http://weather.yahoo.com/storm/USAZ0166.html
Severe Weather Alert
...EXTRAORDINARY SYSTEM TO IMPACT THE DESERT SOUTHWEST INTO THE
MEMORIAL DAY WEEKEND...
A DRASTIC CHANGE IN THE WEATHER PATTERN IS UNDERWAY ACROSS THE
SOUTHWEST UNITED STATES. THE HIGH PRESSURE SYSTEM WHICH BROUGHT
RECORD-BREAKING TEMPERATURES TO MANY LOCATIONS MONDAY AND TUESDAY HAS
WEAKENED AND MOVED EASTWARD. IN ITS WAKE...AN UNUSUALLY STRONG LOW
PRESSURE SYSTEM WILL TAKE OVER TODAY...AND REMAIN THE DOMINANT
WEATHER FEATURE HEADING INTO THE HOLIDAY WEEKEND.
AS THE LOW MOVES IN TODAY...STRONG WESTERLY WINDS WILL DEVELOP ACROSS
THE AREA. GUSTS OF 35 TO 45 MPH CAN BE EXPECTED DURING THE AFTERNOON
HOURS. THIS MAY RESULT IN AREAS OF BLOWING SAND AND DUST ACROSS THE
LOWER DESERTS. THE STRONG WINDS WILL BEGIN TO SUBSIDE DURING THE
EVENING HOURS..THOUGH BREEZY CONDITIONS WILL PERSIST THROUGH THE
NIGHT. HIGH TEMPERATURES TODAY WILL BE 10 TO 15 DEGREES COOLER THAN
YESTERDAY...AND MORE TYPICAL OF MID-MAY.
CLOUDS WILL INCREASE AND TEMPERATURES WILL CONTINUE TO COOL THURSDAY
AS THE LOW PRESSURE SYSTEM BEGINS TO WRAP-UP AS IT REMAINS CENTERED
NEAR LAS VEGAS. SCATTERED SHOWERS WILL ALSO BE POSSIBLE ACROSS THE
AREA THURSDAY...WITH THE GREATEST CHANCES ALONG THE FOOTHILLS NORTH
AND EAST OF PHOENIX. HOWEVER...THE BIGGEST...AND MOST IMPRESSIVE...
CHANGES WILL OCCUR THURSDAY NIGHT INTO SATURDAY.
CLOUDS WILL CONTINUE TO INCREASE...AND SHOWERS WITH EMBEDDED
THUNDERSTORMS WILL BECOME MORE WIDESPREAD AND NUMEROUS THURSDAY NIGHT
INTO FRIDAY AS THE STORM SYSTEM CONTINUES TO COOL AND SATURATE. SOME
OF THE THUNDERSTORMS MAY INCLUDE STRONG WINDS AND SMALL HAIL. THOUGH
IT MAY SOUND ODD...RECORD RAINFALL IS A POSSIBILITY FRIDAY.
HISTORICALLY...MAY AND JUNE ARE THE DRIEST MONTHS OF THE YEAR...AND
A STORM SYSTEM SUCH AS THE ONE MOVING IN IS A RARE EVENT. FOR
EXAMPLE...BASED ON DAILY WEATHER RECORDS FOR PHOENIX THAT DATE BACK
TO 1895...THERE HAS ONLY BEEN ONE YEAR WHEN MEASURABLE RAIN HAS
FALLEN ON MAY 23RD /0.10 INCHES IN 1992/.
WITH PLENTY OF CLOUDS AND SHOWERS AROUND FRIDAY...TEMPERATURES WILL
REMAIN IN THE LOWER 80S ACROSS SOUTHEAST CALIFORNIA AND SOUTHWEST
ARIZONA. ACROSS SOUTH-CENTRAL ARIZONA...INCLUDING PHOENIX...THE
GREATER COVERAGE OF CLOUDS AND SHOWERS WILL HOLD TEMPERATURES IN THE
LOWER TO MID 70S. THE LOWEST THE HIGH TEMPERATURE HAS EVER BEEN ON
MAY 23RD IS 70 DEGREES...WHICH WE WILL BE GETTING CLOSE TO. IT IS
ALSO OVER 30 DEGREES BELOW AVERAGE...AND NEARLY 40 DEGREES BELOW THE
HIGH OF 110 THIS PAST MONDAY.
THE SYSTEM WILL BEGIN TO WEAKEN ON SATURDAY...MEANING SHOWERS WILL
TAPER OFF AND CLOUDS WILL BEGIN TO THIN. TEMPERATURES WILL ALSO BEGIN
TO WARM UP. BY SUNDAY...HIGH TEMPERATURES WILL BE NEARING 90...WITH
NEAR AVERAGE TEMPERATURES LIKELY MEMORIAL DAY.
