National Weather Service United States Department of Commerce

Powerful Storms to Impact the Western U.S. and Northern Plains

A strong, long-duration atmospheric river will bring excessive rainfall, flash flooding, and very strong winds to southwest Oregon and northwest California through Thursday. A High Risk (level 4 of 4) of Excessive Rainfall has been issued. A storm system over the northern Plains will produce locally heavy snow in North Dakota and northwestern Minnesota. Read More >

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SAN ANGELO TX
924 PM CDT WED MAY 6 2009

...7TH WETTEST APRIL ON RECORD AT SAN ANGELO...

...TEMPERATURES AVERAGED ABOVE NORMAL ACROSS WEST CENTRAL TEXAS
IN APRIL...

PRECIPITATION FOR THE MONTH VARIED FROM WELL ABOVE NORMAL TO
BELOW NORMAL. FOR MOST OF THE AREA NORTH OF A LINE FROM CROSS
CUT TO OH IVIE RESERVOIR TO ROBERT LEE...THE MONTHLY AMOUNTS
WERE BELOW NORMAL. FOR THE LARGE MAJORITY OF THE NORTHERN
EDWARDS PLATEAU...NORTHWEST HILL COUNTRY...AND NORTHWARD
ACROSS CONCHO...MCCULLOCH...AND SAN SABA COUNTIES...THE MONTHLY
PRECIPITATION WAS WELL ABOVE NORMAL. FOR SOME OF THESE AREAS...
APRIL PRECIPITATION TOTALS RANGED FROM 5 TO 8 INCHES.

AT ABILENE REGIONAL AIRPORT...THE AVERAGE TEMPERATURE FOR APRIL
WAS 65.8 DEGREES. THIS WAS 1.2 DEGREES ABOVE THE NORMAL AVERAGE
TEMPERATURE OF 64.6 DEGREES. THIS  TOTAL PRECIPITATION FOR APRIL
WAS 1.07 INCHES. THIS WAS 0.60 INCHES BELOW THE MONTHLY NORMAL OF
1.67 INCHES.

AT SAN ANGELO REGIONAL AIRPORT...THE AVERAGE TEMPERATURE FOR
APRIL WAS 66.6 DEGREES. THIS WAS 1.6 DEGREES ABOVE THE NORMAL
AVERAGE TEMPERATURE OF 65.0 DEGREES. TOTAL PRECIPITATION FOR
APRIL WAS 4.61 INCHES. THIS WAS 3.01 INCHES ABOVE THE MONTHLY
NORMAL OF 1.60 INCHES. THIS MARKS THE 7TH WETTEST APRIL ON
RECORD FOR SAN ANGELO.


APRIL 2009 WEATHER HIGHLIGHTS...

THE WEATHER PATTERN WAS ACTIVE DURING APRIL.

A POTENT UPPER LEVEL STORM SYSTEM BROUGHT STRONG GUSTY WINDS
TO WEST CENTRAL TEXAS ON THE 2ND. THIS SYSTEM DROPPED SOUTHEAST
TO THE RED RIVER VALLEY DURING THE POST-MIDNIGHT HOURS OF THE
2ND...THEN TRACKED EAST ACROSS FAR SOUTHERN OKLAHOMA. WITH THE
APPROACHO OF THIS SYSTEM...A BAND OF SHOWERS AND THUNDERSTORMS
DEVELOPED AND AFFECTED THE REGION SOUTHEAST OF A BROWNWOOD TO
CHRISTOVAL TO OZONA LINE. SCATTERED LOCATIONS RECEIVED ONE
QUARTER TO ONE HALF INCH RAINFALL AMOUNTS...AND A FEW LOCATIONS
RECEIVED MORE THAN ONE HALF INCH.  THE MOST SIGNIFICANT IMPACT
FROM THIS SYSTEM WAS THE STRONG GUSTY WEST TO NORTHWEST WINDS...
WHICH FOLLOWED A COLD FRONTAL PASSAGE. ACROSS NORTHERN AND
CENTRAL SECTIONS OF WEST CENTRAL TEXAS...WIND SPEEDS OF 30 TO
40 MPH OCCURRED WITH SOME GUSTS OVER 50 MPH. PEAK WIND GUSTS
INCLUDED 57 MPH AT ABILENE AND 58 MPH AT SAN ANGELO. THE WINDS
GRADUALLY SUBSIDED DURING THE AFTERNOON OF THE 2ND...AS THE
STORM SYSTEM MOVED AWAY FROM THE REGION.

