY SCATTERED
LOCATIONS RECEIVED MORE THAN 5 INCHES. ABILENE RECORDED ITS
7TH WETTEST JULY. A RECORD LOW MAXIMUM TEMPERATURE WAS SET AT
SAN ANGELO ON THE 1ST. 

DURING MOST OF AUGUST...A LARGE AND STRONG UPPER LEVEL HIGH
PRESSURE SYSTEM WAS SITUATED OVER TEXAS AND MUCH OF THE
SOUTHERN UNITED STATES. THIS RESULTED IN A PERSISTENTLY HOT
AND DRY PATTERN FOR WEST CENTRAL TEXAS. DAILY HIGH
TEMPERATURES REACHED OR EXCEEDED 100 DEGREES ACROSS MOST OF
WEST CENTRAL TEXAS WITH THIS PATTERN. NIGHTTIME TEMPERATURES
WERE ALSO WARMER THAN NORMAL.

SAN ANGELO TIED ITS 2ND WARMEST AUGUST ON RECORD...AND
ABILENE TIED ITS 10TH WARMEST AUGUST. A NUMBER OF HIGH
TEMPERATURE AND WARMEST MINIMUM TEMPERATURE RECORDS WERE SET
OR TIED AT ABILENE AND SAN ANGELO IN AUGUST.

IN ADDITION...SAN ANGELO RECORDED 3 DAYS WITH LOW
TEMPERATURES AT OR ABOVE 80 DEGREES DURING AUGUST. THE
OCCURRENCE OF LOW TEMPERATURES OF 80 DEGREES OR MORE IS
RELATIVELY RARE IN WEST CENTRAL TEXAS. ON AUGUST 8TH...THE
LOW TEMPERATURE OF 81 AT SAN ANGELO NOT ONLY SET A NEW
RECORD WARM LOW FOR THAT DATE...BUT ALSO TIED FOR THE ALL-
TIME WARMEST LOW TEMPERATURE ON RECORD. THIS RECORD WARM
LOW WAS ALSO PREVIOUSLY SET ON THREE OTHER DATES IN SAN
ANGELO. THE RECORD WARM MINUMUM TEMPERATURE RECORDS FOR SAN
ANGELO (AND ABILENE) EXTEND BACK TO 1951.

DURING MUCH OF SEPTEMBER...AN UPPER LEVEL HIGH PRESSURE
SYSTEM WAS POSITIONED OVER TEXAS AND THE SURROUNDING REGION.
HOT AND DRY CONDITIONS ACCOMPANIED THIS PATTERN. RECORD
HIGH MINIMUM TEMPERATURES WERE SET AT ABILENE AND SAN
ANGELO ON SEPTEMBER 10TH. RECORD HIGH MINIMUM TEMPERATURES
WERE TIED AT ABILENE ON SEPTEMBER 1ST...AND AT SAN ANGELO
ON SEPTEMBER 12TH...15TH...AND 24TH.

WET WEATHER OCCURRED ON A FEW OCCASIONS DURING SEPTEMBER.
THE REMNANTS OF TROPICAL STORM HERMINE TRACKED NORTH ACROSS
EASTERN PARTS OF WEST CENTRAL TEXAS ON SEPTEMBER 7TH AND
8TH. HEAVY RAIN ACCOMPANIED THIS SYSTEM. MUCH OF THE AREA
EAST OF A LINE FROM ALBANY TO MASON RECEIVED BETWEEN 2.5
AND 5 INCHES OF RAINFALL. HOWEVER...THE RAINFALL OCCURRED
OVER A LONG ENOUGH PERIOD OF TIME TO MINIMIZE FLOODING.

* AUTUMN WEATHER *

TEMPERATURES AVERAGED ABOVE NORMAL IN SEPTEMBER...OCTOBER
AND NOVEMBER.

