Flash Flood Warning 48, NWS Salt Lake City, UT

702 
WGUS75 KSLC 171708
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1108 AM MDT SAT AUG 17 2013

UTC017-025-171830-
/O.CON.KSLC.FF.W.0048.000000T0000Z-130817T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE UT-GARFIELD UT-
1108 AM MDT SAT AUG 17 2013

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1230 PM MDT FOR
SOUTH CENTRAL GARFIELD AND NORTHEASTERN KANE COUNTIES...

AT 1100 AM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED UP 
TO 1.5 INCHES OF RAIN HAD FALLEN ACROSS THE WARNED AREA. 
THUNDERSTORMS HAVE ENDED...HOWEVER EXCESSIVE RUNOFF FROM THIS 
RAINFALL IS LIKELY RESULTING IN FLASH FLOODING WITHIN SPOOKY 
GULCH...COYOTE   GULCH...EGYPT 3 SLOT CANYON...AND 25 MILE WASH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3759 11116 3740 11098 3736 11115 3759 11138

$$

MPS

022 
WGUS75 KSLC 171825
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1225 PM MDT SAT AUG 17 2013

UTC017-025-171834-
/O.EXP.KSLC.FF.W.0048.000000T0000Z-130817T1830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE UT-GARFIELD UT-
1225 PM MDT SAT AUG 17 2013

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1230 PM MDT FOR SOUTH
CENTRAL GARFIELD AND NORTHEASTERN KANE COUNTIES...

THUNDERSTORMS HAVE ENDED AND EXCESSIVE RUNOFF HAS LIKELY RECEDED. 
THEREFORE THE FLASH FLOOD WARNING FOR KANE AND GARFIELD COUNTIES HAS 
BEEN ALLOWED TO EXPIRE. 

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

LAT...LON 3759 11116 3740 11098 3736 11115 3759 11138

$$

MPS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
935 AM MDT SAT AUG 17 2013

.SYNOPSIS...WITH SOUTHERLY FLOW IN PLACE...A MOIST AIRMASS WILL
MOVE NORTHWARD INTO THE STATE TODAY. HIGH PRESSURE WILL FLATTEN
TOMORROW CAUSING SOME DRYING BEFORE MOISTURE RETURNS IN EARNEST
BEGINNING MONDAY. DRIER AIR WILL MOVE INTO WESTERN UTAH BEGINNING
WEDNESDAY.

&&

.DISCUSSION...HIGH PRESSURE REMAINS CENTERED EAST OF THE FORECAST
AREA THIS MORNING...ALLOWING A WEST TO SOUTHWEST FLOW TO DRAW
MOISTURE NORTHWARD. PLENTY OF ACTIVITY HAS ALREADY COMMENCED
ACROSS SOUTHERN UTAH FROM THE MOUNTAINS EASTWARD AND HAVE UPDATED
MORNING FORECAST TO ADDRESS THIS. GOES SATELLITE DERIVED PW IS IN
THE 1.0 TO 1.2 INCH RANGE ACROSS SOUTHEAST UTAH AND PORTIONS OF
THE CENTRAL MOUNTAINS...WITH VALUES IN THE 0.6 TO 0.8 INCH RANGE
ELSEWHERE. DRY LIGHTNING A POSSIBILITY WITH ANY CONVECTION THAT
DEVELOPS ACROSS NORTHWEST UTAH AS THE BOUNDARY LAYER REMAINS
RELATIVELY DRY.

ELSEWHERE ACROSS THE WARNING AREA...INCREASED MOISTURE...GOOD
INSTABILITY...AND LIGHT FLOW WILL ENHANCE THE POSSIBILITY OF
HEAVY RAIN WITH STORMS. STILL THINK THE THREAT OF FLASH FLOODING
IS SMALL AT THIS TIME...ALTHOUGH WILL HAVE TO KEEP AN EYE ON BURN
SCARS...AND SLOT CANYONS WEST OF LAKE POWELL.

&&

.AVIATION...SCATTERED CUMULUS CLOUDS BUILDING AROUND 8-9 KFT LATE
THIS MORNING MAY BRIEFLY TURN TO CEILINGS WITH A SMALL CHANCE OF
PRECIPITATION AFTER 20Z. THUNDERSTORMS FORMING ON THE SURROUNDING
HIGH TERRAIN MAY PRODUCE ERRATIC OUTFLOW WINDS AT THE TERMINAL
BETWEEN 21Z TO 03Z. PREVAILING SURFACE WINDS SHOULD REMAIN
BASICALLY SOUTHERLY THROUGH 18-20Z...THEN TURN TO LIGHT NORTHWEST
THROUGH 01-02Z.

