Lightning Strike in Arizona, August 27, 2003

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
245 AM MST WED AUG 27 2003

.SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO BRING ABUNDANT TROPICAL
MOISTURE TO THE REGION TODAY...RESULTING IN A CONTINUATION OF HEAVY
SHOWERS AND THUNDERSTORMS. A DRYING TREND IS EXPECTED BY THE WEEKEND
OVER NORTHERN ARIZONA...WHILE A MOIST PATTERN WILL PERSIST OVER THE
REMAINDER OF THE STATE.

.DISCUSSION...COMPUTER PROBLEMS AT NCEP HAVE RESULTED IN MISSING
MODEL AND MOS DATA...SO ONLY A FEW CHANGES TO THE FORECAST AND GRIDS
FOR THIS PACKAGE.

CONVECTION HAS CONTINUED OVERNIGHT OVER LARGE PORTIONS OF NRN AZ.
EXPECT THIS ACTIVITY TO PERSIST THROUGH THE MORNING AND THEN
INCREASE QUICKLY IN COVERAGE AND INTENSITY THIS AFTERNOON. CONTINUED
HEAVY RAINFALL OVER NRN AZ THE PAST FEW DAYS AND THE LIKELIHOOD OF
HEAVY RAINFALL TODAY WILL REQUIRE THE ISSUANCE OF A FLASH FLOOD
WATCH FOR MUCH OF NRN AZ. MOISTURE CONTINUES TO STREAM NORTHWARD
FROM MEXICO AND THE GULF OF CALIF TODAY RESULTING IN PWAT VALUES IN
EXCESS OF ONE INCH AT FGZ THIS MORNING PER GPSMET DATA. THIS VALUE IS
IN THE 90TH PERCENTILE. EXPECT THE PATTERN ON THURSDAY TO BE SIMILAR
BUT WITH THE FLOW BEGINNING TO VEER MORE TO THE SOUTHWEST A BIT OF
DRYING WILL START TO TAKE PLACE...ESPECIALLY IN THE NRN ZONES. IN
ADDITION...INCREASING WESTERLIES OVER THE GREAT BASIN WILL RESULT IN
SUBSTANTIAL DEEP LAYER SHEAR. BY FRIDAY...AN APPROACHING S/W TROUGH
WILL PRODUCE AN INCREASE IN THE WESTERLY FLOW OVER THE NRN ZONES
ALONG WITH ADDITIONAL DRYING. ENOUGH MOISTURE IS EXPECTED TO REMAIN
OVER THIS REGION SO THAT THERE WILL BE A SLIGHT CHANCE OF SHOWERS.
PRESENCE OF STRONG SHEAR SUGGESTS THE POSSIBILITY OF SEVERE
THUNDERSTORMS THU/FRI OVER THE NRN ZONES. FARTHER SOUTH...SHEAR IS
GREATLY REDUCED BUT MOISTURE REMAINS HIGH SO THAT HEAVY PCPN IS MORE
LIKELY IN THESE AREAS.

.EXTENDED...WESTERLIES CONTINUE TO SCOUR OUT THE MOISTURE ACROSS NRN
AZ ON SATURDAY AND SUNDAY SO THAT CHANCES OF PCPN SHOULD DECREASE...
AND STORMS LESS LIKELY TO PRODUCE TORRENTIAL RAINFALL. LATE ON
SUNDAY...A WEST COAST TROUGH SETS UP AND WINDS BEGIN TO BACK MORE TO
THE SW AND S WHICH WILL BRING AN INCREASE IN MOISTURE ONCE AGAIN TO
THE AREA ON MONDAY.  DB

.FGZ...FFA YAVAPAI/COCONINO/GILA COUNTIES 10 AM UNTIL 11 PM.