IN LATE SEPTEMBER...HEAVY RAIN AND SOME FLOODING OCCURRED
ON THE 25TH. THE HEAVY RAIN WAS MAINLY ACROSS THE NORTHERN
HALF OF WEST CENTRAL TEXAS. THE HEAVIEST RAINFALL OF 8 TO
10 INCHES ACROSS PARTS OF HASKELL AND THROCKMORTON COUNTIES
CAUSED FLOODING OF FARM FIELDS...AND FLOODING ACROSS A PART
OF HIGHWAY 380. ELSEWHERE...SOME LOCATIONS ACROSS THE BIG
COUNTRY AND CONCHO VALLEY RECEIVED 3 TO 6 INCHES OF RAIN
FROM THIS EVENT.

IN OCTOBER...HIGH PRESSURE SYSTEMS WERE OVER THE REGION
DURING MOST OF THE MONTH. THE AIRMASSES WERE DRY WITH A
LACK OF CLOUD COVER. THE DAILY HIGH TEMPERATURES WERE ABOVE
NORMAL...ESPECIALLY ACROSS CENTRAL AND SOUTHERN PARTS OF
WEST CENTRAL TEXAS. THE NUMBER OF DAYS WHERE HIGH
TEMPERATURES REACHED 88 DEGREES OR MORE INCLUDED...
11 AT SAN ANGELO
6 AT JUNCTION
ZERO AT ABILENE (HIGHEST TEMPERATURE WAS 87)

ALMOST ALL OF THE PRECIPITATION FOR OCTOBER OCCURRED WITH
A HEAVY EVENT LATE IN THE MONTH...ON OCTOBER 23RD. IN
SAN ANGELO...A NEW DAILY RECORD RAINFALL WAS SET...AND
THE HEAVY RAIN CAUSED FLASH FLOODING OF SEVERAL STREETS.  
WITH THIS EVENT...RAINFALL AMOUNTS OF 2 TO 3 INCHES
OCCURRED ACROSS MUCH OF THE AREA NORTHWEST OF A LINE FROM
CROSS PLAINS TO SAN ANGELO TO OZONA.

AFTER A COLD FRONTAL PASSAGE ON OCTOBER 27TH...SCATTERED
FROST OCCURRED ON THE EARLY MORNING OF THE 29TH...WITH A
LIGHT FREEZE AT SOME LOCATIONS. A NEW RECORD HIGH
TEMPERATURE WAS SET AT SAN ANGELO ON OCTOBER 31ST.

A RATHER DRY PATTERN PREVAILED DURING NOVEMBER...AS THE
REGIONAL WEATHER WAS INFLUENCED BY A NUMBER OF HIGH
PRESSURE SYSTEMS. A FEW UPPER LEVEL DISTURBANCES AND
SEVERAL COLD FRONTS MOVED ACROSS THE REGION...BUT WITH A
LACK OF MOISTURE...THESE SYSTEMS WERE PREDOMINANTLY DRY
FOR WEST CENTRAL TEXAS. THE PRECIPITATION EVENTS WERE
LIGHT...AND WERE CONFINED TO A FEW DAYS IN THE EARLY AND
MIDDLE PARTS OF NOVEMBER.

WITH THE DRY AIRMASS WHICH OCCUPIED THE REGION DURING
NOVEMBER...LARGE TEMPERATURE SWINGS OCCURRED ON A FEW
DAYS...BETWEEN THE DAYTIME HIGH TEMPERATURES AND NIGHTTIME
LOWS (40 DEGREES OR MORE AT SOME LOCATIONS).

THE RATHER DRY WEATHER PATTERN PREVAILED WELL INTO
DECEMBER. SEVERAL PERIODS OF ABOVE NORMAL TEMPERATURES
WERE INTERSPERSED WITH FAIRLY STRONG BUT DRY COLD FRONTAL
PASSAGES. THE COLD FRONTS BROUGHT INTRUSIONS OF COLDER AIR
WHICH LINGERED OVER THE REGION FOR A COUPLE OF DAYS AFTER
EACH FRONTAL PASSAGE. NEW RECORD HIGH TEMPERATURES WERE
SET AT ABILENE AND SAN ANGELO ON A FEW DAYS BETWEEN THE
15TH AND 21ST...WHEN TEMPERATURES SOARED INTO THE 80S FOR
HIGHS.

MOST OF THE DECEMBER PRECIPITATION OCCURRED WITH ONE RAIN
EVENT LATE IN THE MONTH...ON DECEMBER 24TH. 

$$