A COLD FRONT MOVED THROUGH WEST CENTRAL TEXAS ON THE 5TH. IN
THE DAYS FOLLOWING THIS COLD FRONTAL PASSAGE...A STRONG HIGH
PRESSURE SYSTEM MOVED FROM CANADA DOWN ACROSS THE PLAINS STATES
AND INTO TEXAS. AFTER A VERY WARM DAY WITH HIGHS IN THE UPPER
80S TO LOWER 90S ON THE 4TH...TEMPERATURES WERE MUCH COOLER ON
THE 5TH AND 6TH. ON THE EARLY MORNING OF THE 7TH...CLEAR
SKIES...LIGHT WINDS AND STRONG RADIATIONAL COOLING ALLOWED
TEMPERATURES TO DIP INTO THE 20S FOR LOWS ACROSS WEST CENTRAL
TEXAS. A RECORD LOW OF 26 DEGREES WAS SET AT SAN ANGELO...AND A
RECORD LOW OF 28 DEGREES WAS TIED AT ABILENE.

WITH A COMBINATION OF A RATHER DRY AIRMASS...GUSTY SOUTH TO
SOUTHWEST WINDS AND CONSIDERABLE SUNSHINE...TEMPERATURES SOARED
INTO THE 90 TO 95 DEGREE RANGE FOR HIGHS ON THE 8TH. THIS WAS A
TEMPERATURE CHANGE 60 TO 70 DEGREES IN LESS THAN 48 HOURS.

ANOTHER STORM SYSTEM BROUGHT STRONG GUSTY WINDS...WARM AND VERY
DRY AIR AS IT MOVED EAST INTO THE SOUTHERN PLAINS AND THE RED
RIVER VALLEY ON THE 9TH. THE STRONGEST WINDS AFFECTED THE BIG
COUNTRY. PEAK WIND GUSTS INCLUDED 58 MPH AT ABILENE AND 52 MPH
AT SAN ANGELO. A COUPLE OF ADDITIONAL LOCATIONS IN THE BIG
COUNTRY (SWEETWATER AND 5 MILES NORTHWEST OF STAMFORD) ALSO
RECORDED WIND GUSTS BETWEEN 55 AND 60 MPH. RELATIVE HUMIDITY
VALUES DROPPED INTO THE RANGE OF 5-10 PERCENT ACROSS WEST
CENTRAL TEXAS. WITH THE COMBINATION OF WARM TEMPERATURES IN THE
80S...STRONG GUSTY WINDS AND VERY DRY AIR...SEVERAL GRASS FIRES
OCCURRED ACROSS THE REGION.

ANOTHER POTENT STORM SYSTEM MOVED ACROSS THE SOUTHWESTERN
STATES AND APPROACHED TEXAS WITH A TRACK FARTHER TO THE SOUTH
THAN THE PREVIOUS SYSTEMS. WITH A FRONTAL SYSTEM AND MOISTURE
IN THE REGION...A LARGE AREA OF THUNDERSTORMS MOVED EAST
ACROSS WEST CENTRAL TEXAS...FROM THE EARLY NIGHTTIME HOURS OF
THE 11TH INTO THE EARLY MORNING HOURS OF THE 12TH. A COUPLE OF
STORMS WERE SEVERE. GOLFBALL SIZE HAIL WAS REPORTED AT RULE
(HASKELL COUNTY)...AND NICKEL SIZE HAIL OCCURRED 8 MILES WEST
AND 5 MILES SOUTH OF ROBY (FISHER COUNTY). ABILENE RECORDED
A PEAK WIND GUST OF 47 MPH ON THE EVENING OF THE 11TH...WELL
BEFORE ANY OF THE THUNDERSTORMS APPROACHED FROM THE WEST AND
SOUTHWEST.

THE GREATEST RAINFALL AMOUNTS FOR THIS EVENT...IN THE RANGE OF
ONE HALF TO 1.5 INCHES...OCCURRED ACROSS THE NORTHERN AND
EASTERN BIG COUNTRY. ONE HALF TO ONE INCH AMOUNTS OCCURRED
ACROSS MUCH OF THE HEARTLAND...AND ACROSS AREAS OF THE CONCHO
VALLEY AND NORTHERN EDWARDS PLATEAU.  ELSEWHERE THE RAINFALL
AMOUNTS WERE GENERALLY BETWEEN ONE QUARTER AND ONE HALF INCH.

A LARGE AREA OF SHOWERS AND THUNDERSTORMS MOVED EAST ACROSS
WEST CENTRAL TEXAS FROM THE POST MIDNIGHT HOURS INTO THE
MORNING OF THE 17TH...AS AN UPPER LEVEL STORM SYSTEM
APPROACHED FROM NEW MEXICO. A SEVERE THUNDERSTORM PRODUCED
QUARTER SIZE HAIL AT CHEROKEE (SAN SABA COUNTY). HEAVY RAIN
CAUSED STREET FLOODING IN SONORA. FLOODING WAS ALSO REPORTED
ON HIGHWAY 202 JUST NORTHEAST OF SONORA. THE HEAVIEST RAINFALL
OCCURRED ACROSS THE HEARTLAND...NORTHWEST HILL COUNTRY AND
NORTHERN EDWARDS PLATEAU...WHERE AMOUNTS BETWEEN 1 AND 2.5
INCHES WERE COMMON. FARTHER TO THE NORTH ACROSS THE CONCHO
VALLEY AND BIG COUNTRY...SCATTERED LOCATIONS RECEIVED
RAINFALL AMOUNTS IN THE RANGE OF ONE HALF TO 1.5 INCHES.

