WFO San Angelo Climatology

JANUARY 2011 WEATHER SUMMARY FOR WEST-CENTRAL TEXAS

...PRECIPITATION VARIED FROM MUCH ABOVE TO MUCH BELOW NORMAL IN
JANUARY...

THE MONTHLY AMOUNTS WERE OVER 2 INCHES ACROSS PARTS OF THE
SOUTHEASTERN BIG COUNTRY...NORTHEASTERN CONCHO VALLEY AND
HEARTLAND. LESS THAN ONE HALF INCH OCCURRED ACROSS PARTS OF
THE NORTHWESTERN BIG COUNTRY...NORTHWESTERN CONCHO VALLEY...
AND WESTERN CROCKETT COUNTY.  

TEMPERATURES AVERAGED NEAR NORMAL FOR THE MONTH.

AT ABILENE REGIONAL AIRPORT...THE AVERAGE TEMPERATURE FOR
JANUARY WAS 42.7 DEGREES. THIS WAS 0.8 DEGREES BELOW THE
NORMAL AVERAGE TEMPERATURE OF 43.5 DEGREES. TOTAL
PRECIPITATION FOR JANUARY WAS 0.92 INCHES. THIS WAS 0.05
INCHES BELOW THE MONTHLY NORMAL OF 0.97 INCHES. A TRACE OF
SNOWFALL WAS RECORDED IN ABILENE IN JANUARY.

AT SAN ANGELO REGIONAL AIRPORT...THE AVERAGE TEMPERATURE
FOR JANUARY WAS 45.8 DEGREES. THIS WAS 0.9 DEGREES ABOVE
THE NORMAL AVERAGE TEMPERATURE OF 44.9 DEGREES. TOTAL
PRECIPITATION FOR JANUARY WAS 0.68 INCHES. THIS WAS 0.14
INCHES BELOW THE MONTHLY NORMAL OF 0.82 INCHES. NO SNOWFALL
WAS RECORDED IN SAN ANGELO IN JANUARY. 

JANUARY 2011 WEATHER HIGHLIGHTS...

A DRY AND TRANQUIL WEATHER PATTERN OCCURRED DURING THE FIRST
WEEK OF JANUARY.

A RAIN EVENT OCCURRED ON THE 8TH AND 9TH...AS A STRONG UPPER
LEVEL DISTURBANCE MOVED NORTHEAST ACROSS THE REGION. SHOWERS
AND SCATTERED THUNDERSTORMS DEVELOPED ON THE EVENING OF THE 9TH
AND QUICKLY BECAME MORE WIDESPREAD ACROSS ROUGHLY THE
SOUTHEASTERN HALF OF WEST CENTRAL TEXAS. THE HEAVIEST RAINFALL
AMOUNTS OVER 1.5 INCHES OCCURRED IN SCATTERED POCKETS ACROSS
THE HEARTLAND. AMOUNTS BETWEEN ONE HALF INCH AND 1.5 INCHES
OCCURRED ACROSS MUCH OF THE AREA SOUTHEAST OF A LINE FROM
SONORA TO COLEMAN TO LAKE BROWNWOOD. THESE AMOUNTS ALSO
OCCURRED ACROSS NORTHERN CROCKETT AND EASTERN RUNNELS COUNTIES.
ELSEWHERE THE AMOUNTS VARIED UNDER ONE HALF INCH.

FOLLOWING A STRONG COLD FRONTAL PASSAGE ON THE 10TH...A MUCH
COLDER AIRMASS SETTLED INTO THE REGION ON THE 11TH AND 12TH.
ON THE 11TH...LOW TEMPERATURES WERE IN THE TEENS TO LOWER 20S...
HIGHS RANGED FROM THE 30S ACROSS THE NORTHEASTERN HALF OF WEST
CENTRAL TEXAS...TO THE LOWER 40S IN THE SOUTHWESTERN HALF. ON
THE 12TH...LOWS WERE IN THE TEENS AND 20S WHILE HIGHS WERE
MOSTLY IN THE 30S ACROSS THE AREA.

A CHANGEABLE WEATHER PATTERN AFFECTED THE REGION DURING THE
MIDDLE OF THE MONTH.

