Hail in Arizona, July 27, 2002

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
150 PM MST SAT JUL 27 2002

.SYNOPSIS...AS DRY WESTERLY FLOW ALOFT WILL REMAIN ACROSS NORTHERN
ARIZONA FOR THE NEXT FEW DAYS...LOOK FOR A DECREASE IN SHOWER AND
THUNDERSTORM ACTIVITY NORTH OF FLAGSTAFF. IT WILL REMAIN MOIST ENOUGH
FROM FLAGSTAFF SOUTH...FOR SHOWERS AND THUNDERSTORMS EACH DAY
LASTING THROUGH EARLY NEXT WEEK. BY THE SECOND HALF OF NEXT
WEEK...MORE MOISTURE ALONG WITH MORE SHOWERS AND THUNDERSTORMS WILL
RETURN TO MOST OF NORTHERN ARIZONA

.DISCUSSION...THUNDERSTORM ACTIVITY IS NOT QUITE AS MUCH AS EARLIER
THOUGHT...ESPECIALLY WITH THE INCREASES IN LOW LEVEL MOISTURE AS
SHOWN EARLIER IN THE DAY AND THE AVAILABLE CAPE OF 1400 J/KG FOR
THIS AFTERNOON AND ZERO INHIBITION. THERE IS MORE CONVECTIVE
DEVELOPMENT IN THE NORTHEAST...AS WEAK UPPER JET DYNAMICS AND
STRONGER FLOW ALOFT HELPING STORM TOP DIVERGENCE. GPS IPWV IS
SHOWING IPWV DECREASING TO AROUND 0.7 INCHES AT BELLEMONT THIS
AFTERNOON...EVIDENCE OF THE DRIER AIR MIXING TO THE SURFACE. AVN MAY
BE OVER DONE ON THE DRYING...AND WE CAN MAKE ADJUSTMENTS TO THE
FORECAST TO COMPENSATE FOR THIS BIAS. HOWEVER I DO THINK THE AVN
TREND FOR DRIER IS CORRECT AND SO WE WILL ADJUST PROBABILITY OF
PRECIP DOWNWARD THE NEXT COUPLE OF DAYS...ESPECIALLY LATE MONDAY
INTO TUESDAY WHEN THE UPPER HIGH SHIFTS OVER NORTHWEST PARTS OF THE
STATE WITH CONTINUED NORTHERLY FLOW.

EXTENDED...ECMWF AND MRF SHOWING THAT THE HIGH WILL SHIFT TO THE
EAST EITHER WEDNESDAY OR THURSDAY...DEPENDING UPON THE TIMING OF THE
TWO MODELS...ALLOWING FOR A MOIST SOUTHEAST FLOW TO BRING BACK THE
MONSOON. IT LOOKS AS IF AN EASTERLY WAVE GETS TRAPPED IN THE FLOW
JUST TO THE SOUTH OF ARIZONA...WHICH WILL TEND TO KEEP MOISTURE
CLOSE BY...ACROSS SOUTHERN SECTIONS OF THE STATE. SO FOR NOW WE WILL
GO WITH THE RETURN OF DEEPER MONSOONAL MOISTURE ON WEDNESDAY...AND
THEN LASTING THROUGH THE EXTENDED.
TC
.FGZ...NONE

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES LO/HI           PROBABILITY OF PRECIP
                 TON SUN   MON     TUE        TON SUN   MON     TUE
FLAGSTAFF        055/082 053/084 052/084      020 020 020 020 020 020
WINSLOW          064/095 064/095 065/095      020 020 020 010 010 000
PRESCOTT         063/090 061/091 060/092      000 020 010 010 010 020
PAGE             072/095 072/096 074/096      010 000 000 000 000 000
WINDOW ROCK      054/085 052/086 053/086      040 020 020 020 020 020
CANYON DE CHELLY 062/095 060/096 061/096      030 020 000 000 000 020
COTTONWOOD       073/101 071/102 070/103      000 010 020 010 010 020
GRAND CANYON     052/087 052/089 051/089      000 000 000 000 000 000
GREER            051/078 049/080 048/080      030 030 020 030 020 030
HEBER            056/087 054/089 053/089      020 030 020 030 020 030
JACOB LAKE       055/080 053/082 052/082      000 000 000 000 000 000
NAVAJO N.M.      060/091 058/092 059/092      020 020 000 000 000 020
PAYSON           064/093 062/094 061/096      020 010 020 020 020 030
SEDONA           069/099 067/100 066/101      000 020 010 010 010 020
SELIGMAN         056/093 054/094 053/095      000 010 010 010 010 010
SHOW LOW         058/086 056/088 055/088      030 020 020 020 020 020
ST. JOHNS        060/089 060/089 061/089      030 030 020 020 010 030
WUPATKI N.M.     067/097 067/097 068/097      020 020 020 010 000 010

