Climate Summary for December 2011

December 2011 Weather Highlights for West-Central Texas

...Temperatures averaged below normal across West Central Texas in December...

Precipitation for the month varied from slightly below normal to well-above normal.
The monthly precipitation amounts were well-above normal across much of the 
southeastern part of west-central Texas, and across the northwestern Big country.
The monthly amounts were slightly below normal across parts of the eastern Big 
Country, parts of the northern and western Concho Valley, and parts of Crockett 
County.  Elsewhere, precipitation for the month was near to slightly above normal.  

At Abilene Regional Airport, the average temperature for December was 44.1 degrees.  
This was 1.2 degrees below the normal average temperature of 45.3 degrees.  Total 
precipitation for Abilene in November was 1.93 inches.  This was 0.70 inches above
the normal of 1.23 inches.  

At San Angelo Regional Airport, the average temperature for December was 46.3 degrees.
This was 0.4 degrees below the normal average temperature of 46.7 degrees.  Total 
precipitation for San Angelo was 0.98 inches.  This was 0.13 inches above the normal 
of 0.85 inches. 

Total snowfall for December was 1.3 inches at Abilene, and a trace at San Angelo.

Weather Highlights for December 2011...

With warm and dry conditions on the 1st, high temperatures were in the upper 60s to
lower 70s across central and southern sections of west-central Texas. 

Unsettled weather patterns were prevalent until the last week of December.  This 
resulted in many days with cloudy skies, precipitation, and below normal temperatures. During this
time, several upper level storm systems approached the region from the Southwestern
states and interacted with moist air. This time frame was also marked by several 
strong cold frontal passages.

The heavier rainfall with more widespread coverage occurred across much of the 
southeastern half of west-central Texas.  From the 1st through the 17th, total
precipitation amounts ranged from one half inch to more than 3 inches...to the 
southeast of a line from Ozona to San Angelo to Baird.  A band of 1-3 inch 
precipitation amounts also occurred across the northern and western Big Country, 
northwest of a line from Throckmorton to Anson to Maryneal.  Lesser precipitation
totals occurred across the remainder of west-central Texas.   
 
A winter weather event occurred early in the month, when snow fell across the Big
Country and parts of the Concho Valley and northern Heartland on the 5th.  Across the
Big Country, the snowfall amounts were mostly in the range of 1-2 inches. The heaviest
amounts (3 inches or slightly more) occurred along the Interstate 20 corridor. In
Abilene, the official snowfall was 1.3 inches.  Farther south across Sterling, Coke,
Coleman, northern Tom Green, and northern Concho Counties, the amounts ranged from a
trace to one inch.

The coldest temperatures for the month occurred on the 5th and 6th. Daytime readings 
were in the 30s on the 5th, and highs on the 6th ranged from the upper 20s across
parts of the Big Country, to the mid to upper 30s across southern sections of west-
central Texas. As a cold high pressure system settled south across the area, clear
skies and light winds allowed temperatures to dip into the teens to lower 20s. A 
record low temperature of 21 degrees was set at San Angelo on the 7th.

Gusty south to southwest winds occurred on the 19th.  Peak wind gusts reached 43 mph
at Abilene, and 40 mph at San Angelo.

Light snow occurred across the Big Country and parts of the northern Concho Valley
on the morning of the 24th. Snowfall accumulations were generally an inch or less.
Farther to the south, light rain was mixed at times with light snow at San Angelo.
Patchy light mixed precipitation continued into the post-Midnight hours of the 25th.

Skies cleared across west-central Texas on the 26th, as drier air moved into the area
with west winds.

With a significant change to a drier weather pattern during the final week of the
month (27-31), skies were mostly clear across the region with a larger daily range 
between the early morning low temperatures and afternoon high temperatures.  A warming 
trend in the daytime temperatures occurred during this time frame. The warmest day for
the month was on the 31st, when highs reached the upper 70s to lower 80s.   

Following a strong cold frontal passage on New Year's Eve (31st), a north wind gust 
of 40 mph was recorded at Abilene.