Severe Thunderstorm Warning 54, NWS Flagstaff, AZ

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST WED AUG 30 2000

SYNOPSIS...A VERY MOIST AND UNSTABLE SOUTH FLOW WILL CONTINUE ACROSS
NORTHERN ARIZONA TONIGHT AND THURSDAY. THIS WILL RESULT IN
THUNDERSTORMS ACROSS THE EASTERN MOUNTAINS THROUGH TONIGHT. THERE IS
A POTENTIAL FOR STRONG THUNDERSTORMS AGAIN THURSDAY. DRIER AIR WILL
MOVE OVER NORTHERN ARIZONA BY FRIDAY AND WARMING WILL CONTINUE INTO
THE WEEKEND.

DISCUSSION...VORT MAX OVER SERN AZ IS MOVING NORTH AS EXPECTED.
STORMS IN CENTRAL YAVAPAI AND NERN GILA COUNTY HAVE TOPPED OFF AT
HALF INCH HAIL SO FAR. WILL CONTINUE THE CURRENT FCST WITH A FF
WATCH IN THE SERN CWA THROUGH 04Z AND THE SVR WATCH ACROSS MOST OF
THE SOUTHERN CWA THROUGH 00Z. STORMS WILL CONTINUE MOVING NORTH
ALONG THE NEW MEXICO BORDER...THROUGH THE WHITE MTNS EARLY AND
REACHING THE NERN ZONES UNTIL AFTER MIDNIGHT. WITH SOME CLEARING
LATER MAINLY IN THE SOUTHWEST...WE ARE LIKELY TO SEE STORMS
REDEVELOP ACROSS THE EASTERN ZONES AGAIN THURSDAY. UPPER LEVEL WINDS
ARE INCREASING AND MAY HELP ORGANIZE STORMS IN THE AREA...SO A
CHANCE OF SVR WX MAY DEVELOP MAINLY IN THE SERN ZONES. STORMS MAY
CONTINUE INTO THE EVENING ESPECIALLY ACROSS THE NORTHERN ZONES. BY
FRIDAY...DRYING WILL START MOVING INTO THE CWA...BUT CANNOT RULE OUT
THE CHANCE OF ISOLATED PRECIP. WILL CARRY 20 PCT POPS IN THE
SOUTHWEST WHERE MOST DRYING IS LIKELY...AND UP TO 40 PCT POPS IN THE
NERN ZONES WHERE MOISTURE WILL LINGER FOR THE LONGEST TIME.

IN THE EXTENDED...SATURDAY THROUGH MONDAY...CLEARING IS LIKELY TO
TAKE PLACE EXCEPT FOR SOME LINGERING CLOUD COVER ON SATURDAY.
FURTHER DRYING WILL RESULT IN MOSTLY SUNNY AND BREEZY CONDITIONS
THROUGH THE REST OF THE EXTENDED PD.

PEREZ

.FGZ...SVR TSTORM WATCH TIL 31/00Z FOR AZ ZONES 8/16/17/18/37
       FLASH FLOOD WATCH FROM TIL 31/04Z FOR AZ ZONES 16/17/18.

1

AZZ004>018-037>040-302030-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
930 AM MST WED AUG 30 2000

...SHOWERS AND THUNDERSTORMS WILL PRODUCE WIDESPREAD HEAVY RAIN
TODAY ACROSS NORTHERN ARIZONA...

...FLASH FLOOD WATCH FROM 1200 PM TO 9 PM MST FOR THE WHITE
MOUNTAINS...EASTERN RIM COUNTRY...NORTHERN GILA COUNTY AND YAVAPAI
COUNTY...

SPOTTER REPORTS OF HEAVY RAIN AND FLOODING REQUESTED.

THE AIRMASS OVER NORTHERN ARIZONA IS VERY MOIST AND AN APPROACHING
TROUGH WILL RESULT IN WIDESPREAD SHOWERS AND THUNDERSTORMS AGAIN
TODAY. STORMS WILL DEVELOP ALL OVER ARIZONA TODAY...BUT SOME OF THE
HEAVIEST RAIN WILL OCCUR ACROSS THE WHITE MOUNTAINS AND EASTERN RIM
COUNTRY...NORTHERN GILA COUNTY AND YAVAPAI COUNTY. SOAKING RAINS
FROM YESTERDAYS STORMS ACROSS YAVAPAI COUNTY WILL MAKE THIS AREA
MORE SUSCEPTIBLE TO FLOODING...ALTHOUGH THE GREATEST RAINFALL TOTALS
ARE LIKELY TO OCCUR FARTHER EAST. CLOUDS WILL BE DEVELOPING THROUGH
THE MORNING WITH MOST OF THE RAIN BEGINNING BY THE EARLY AFTERNOON.
AS THE TROUGH MOVES THROUGH EASTERN ARIZONA LATER TODAY...THIS WILL
HELP STORMS TO CONTINUE PAST SUNSET. SHOWERS AND THUNDERSTORMS WILL
KEEP GOING LATE INTO THE NIGHT FROM AROUND ST. JOHNS TO DILKON AND
TUBA CITY.

MOST LOCATIONS ACROSS THE WATCH AREA WILL RECEIVE FROM A FEW TENTHS
OF AN INCH OF RAIN TO TWO OR MORE INCHES. LOCATIONS THAT ARE KNOWN
TO FLOOD SHOULD BE MONITORED TODAY. AVOID THESE LOCATIONS WHEN HEAVY
RAIN MOVES THROUGH THE REGION THIS AFTERNOON AND EVENING.

THE HAZARDOUS WEATHER OUTLOOK GIVES PRELIMINARY INFORMATION FOR THE
POSSIBILITY OF WEATHER THAT COULD BECOME SEVERE...DAMAGING WINDS IN
EXCESS OF 57 MPH...HAIL 3/4 INCH IN DIAMETER OR LARGER...AND HEAVY
RAINFALL THAT COULD CAUSE FLOODING OR RUNNING WASHES. WHEN HAZARDOUS
WEATHER BEGINS...IMPORTANT LIFE SAVING INFORMATION WILL BE PROVIDED
IN SHORT TERM FORECASTS...SEVERE WEATHER AND FLOOD WARNING...AND
FOLLOW-UP STATEMENTS.

PEREZ