Severe Thunderstorm Warning 5, NWS Flagstaff, AZ

NORTHERN ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
230 PM MST WED JUN 28 2000

SYNOPSIS...SHOWERS AND THUNDERSTORMS WILL GRADUALLY DISSIPATE DURING
THE OVERNIGHT HOURS ACROSS NORTHERN ARIZONA. MOISTURE WILL REMAIN
OVER THE AREA THROUGH THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS
OVER THE SOUTHWESTERN UNITED STATES. EXPECT SHOWERS AND
THUNDERSTORMS TO DEVELOP AGAIN EACH AFTERNOON FOR THE NEXT SEVERAL
DAYS OVER THE HIGHER TERRAIN OF NORTHERN ARIZONA...WITH LITTLE
CHANGE IN DAYTIME HIGH...AND NIGHT TIME LOW TEMPERATURE READINGS.

DISCUSSION...CONVECTION FIRED OFF MORE OR LESS ON SCHEDULE...WITH
OUTFLOW BOUNDARIES CURRENTLY DROPPING OFF OF THE MOGOLLON RIM INTO
NORTHERN YAVAPAI COUNTY...AND NORTHERN GILA COUNTY. CONVECTION ALSO
OCCURRING OVER THE HIGHER MOUNTAINS OF YAVAPAI COUNTY. THIS TREND
SHOULD CONTINUE THROUGH THE LATE AFTERNOON INTO THIS EVENING...WITH
OUTFLOW BOUNDARIES KICKING OFF MORE WIDESPREAD CONVECTION IN YAVAPAI
COUNTY THROUGH THE EVENING HOURS. IN ADDITION...CONV DEVELOPMENT
ALSO NOTED OVER FAR EASTERN MTNS.

12Z MODELS IN GENERAL AGREEMENT WITH OVERALL PATTERN THROUGH 48
HRS...WITH MINOR DIFFERENCES NOTED HOW MODELS HANDLE WEAK VORT LOBES
ROTATING AROUND MAIN HIGH PRESSURE CELL TO BECOME ENTRENCHED OVER
THE SW US. WITH THESE WAVES PRESENT...THERE SHOULD BE NO PROBLEM IN
KEEPING MOISTURE PUMPING NORTHWARD FROM OLE MX OVER THE NEXT COUPLE
OF DAYS FOR A CONTINUATION OF SCT AFTERNOON SHOWER AND THUNDERSTORM
ACTIVITY. FOR TEMPS...DESPITE INCREASE IN HEIGHT VALUES OVER THE
NEXT FEW DAYS...INCREASED MOISTURE AND CLOUDS WILL KEEP MAX TEMPS
SUPPRESSED BY A FEW DEGREES. MOS GUIDANCE APPEARS TO HAVE A BIT OF A
WARM BIAS. THUS...WILL MAKE A FEW MINOR ADJUSTMENTS TO MOS GUIDANCE.

IN THE EXTENDED...MRF KEEPS 5H HIGH OVER THE SW US THROUGH THE PD.
NRN AZ WILL BE UNDER FAVORABLE FLOW FOR A CONTINUATION OF MOISTURE
FEED FROM THE S. WILL KEEP MENTION OF THUNDERSTORMS IN FCST...AS
THERE IS NO SIGN OF MOISTURE BEING CUT-OFF BY WESTERLY FLOW FOR THE
TIME BEING.
MCGRATH

.FGZ...NONE.

AZZ004>018-037>040-282030-

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
926 AM MST WED JUN 28 2000

...HEAVY RAIN PRODUCING THUNDERSTORMS POSSIBLE TODAY...MAINLY SOUTH
OF FLAGSTAFF...

SPOTTER REPORTS OF HEAVY RAINFALL REQUESTED.

A LARGE THUNDERSTORM COMPLEX OVER NORTHERN MEXICO PUSHED ADDITIONAL
LOW LEVEL MOISTURE INTO NORTHERN ARIZONA LAST NIGHT. YAVAPAI AND
GILA COUNTY HAD THE BEST INCREASES IN MOISTURE. DAYTIME HEATING AND
INCREASING INSTABILITY WILL LEAD THE THE DEVELOPMENT OF AFTERNOON
SHOWERS AND THUNDERSTORMS. THE STORMS WILL DEVELOP OVER THE MOGOLLON
RIM...AND HIGHER TERRAIN IN YAVAPAI COUNTY...AS WELL AS THE HIGHER
TERRAIN OF THE REMAINING PORTION OF NORTHERN ARIZONA. MID LEVEL
WINDS SHOULD STEER THESE STORMS INTO THE VALLEY LOCATIONS OF YAVAPAI
COUNTY AND NORTHERN GILA COUNTY LATER THIS AFTERNOON. SOME OF THESE
STORMS WILL CONTAIN LOCALLY HEAVY DOWNPOURS AND SMALL HAIL.

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 WARNINGS ...AND
FOLLOW-UP STATEMENTS.
MCGRATH

AZZ004>018-037>040-282030-

HAZARDOUS WEATHER OUTLOOK...CORRECTION
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
935 AM MST WED JUN 28 2000

...HEAVY RAIN PRODUCING THUNDERSTORMS POSSIBLE TODAY...MAINLY SOUTH
OF FLAGSTAFF...

SPOTTER REPORTS OF HEAVY RAINFALL REQUESTED.

A LARGE THUNDERSTORM COMPLEX OVER NORTHERN MEXICO PUSHED ADDITIONAL
LOW LEVEL MOISTURE INTO NORTHERN ARIZONA LAST NIGHT. YAVAPAI AND
GILA COUNTY HAD THE BEST INCREASES IN MOISTURE. DAYTIME HEATING AND
INCREASING INSTABILITY WILL LEAD TO THE DEVELOPMENT OF AFTERNOON
SHOWERS AND THUNDERSTORMS. THE STORMS WILL DEVELOP OVER THE MOGOLLON
RIM...AND HIGHER TERRAIN IN YAVAPAI COUNTY...AS WELL AS THE HIGHER
TERRAIN OF THE REMAINING PORTION OF NORTHERN ARIZONA. MID LEVEL
WINDS SHOULD STEER THESE STORMS INTO THE VALLEY LOCATIONS OF YAVAPAI
COUNTY AND NORTHERN GILA COUNTY LATER THIS AFTERNOON. SOME OF THESE
STORMS WILL CONTAIN LOCALLY HEAVY DOWNPOURS AND SMALL HAIL.

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 WARNINGS ...AND
FOLLOW-UP STATEMENTS.
MCGRATH