A NARROW NORTH TO SOUTH BAND OF SHOWERS AND THUNDERSTORMS
OCCURRED OVER THE WESTERN BIG COUNTRY AND NORTHERN CONCHO
VALLEY ON THE EVENING OF THE 17TH...IN THE VICINITY OF A
DRYLINE. RAINFALL AMOUNTS VARIED UNDER ONE HALF INCH.

HOT TEMPERATURES OCCURRED ON THE 21ST AND 22ND...WHEN HIGHS
WERE IN THE 90S. A RECORD HIGH OF 97 DEGREES WAS TIED AT
ABILENE ON THE 22ND.

VERY STRONG WINDS OCCURRED ACROSS A SMALL PART OF THE
CONCHO VALLEY...FROM BIG LAKE TO SAN ANGELO...DURING THE
EARLY MORNING HOURS OF THE 26TH. THIS MAY HAVE BEEN THE
RESULT OF SUBSIDING AIR FROM SHOWERS AND THUNDERSTORMS TO
THE SOUTH...AND POSSIBLY FROM A LOCALIZED HEATBURST EVENT.
A PEAK WIND GUST OF 63 MPH WAS RECORDED AT THE SAN ANGELO
REGIONAL AIRPORT. THESE HIGH WINDS CAUSED MULTIPLE POWER
OUTAGES IN THE SAN ANGELO AREA.

A SEVERE WEATHER AND HEAVY RAIN EVENT OCCURRED ON THE
26TH AND 27TH...AS UPPER LEVEL DISTURBANCES MOVED EAST
INTO THE REGION AND INTERACTED WITH A VERY MOIST AIRMASS.
SUPERCELL SEVERE STORMS TRACKED EAST ACROSS THE FAR
SOUTHERN PART OF WEST CENTRAL TEXAS...FROM CROCKETT TO
KIMBLE COUNTIES. THESE STORMS PRODUCED HAIL TO GOLFBALL
SIZE AT SEVERAL LOCATIONS...AND HAIL TO HEN EGG SIZE WAS
REPORTED NEAR SONORA. SOME HAIL AND WIND DAMAGE WAS
REPORTED IN AND AROUND SONORA. OTHER SCATTERED SEVERE
STORMS PRODUCED NICKEL SIZE HAIL AT STERLING CITY...SAN
ANGELO...AND BRADY.

THE STORMS WERE MOST NUMEROUS ACROSS CENTRAL AND
SOUTHERN PARTS OF WEST CENTRAL TEXAS...AND THE STORMS
CONTAINED VERY HEAVY RAINFALL. THE HEAVIEST RAIN AFFECTED
THE SOUTHEASTERN PART OF WEST CENTRAL TEXAS...WHERE
AMOUNTS OF 3 TO 5 INCHES WERE REPORTED. RAINFALL AMOUNTS
OF 1 TO 3 INCHES WERE COMMON ACROSS MUCH OF THE CONCHO
VALLEY AND NORTHERN EDWARDS PLATEAU...AND PARTS OF THE
HEARTLAND. WITH THE VERY HEAVY RAINFALL...FLASH FLOODING
OF ROADS OCCURRED AT NUMEROUS LOCATIONS ACROSS SUTTON
AND KIMBLE COUNTIES. A COUPLE OF ROADS WERE FLOODED IN
MCCULLOCH COUNTY...AND STREET FLOODING WAS REPORTED IN
SAN ANGELO.

WITH A MOIST AND UNSTABLE AIRMASS ALONG WITH THE PRESENCE
OF AN OUTFLOW BOUNDARY...THUNDERSTORMS OCCURRED ACROSS
THE NORTHERN BIG COUNTRY ON THE AFTERNOON OF THE 29TH.
THESE STORMS OCCURRED GENERALLY NORTH OF A LINE FROM ROBY
TO ALBANY. SEVERAL OF THE STORMS PRODUCED LARGE HAIL. THE
LARGEST HAIL SIZE REPORTS INCLUDED GOLFBALL SIZE 22 MILES
SOUTHWEST OF THROCKMORTON...AND HALF DOLLAR SIZE 5 MILES
WEST OF HAMLIN. RAINFALL AMOUNTS RANGED FROM ONE HALF TO
1.5 INCHES.

$$