Severe Thunderstorm Warning 18, NWS Flagstaff, AZ

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
900 AM MST SUN AUG 03 1997

COPIOUS AMOUNTS OF MOISTURE CONTINUES TO WORK INTO THE CWA FROM THE
SOUTH. WATER VAPOR IMAGERY INDICATING UPPER LEVEL DISTURBANCE OVER
SOUTH CENTRAL AZ AT THIS TIME. A QUICK LOOK AT 12Z ETA-RUC APPEARS TO
HAVE PICKED UP ON THIS FEATURE IN ITS INITIALIZATION AT THE 5H
LEVEL...BUT IS PLACEMENT MAY BE A BIT TOO FAR TO THE NORTH. PREFER
NGM INITIALIZATION THIS MORNING. NGM TAKES THIS FEATURE SLOWLY TO THE
NORTHWEST INTO CENTRAL AZ...WITH THE ETA TRACKING IT INTO SOUTHERN CA
AND NV. APPEARS FROM WATER VAPOR IMAGERY THIS FEATURE WILL HEAD RIGHT
UP THE COLORADO RIVER VALLEY. WITH THE MOISTURE ALREADY IN PLACE...
THIS FEATURE PROVIDING ENOUGH DYNAMICS TO PRODUCE LARGE AREA OF
SHOWER ACTIVITY WITH EMBEDDED THUNDERSTORMS OVER YAVAPAI COUNTY.
LOOKING AT POSSIBILITY OF EXTENDING FLASH FLOOD WATCHES TO YAVAPAI
COUNTY...WITH RAINFALL RECEIVED FROM LAST NIGHT...IF ANY ADDITIONAL
HEAVY SHOWERS DEVELOP...IT COULD BE THAT FLASH FLOODING WILL BECOME
GOOD POSSIBILITY. NOTED SPC PLACED PORTIONS OF COUNTY UNDER SLIGHT
RISK TODAY AS WELL. FOR NOW...HAVE UPDATED ZONES INCREASING POPS AS
NEEDED.

FOR THE REST OF THE CWA...ANY SHOWER OR THUNDERSTORM THAT DEVELOPS
WILL NEEDED TO BE SFC HEATING INDUCED AS DYNAMIC KICKER NOT REALLY
PRESENT. NOTED SOME CLEARING TO BEGIN OVER NE AZ...IF THIS TREND
CONTINUES...THEN AFT SHOWER AND THUNDERSTORM ACTIVhITY SHOULD BEGIN ON
SCHEDULE TODAY...BEGINNING WITH THE HIGHEST ELEVATIONS FIRST. TEMPS
LOOKING GOOD ACROSS THE CWA...ALTHOUGH SOME LOCATIONS MAY NOT QUITE
GET AS WARM AS FORECAST WITH THE CLOUD COVER IN PLACE.
FLG 645  INW 524
FLG...NONE