Flash Flooding in Utah, July 28, 2003

UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
415 PM MDT MON JUL 28 2003

.SYNOPSIS...HIGH PRESSURE ALOFT WILL BE OVER NEVADA THROUGH
WEDNESDAY. THE RESULTING NORTHERLY FLOW WILL KEEP DRY AIR OVER THE
NORTH AND SLOWLY DRY THE AIRMASS OVER THE SOUTHERN PORTION OF UTAH.
THE HIGH SHIFTS EAST AFTER MIDWEEK ALLOWING MOISTURE TO INCREASE
AGAIN INTO THE WEEKEND.

.DISCUSSION...FOR THIS EVENING ISSUED A FLASH FLOOD WATCH OVER AND
NEAR THE SOUTHERN MOUNTAINS BASED ON PRECIPITABLE WATER AND RADAR
PRECIPITATION ESTIMATES.  SPOTTER REPORTS RECEIVED SINCE THE
ISSUANCE SUGGEST THE RADAR ESTIMATES ARE AT LEAST DOUBLE THE AMOUNT
REACHING THE GROUND.  SO IT APPEARS THE THREAT OF FLASH FLOODING IS
LOW BUT WILL LEAVE THE WATCH FOR AT LEAST ANOTHER COUPLE OF HOURS
THEN IT CAN BE REASSESSED.  CURRENT EXPIRATION IS SCHEDULED FOR 10
PM OR 04Z.

RIDGE WILL CONTINUE TO SHIFT INTO AND ACROSS NV OVER THE NEXT DAY OR
TWO.  THAT WILL SPREAD A NORTHERLY FLOW OVER MOST OF THE AREA AND
CONTINUE A DRYING TREND FROM THE NORTH. SOME MOISTURE WILL REMAIN
NEAR THE AZ BORDER BUT THERE SHOULD BE SOME DECREASE EVEN THERE.
TEMPERATURES WILL CLIMB A LITTLE AS THE RIDGE BECOMES DOMINANT AND
THE RESULTING DECREASE IN AFTERNOON CLOUDS WILL HELP THAT A BIT
ALSO.

AFTER MIDWEEK THE RIDGE STARTS SHIFTING EAST AGAIN WITH THE AXIS BY
THURSDAY MORNING FROM NORTHWEST UT TO SOUTH CENTRAL CO.  AREAS SOUTH
OF THE RIDGE AXIS WILL SEE MOISTURE BEGIN TO INCREASE AGAIN.  THAT
PROCESS EXPANDS OVER MOST OF THE AREA AS THE RIDGE CONTINUES EAST
AND SOUTHERLY FLOW SPREADS NORTH AND EAST.  THEN NOT A LOT OF CHANGE
FOR A COUPLE OF DAYS BUT WITH THE GFS INDICATING THERE COULD BE A
FEW WEAK SHORTWAVES RIPPLING NORTHWARD OVER THE AREA.

BY SUNDAY/MONDAY SOME DRYING SPREADS INTO THE AREA FROM THE
SOUTHWEST BUT BEING THAT FAR OUT WE WILL KEEP SOME ACTIVITY IN THE
PACKAGE FOR NOW.

SLC 0000  CDC 3222 SANDERS

.SLC...FLASH FLOOD WATCH SOUTH CENTRAL UT UNTIL 04Z.

IDZ024-025-UTZ001>021-WYZ021-291300-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
357 PM MDT MON JUL 28 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN TWO-THIRDS OF
UTAH...EXTREME SOUTHEAST IDAHO AND EXTREME SOUTHWEST WYOMING

.DAY ONE... TODAY

THUNDERSTORMS HAVE DEVELOPED ONCE AGAIN ACROSS THE SOUTHERN THIRD OF
UTAH THIS AFTERNOON MAINLY OVER THE HIGHER TERRAIN. SOME OF THESE
STORMS COULD PRODUCE HEAVY RAINFALL. LOCAL FLOODING OF DRY WASHES
AND SMALL STREAMS IS A POSSIBILITY THIS AFTERNOON THROUGH EARLY THIS
EVENING. SEE SLCFFASLC FOR DETAILS.

.DAYS TWO THROUGH SEVEN... TUESDAY THROUGH SUNDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

WCJIN-WYSW