AZZ004>018-037>040-251930-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1015 AM MST SAT JUL 27 2002

...SCATTERED SHOWERS AND THUNDERSTORM ACTIVITY OVER NORTHERN ARIZONA
TODAY EXCEPT FOR THE NORTHWEST WHERE IT WILL BE DRIER...

DISCUSSION...A DRY WESTERLY FLOW HAS MOVED OVER NORTHERN
ARIZONA...HOWEVER THERE HAS BEEN AN INCREASE IN MOISTURE OVERNIGHT
IN THE LOWER LEVELS FROM FLAGSTAFF SOUTH. THERE WILL BE MORE
INSTABILITY FOR THE THUNDERSTORMS TO WORK OFF OF TODAY...FROM
YAVAPAI COUNTY UP INTO PORTIONS OF THE LITTLE COLORADO RIVER VALLEY
WHERE THERE WILL BE AN ISOLATED THREAT OF SEVERE
THUNDERSTORMS...MAINLY LARGE HAIL AND STRONG GUSTY WINDS. AS A
RESULT OF THE INCREASES IN MOISTURE FROM FLAGSTAFF SOUTHEAST INTO
THE WHITE MOUNTAINS...A FEW OF THE STRONGER THUNDERSTORMS WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAIN.

BURNED AREA RAIN OUTLOOK...
SMALL AMOUNTS OF RAIN CAN CAUSE FLASH FLOODING IN BURNED OUT AREAS.

CHEDISKI-RODEO BURN AREA...SCATTERED SHOWERS AND THUNDERSTORMS ARE
EXPECTED THIS AFTERNOON AND EVENING. SOME STORMS MAY PRODUCE
RAINFALL AMOUNTS APPROACHING ONE INCH.

INDIAN BURN AREA...ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THIS AFTERNOON AND EARLY EVENING. SOME STORMS MAY PRODUCE RAINFALL
AMOUNTS APPROACHING THREE QUARTERS OF AN INCH.

AZZ004>018-037>040-251930-
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1015 AM MST SAT JUL 27 2002

...SCATTERED SHOWERS AND THUNDERSTORM ACTIVITY OVER NORTHERN ARIZONA
TODAY EXCEPT FOR THE NORTHWEST WHERE IT WILL BE DRIER...

DISCUSSION...A DRY WESTERLY FLOW HAS MOVED OVER NORTHERN
ARIZONA...HOWEVER THERE HAS BEEN AN INCREASE IN MOISTURE OVERNIGHT
IN THE LOWER LEVELS FROM FLAGSTAFF SOUTH. THERE WILL BE MORE
INSTABILITY FOR THE THUNDERSTORMS TO WORK OFF OF TODAY...FROM
YAVAPAI COUNTY UP INTO PORTIONS OF THE LITTLE COLORADO RIVER VALLEY
WHERE THERE WILL BE AN ISOLATED THREAT OF SEVERE
THUNDERSTORMS...MAINLY LARGE HAIL AND STRONG GUSTY WINDS. AS A
RESULT OF THE INCREASES IN MOISTURE FROM FLAGSTAFF SOUTHEAST INTO
THE WHITE MOUNTAINS...A FEW OF THE STRONGER THUNDERSTORMS WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAIN.

BURNED AREA RAIN OUTLOOK...
SMALL AMOUNTS OF RAIN CAN CAUSE FLASH FLOODING IN BURNED OUT AREAS.

CHEDISKI-RODEO BURN AREA...SCATTERED SHOWERS AND THUNDERSTORMS ARE
EXPECTED THIS AFTERNOON AND EVENING. SOME STORMS MAY PRODUCE
RAINFALL AMOUNTS APPROACHING ONE INCH.

INDIAN BURN AREA...ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THIS AFTERNOON AND EARLY EVENING. SOME STORMS MAY PRODUCE RAINFALL
AMOUNTS APPROACHING THREE QUARTERS OF AN INCH.