Hail in Arizona, October 3, 2001

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST WED OCT 03 2001

.SYNOPSIS...DRIER AND MORE STABLE AIR WILL BRING MOSTLY SUNNY SKIES
TO THE AREA THURSDAY...WITH THE ONLY CHANCE FOR SHOWERS OVER THE
EASTERN MOGOLLON RIM AND WHITE MOUNTAINS. A DEVELOPING LOW PRESSURE
SYSTEM WILL BRING A CHANCE OF SHOWERS BACK TO THE HIGHER ELEVATIONS
EAST OF FLAGSTAFF FRIDAY AND SATURDAY. THIS STORM SYSTEM WILL MOVE
THROUGH NORTHERN ARIZONA LATE IN THE WEEKEND...WITH WINDY CONDITIONS
EXPECTED...AND A CHANCE FOR SHOWERS ACROSS ALL OF THE AREA BY
SUNDAY. MUCH COLDER TEMPERATURES WILL ALSO ACCOMPANY THIS STORM
SUNDAY AND MONDAY. A SECOND STORM SYSTEM WILL KEEP THE CHANCE FOR
SHOWERS ACROSS NORTHERN ARIZONA WELL INTO NEXT WEEK...WITH BELOW
NORMAL TEMPERATURES CONTINUING.

.DISCUSSION...SHOWERS AND THUNDERSTORMS HAVE BEEN FIRING ALONG THE
RIM AND EASTERN MOUNTAINS EASILY THIS AFTERNOON. STORM MOTION HAS
BEEN FOLLOWING THE MEAN FLOW SOUTHWARD OFF THE RIM AND EVENTUALLY
INTO THE PHX CWA. COOL POCKET OF AIR AT THE MID-LEVELS WILL SINK A
BIT FURTHER SOUTH TONIGHT. WARMER AIR ALOFT WILL REPLACE THIS
AIRMASS THURSDAY...WITH MOST OF NORTHERN ARIZONA BECOMING CAPPED.
THE EXCEPTION WILL BE THE FARTHEST SOUTH AND EAST ZONES...WILL BE
CARRYING SLIGHT CHANCE POPS OVER THE WHITES AND EASTERN RIM AGAIN ON
THURSDAY.

BY FRIDAY...ANOTHER SHOT OF COLDER AIR AT THE MID-LEVELS WILL ENTER
THE NORTHERN SECTIONS OF THE STATE...DESTABILIZING THE AIRMASS YET
AGAIN. WOULD EXPECT CONVECTION TO DEVELOP OVER THE SAME AREAS AS WE
ARE SEEING TODAY AGAIN ON FRIDAY. LOCALLY BREEZY CONDITIONS WILL
ALSO DEVELOP AS A TROUGH BEGINS TO DROP INTO THE GREAT BASIN.

THIS TROUGH WILL NOT BE AS STRONG OR AS FAR SOUTH AS TUESDAYS AVN
RUNS INDICATED. HOWEVER...THIS IS NOT BECAUSE THE SPLIT IS NOT
DEVELOPING AS PROMISED...OR BECAUSE THERE WILL NOT BE AS MUCH ENERGY
IN THE SOUTHERN BRANCH. IT IS SIMPLY BECAUSE THE AVN/MRF MEMBERS ARE
FORECASTING AN EVEN STRONGER TRAILING SYSTEM WHICH WILL SAP THE LEAD
SYSTEM OF ITS STRENGTH. WILL EXPECT WINDY CONDITIONS TO DEVELOP OVER
THE WEEKEND WITH THE LEAD SYSTEM...AND EXPECT A GOOD DEAL OF THE
STILL PLENTIFUL MOISTURE TO THE SOUTH TO BE ADVECTED NORTHWARD
TOWARDS THE LOW PRESSURE. THE TRAILING SYSTEM WILL ALSO HAVE THIS
MOISTURE TO WORK WITH...AND POSSIBLY EVEN MORE DYNAMICS. WILL BRING
IN SCATTERED POPS EAST OF FLAGSTAFF SATURDAY...WITH CWA-WIDE POPS
BROADBRUSHED IN SUNDAY THROUGH WEDNESDAY WITH THE DUAL LOW PRESSURE
SYSTEMS. TEMPERATURES WILL ALSO TAKE QUITE THE NOSE-DIVE WITH LEAD
SYSTEM AND STAY DOWN WELL INTO NEXT WEEK. FROM TODAY...EXPECT NEARLY
15 TO 20 DEGREES OF COOLING BY SUNDAY OR MONDAY. WILL NOT BE
FORECASTING HIGH ELEVATION WET SNOW AS OF YET...BUT COLD POOL WILL
NEED CAREFUL WATCHING THIS WEEKEND. PETERSON.

.FGZ...NONE.