&&

.FIRE WEATHER...EXTREME FIRE BEHAVIOR IS EXPECTED ACROSS NORTHWEST
UTAH AGAIN TODAY AS TEMPERATURES REMAIN ON THE HOT SIDE AND RH
VALUES HAVE YET TO RESPOND TO THE ADVANCING MOISTURE PLUME COMING UP
FROM THE SOUTH. SUFFICIENT MID-LEVEL MOISTURE HAS MOVED INTO
NORTHERN UTAH FOR HIGH-BASED CONVECTION THIS AFTERNOON AND EVENING.
RAINFALL WILL BE MINIMAL WITH THIS CONVECTION...SO WINDS AND
LIGHTNING WILL BE THE MAIN THREAT TODAY. HAVE ISSUED A RED FLAG
WARNING FOR ZONE 478 FOR THIS AFTERNOON THROUGH MID-EVENING. DOWN
SOUTH SCATTERED CONVECTION IS EXPECTED WITH A BETTER THREAT FOR
WETTING RAIN ACROSS THE HIGHER TERRAIN OF SOUTHERN AND CENTRAL UTAH
THIS AFTERNOON AND BEYONDS.

MOISTURE WILL CONTINUE TO DEEPEN ACROSS THE DISTRICT LATE IN THE
WEEKEND AND THROUGH AT LEAST THE FIRST HALF OF THE UPCOMING WEEK.
WETTING RAINS...HIGHER RH VALUES AND MODESTLY COOLER TEMPERATURES
WILL BECOME MORE COMMON THROUGH MIDWEEK OWING TO THE DEEP LAYER
MOISTURE ACROSS THE STATE. DRIER AIR WILL WORK INTO THE FAR WESTERN
DISTRICTS LATE IN THE WEEK...WITH SUFFICIENT MOISTURE ACROSS THE
SOUTHERN AND EASTERN DISTRICT TO MAINTAIN CONVECTION INTO THE END OF
THE WEEK.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR UTZ478.

WY...NONE.
&&

PUBLIC/AVIATION...YOUNG
FIRE WEATHER......SEAMAN

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
426 AM MDT SAT AUG 17 2013

UTZ001>016-019>021-517-518-WYZ021-181030-
CACHE VALLEY/UTAH PORTION-NORTHERN WASATCH FRONT-
SALT LAKE AND TOOELE VALLEYS-SOUTHERN WASATCH FRONT-
GREAT SALT LAKE DESERT AND MOUNTAINS-WASATCH MOUNTAIN VALLEYS-
WASATCH MOUNTAINS I-80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80-
WESTERN UINTA MOUNTAINS-WASATCH PLATEAU/BOOK CLIFFS-
WESTERN UINTA BASIN-CASTLE COUNTRY-SAN RAFAEL SWELL-
SANPETE/SEVIER VALLEYS-WEST CENTRAL UTAH-SOUTHWEST UTAH-
UTAHS DIXIE AND ZION NATIONAL PARK-SOUTH CENTRAL UTAH-
GLEN CANYON RECREATION AREA/LAKE POWELL-CENTRAL MOUNTAINS-
SOUTHERN MOUNTAINS-SOUTHWEST WYOMING-
426 AM MDT SAT AUG 17 2013

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

.DAY ONE...TODAY AND TONIGHT

MOISTURE OVER SOUTHERN UTAH WILL SPREAD NORTHWARD
TODAY...ALLOWING SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP
OVER MUCH OF THE FORECAST AREA THROUGH THIS EVENING. BRIEF HEAVY
RAIN IS POSSIBLE WITH THE STORMS OVER SOUTHERN UTAH...WHICH COULD
PRODUCE ISOLATED FLASH FLOODING. THE THREAT IS GREATEST IN SLOT
CANYONS AND NORMALLY DRY WASHES.

OVER NORTHERN UTAH...ANY STORMS THAT DEVELOP MAY HAVE GUSTY
OUTFLOW WINDS ASSOCIATED WITH THEM. ADDITIONALLY...DRY LIGHTNING
IS POSSIBLE WITH THESE STORMS AND THIS COULD LEAD TO NEW WILDFIRE
STARTS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE AIRMASS OVER THE OUTLOOK AREA WILL DRY OUT A BIT ON
SUNDAY...BUT MOISTURE IS EXPECTED TO INCREASE IN EARNEST MONDAY
AND TUESDAY. HEAVY RAIN WILL BECOME THE MAIN THREAT WITH SHOWERS
AND THUNDERSTORMS...PARTICULARLY OVER CENTRAL AND SOUTHERN
UTAH...DURING THIS TIME. DRIER AIR WILL MOVE INTO WESTERN UTAH
WEDNESDAY THROUGH FRIDAY. MOISTURE WILL REMAIN OVER EASTERN UTAH
DURING THIS TIME...KEEPING THE THREAT OF THUNDERSTORMS IN THE
FORECAST.

.SPOTTER INFORMATION STATEMENT...

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

FOR MORE INFORMATION FROM NOAA/S NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

FOR INFORMATION ON POTENTIAL TRAVEL IMPACTS VISIT...
HTTP://WWW.UDOTTRAFFIC.UTAH.GOV/ROADWEATHERFORECAST.ASPX