Damaging Wind in Arizona, July 31, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
111 PM MST THU JUL 31 2008

.SYNOPSIS...HIGH PRESSURE OVER ARIZONA WILL CONTINUE TO BRING DRIER
CONDITIONS AND HOTTER TEMPERATURES THIS WEEK. THE HIGH PRESSURE
CENTER WILL MOVE BACK NORTHEAST OF THE AREA BY FRIDAY AND
SATURDAY...WITH A RETURN TO A MORE SEASONAL CHANCE OF SHOWERS AND
THUNDERSTORMS BY THIS WEEKEND AND INTO EARLY NEXT WEEK.

&&

.DISCUSSION...VISIBLE SATELLITE IMAGERY SHOWS THAT SKIES ARE MOSTLY
CLEAR ACROSS ARIZONA WITH THE EXCEPTION OF A RATHER DECENT CU FIELD
OVER THE HIGHER TERRAIN OF EAST CENTRAL ARIZONA AND WEST CENTRAL NEW
MEXICO. THE CENTER OF CIRCULATION OF THE UPPER HIGH IS GENERALLY TO
THE NW OF THIS CU FIELD WITH THE MOVEMENT OF THE CLOUDS TO THE SW.
THE CLOSEST LIGHTNING STRIKES DURING THE PAST 15 MINUTES HAVE BEEN
OVER NORTH CENTRAL AND CENTRAL NEW MEXICO. I HAVE A SLIGHT CHANCE
FOR SHOWERS AND THUNDERSTORMS IN THE ZONES/GRIDS FOR THIS AFTERNOON
AND EVENING...BUT WILL HAVE TO MONITOR SATELLITE AND RADAR TRENDS
AND MAKE ADJUSTMENTS ACCORDINGLY.

THE MODELS CONTINUE TO PROG THE UPPER HIGH OVER ARIZONA TO MOVE NE
TO THE FOUR CORNERS REGION BY LATE THIS EVENING. THIS WILL BEGIN THE
PROCESS OF PULLING MOISTURE INTO THE STATE. STARTING TOMORROW WE
HAVE MAINLY SLIGHT CHANCE POPS FROM TUCSON EASTWARD TO THE NEW
MEXICO BORDER...WITH SLIGHTLY HIGHER RAIN CHANCES FOR THE MOUNTAIN
TOPS. ON SATURDAY THE GFS...NAM AND ECMWF SHOW THE RIDGE AXIS
GENERALLY EXTENDING FROM NRN NEW MEXICO TO THE CENTRAL PLAINS.
MEANWHILE...AN INVERTED TROUGH WILL BE MAKING ITS WAY WESTWARD UNDER
THE RIDGE BEGINNING ON SUNDAY...BUT THE AFFECTS WILL LIKELY HAVE THE
GREATEST IMPACT ON MONDAY. GFS SEEMS TO WANT TO MAINTAIN A FAIRLY
LOW GRADE RISK OVER THE WEEKEND AND INTO EARLY NEXT WEEK...AND IS
ONLY SHOWING ABOUT A 30 PERCENT RAIN CHANCE FOR MONDAY IN TUCSON.
ECMWF AND NAM PAINT A MUCH WETTER PICTURE. AS A RESULT...I INCREASED
THE POPS FOR SUNDAY AND MONDAY ACROSS THE BOARD...BUT ONLY NUDGED
THINGS UP ABOUT A CATEGORY THOUGH. AFTER MONDAY POPS SHOULD BE BACK
TO AROUND CLIMO.

HIGH TEMPS WILL BE AROUND 5 TO 7 DEGS ABOVE NORMAL FOR FRIDAY AND
SATURDAY WITH THE RIDGE NEARLY OVERHEAD. THEREAFTER...HIGHS WILL BE
SLIGHTLY BELOW NORMAL THROUGH THE REMAINDER OF THE FORECAST
PERIOD...BUT THE COOLEST DAYS WILL BE MONDAY AND TUESDAY. LOWS
WILL BE ABOVE NORMAL THROUGH THE ENTIRE FORECAST PERIOD...BUT THE
WARMEST MORNINGS WILL BE OVER THE WEEKEND.

&&

.AVIATION...MOSTLY CLEAR SKIES ACROSS SOUTHEAST ARIZONA...WITH THE
EXCEPTION OF SOME CU DEVELOPING OVER HIGHER TERRAIN. COULD SEE AN
ISOLATED SHOWER OR THUNDERSTORM DEVELOP OVER THE WHITE MOUNTAINS
THIS AFTERNOON AND EVENING. NORMAL DIURNAL WIND TRENDS EXPECTED THE
NEXT 24 HOURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

MOLLERE

WEATHER.GOV/TUCSON