.CODED TEMPERATURES/POPS FOR SELECTED CITIES IN NORTHERN ARIZONA

CITY             TEMPERATURES HI/LO           PROBABILITY OF PRECIP
                 TDY TON   THU     FRI        TDY TON   THU   FRI
FLAGSTAFF        074/052 075/051 077/050      060 060 040 040 030 030
WINSLOW          084/062 086/061 088/060      050 050 030 030 020 020
PRESCOTT         079/062 080/061 082/060      060 060 040 040 030 030
PAGE             090/073 088/072 090/071      030 030 020 020 020 020
WINDOW ROCK      080/053 078/053 080/051      040 040 030 030 030 030
CANYON DE CHELLY 086/061 084/061 086/059      030 040 020 020 020 020
COTTONWOOD       090/070 091/069 093/068      060 060 040 040 030 030
GRAND CANYON     075/052 076/051 078/050      050 050 030 030 030 030
GREER            069/049 070/048 072/047      060 060 050 050 040 040
HEBER            079/054 080/053 082/052      060 060 050 050 040 040
JACOB LAKE       072/052 073/051 075/050      040 040 030 030 020 020
NAVAJO N.M.      080/058 078/058 080/056      040 040 030 030 020 020
PAYSON           083/063 084/062 086/061      060 060 030 030 030 030
SEDONA           087/068 088/067 090/066      060 060 040 040 030 030
SELIGMAN         082/061 083/060 085/059      050 060 030 030 020 020
SHOW LOW         079/060 080/059 082/058      050 050 040 040 040 040
ST. JOHNS        079/057 081/056 083/055      040 040 030 030 020 020
WUPATKI N.M.     086/063 088/062 090/061      050 050 030 030 020 020

AZZ004>018-037>040-270200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1020 AM MST WED AUG 27 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN
GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA.

.DAY ONE...TODAY

...FLASH FLOOD WATCH FOR NORTHERN GILA...YAVAPAI...AND COCONINO
   COUNTIES TODAY UNTIL 11 PM MST...
...FLASH FLOOD WATCH EXTENDED TO INCLUDE NAVAJO AND APACHE COUNTIES
   UNTIL 11 PM MST...

A VERY MOIST AND UNSTABLE AIRMASS REMAINS ACROSS THE REGION TODAY.
LIGHT WINDS WILL FAVOR THUNDERSTORM DEVELOPMENT ACROSS THE HIGH
TERRAIN OF CENTRAL AND NORTHEAST ARIZONA BY LATE THIS MORNING.
STORMS WILL DRIFT SLOWLY OFF THE HIGHER TERRAIN AND INTO THE
SURROUNDING VALLEY AREAS. NORTHEAST AND NORTHERN SECTIONS OF THE
STATE WILL SEE SCATTERED THUNDERSTORM COVERAGE TODAY...HOWEVER THE
STORMS WILL BE STRONGER OVER NORTHERN SECTIONS DUE TO AN UPPER LEVEL
DISTURBANCE CROSSING THE AREA BY THIS AFTERNOON.

DUE TO THE VERY MOIST ATMOSPHERIC CONDITIONS...ISOLATED STRONGER
STORMS WILL PRODUCE TORRENTIAL RAIN THIS AFTERNOON. SATURATED SOIL
CONDITIONS MAY LEAD TO SOME FLOODING WITH THE STRONGEST STORMS
TODAY. THESE STORMS MAY ALSO PRODUCE HAIL AND GUSTY WINDS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH LABOR DAY

MOISTURE WILL REMAIN IN ABUNDANCE ACROSS THE STATE THROUGH THURSDAY.
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY WILL CONTINUE INTO
THURSDAY...BEFORE SLOWLY DECREASING BY THE WEEKEND.

FREQUENT HEAVY RAIN MAY WILL MEAN THAT THE FLOODING POTENTIAL WILL
REMAIN AT LEAST MODERATE THROUGH THE END OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

DEFINITION OF HAZARDOUS WEATHER...A WEATHER EVENT POSING A THREAT
TO LIFE AND PROPERTY.