WITH AN INCREASE IN MOISTURE ACROSS THE REGION...AREAS OF FOG
OCCURRED ON THE 15TH AND 16TH...ALONG WITH PATCHY DRIZZLE AND
LIGHT RAIN. THIS WAS IN ASSOCIATION WITH AN UPPER LEVEL
DISTURBANCE WHICH TRACKED ACROSS NORTHEASTERN MEXICO AND DEEP
SOUTH TEXAS. VISIBILITY IN THE FOG OCCASIONALLY DROPPED BELOW
ONE HALF MILE AT NUMEROUS LOCATIONS. PATCHY LIGHT RAIN OCCURRED
ACROSS THE AREA SOUTHEAST OF A LINE FROM SONORA TO BROWNWOOD...
AND THE AMOUNTS WERE MOSTLY LESS THAN ONE TENTH OF AN INCH.

DRIER AIR OVERSPREAD THE REGION ON THE 17TH AND WAS ACCOMPANIED
BY CLEARING SKIES...SOMEWHAT GUSTY SOUTH TO SOUTHWEST WINDS...AND
MUCH WARMER TEMPERATURES. HIGHS ON THE 17TH RANGED FROM THE MID
60S TO MID 70S...WITH 77 DEGREES RECORDED AT ROBERT LEE AND SAN
ANGELO. A WEAK COLD FRONTAL PASSAGE BROUGHT COOLER AIR ON THE
18TH...MAINLY TO THE BIG COUNTRY. A QUICK WARMUP OCCURRED AGAIN
ON THE 19TH WITH GUSTY SOUTH WINDS.

A STRONG COLD FRONT SURGED THROUGH THE REGION ON THE MORNING OF
THE 20TH. THIS BROUGHT A BRIEF INTRUSION OF COLDER AIR INTO THE
REGION. LOW TEMPERATURES ON THE EARLY MORNING OF THE 21ST WERE
MOSTLY IN THE TEENS ACROSS WEST CENTRAL TEXAS. 

THE LATE PART OF THE MONTH WAS DRY WITH A FEW COLD FRONTAL
PASSAGES. HIGH TEMPERATURES WERE WELL-ABOVE NORMAL AREAWIDE ON
THE 28TH AND 29TH...AND ACROSS THE REGION SOUTH OF INTERSTATE
20 ON THE 30TH AND 31ST. THE WARMEST TEMPERATURES FOR THE MONTH 
OCCURRED DURING THIS TIME WHEN HIGHS WERE IN THE 70S ACROSS MOST
OF THE AREA. A STATION NEAR BROWNWOOD RECORDED A HIGH OF 83
DEGREES ON THE 29TH...AND SAN ANGELO RECORDED HIGHS OF 80
DEGREES ON THE 29TH AND 31ST.

A MAJOR WEATHER EVENT OCCURRED FROM THE EVENING OF THE 31ST INTO
THE POST-MIDNIGHT HOURS OF FEBRUARY 1ST. A WARM AIRMASS WAS
SITUATED OVER THE REGION ON THE 31ST...AND AFTERNOON HIGH
TEMPERATURES WERE IN THE 70S ACROSS MUCH OF WEST CENTRAL TEXAS.
AN ARCTIC COLD FRONT SWEPT SOUTH ACROSS THE BIG COUNTRY DURING
THE EVENING...AND REACHED THE INTERSTATE 10 CORRIDOR SHORTLY
AFTER MIDNIGHT. AT THE SAME TIME...A POTENT UPPER LEVEL STORM
SYSTEM APPROACHED THE REGION FROM THE WEST. WITH THE APPROACH
OF THIS SYSTEM...SHOWERS AND THUNDERSTORMS DEVELOPED DURING THE
EVENING AND BECAME NUMEROUS IN THE HOURS BEFORE MIDNIGHT. A
NUMBER OF THE STORMS PRODUCED SMALL HAIL. THE LARGEST HAIL SIZE
REPORTED WAS NICKEL SIZE...IN SAN ANGELO AND 3 MILES EAST OF
ROBERT LEE. GUSTY NORTH WINDS ALSO ACCOMPANIED THE STORMS. PEAK
WIND GUSTS REACHED 44 MPH AT SAN ANGELO AND 43 MPH AT ABILENE.
AS MUCH COLDER AIR RAPIDLY INVADED THE AREA BEHIND THE STRONG
COLD FRONT...THE PRECIPTATION QUICKLY CHANGED TO SLEET AND SNOW
ACROSS THE BIG COUNTRY AND INTO THE CONCHO VALLEY AND HEARTLAND
BEFORE MIDNIGHT. IN ADDITION...THE WINTER PRECIPITATION WAS
ACCOMPANIED BY LIGHTNING AND THUNDER...AND BEGAN TO ACCUMULATE
BEFORE MIDNIGHT ACROSS THE BIG COUNTRY.

$$