Flash Flood Warning 16, NWS Cheyenne, WY

000
WGUS75 KCYS 012100
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
258 PM MDT WED AUG 1 2007

NEC007-105-WYC021-012145-
BANNER NE-KIMBALL NE-LARAMIE WY-
258 PM MDT WED AUG 1 2007

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 PM MDT FOR EAST
CENTRAL LARAMIE...NORTHWESTERN KIMBALL AND SOUTHWESTERN BANNER
COUNTIES...

AT 254 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE THUNDERSTORMS WITH VERY HEAVY RAIN DRIFTING TO THE SOUTH AT 
10 MPH.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ALBIN AND 
POINTS EAST...SOUTH...AND SOUTHWEST.

ADDITIONAL RAINFALL AMOUNTS OF ONE INCH ARE POSSIBLE BY 345 PM MDT.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN 
DEPTH BY FOOT OR BY AUTOMOBILE.

LAT...LON 4118 10414 4135 10373 4154 10393 4138 10432

$$

EISE

000
WGUS75 KCYS 012117
FFSCYS

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
314 PM MDT WED AUG 1 2007

NEC007-105-WYC021-012124-
BANNER NE-KIMBALL NE-LARAMIE WY-
314 PM MDT WED AUG 1 2007

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR EAST CENTRAL
LARAMIE...NORTHWESTERN KIMBALL AND SOUTHWESTERN BANNER COUNTIES...

THE HEAVIEST RAIN HAS SHIFTED SLIGHTLY SOUTH BUT STILL PERSISTS.
A NEW FLASH FLOOD WARNING WILL BE ISSUED FOR ROUGHLY THE SAME AREA 
BUT FOR A LONGER TIME.   

LAT...LON 4118 10414 4135 10373 4154 10393 4138 10432

$$

RE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHEYENNE WY
310 AM MDT WED AUG 1 2007

.SHORT TERM...TODAY THROUGH TONIGHT...

TODAY...AUGUST LOOKS TO MAKE A WET START. IMPRESSIVE LOW LEVEL
MOISTURE ADVECTING NORTHWESTWARD AS EVIDENCED BY CURRENT LOW TO
MID 60S DEWPOINTS ALONG AND EAST OF THE LARAMIE RANGE ALREADY. PER
TEMPERATURE/DEWPOINT SPREADS NEARING...EXPECT AREAS OF FOG TO
DEVELOP THROUGH MID MORNING EAST OF THE LARAMIE RANGE. 850 MB
DEWPOINTS AT 00Z/WEDNESDAY WERE IN THE 17C...63F RANGE ACROSS
WESTERN NEBRASKA. PRECIPITABLE WATER VALUES AT 00Z WERE 100-125
PERCENT OF NORMAL AND ARE PROGGED TO RANGE FROM 1 TO 1.5 INCHES BY
LATE AFTERNOON. SURFACE LOW PRESSURE WILL DEVELOP ACROSS NORTHERN
COLORADO WITH A WARM FRONT EXTENDING NORTHEASTWARD ACROSS
SOUTHEAST WYOMING EARLY THIS AFTERNOON. DEEPENING UPSLOPE UP TO
AND ABOVE 700 MB WILL DEVELOP THIS AFTERNOON EAST OF THE LARAMIE
RANGE. THIS LIFT ALONG WITH A SHORTWAVE TROUGH IN THE REGION WILL
HELP GENERATE SCATTERED TO NUMEROUS THUNDERSTORMS ALONG A LOW/MID
LEVEL THETA-E RIDGE AXII AND INSTABILITY AXIS NEAR THE COLORADO
STATE LINE. BECAUSE OF WEAK STEERING WINDS ALOFT...WILL SEE SOME
LOCALLY HEAVY RAINERS AND HAVE PUT THIS INTO GRIDDED FORECASTS.

TONIGHT...BELIEVE SCATTERED TO NUMEROUS THUNDERSTORMS WILL CONTINUE
WELL INTO THE NIGHTTIME HOURS AS DEEP UPSLOPE CONTINUES TO PROVIDE
FUEL FOR THUNDERSTORM REGENERATION AND WILL CONTINUE MENTION OF
LOCALLY HEAVY RAIN DUE TO WEAK STEERING WINDS AND HIGH PRECIPITABLE
WATER VALUES. WIDESPREAD FOG AND LOW CLOUDS LOOK LIKELY ACROSS THE
SOUTHERN 2/3RDS OF OUR FORECAST AREA PER BOUNDARY LAYER WIND
AND RELATIVE HUMIDITY PROGS.

.LONG TERM...THURSDAY THROUGH WEDNESDAY...
MID TO UPPER LEVEL MONSOONAL MOISTURE FETCH WILL BE FIRMLY
ENTRENCHED OVER THE CWA AT THE BEGINNING OF THE PERIOD. MOIST POST
FRONTAL SOUTHEASTERLY UPSLOPE FLOW WILL BE IN PLACE ACROSS AREAS
EAST OF THE LARAMIE RANGE ON THURSDAY. THE AIR MASS WILL BE SLIGHTLY
UNSTABLE ON THURSDAY...WITH LIS IN THE -1 TO -2 RANGE. PRECIPITABLE
WATER VALUES REMAIN IMPRESSIVE WITH 1.2 INCHES THE LOWEST PROGD
VALUE FROM NUMERICAL GUIDANCE. ADDITIONALLY A WEAK SHORTWAVE WILL
BE OVERHEAD...FURTHER AIDING CONVECTIVE DEVELOPMENT. SHOWERS AND
EMBEDDED WEAK THUNDERSTORMS WILL INCREASE IN COVERAGE THURSDAY
AFTERNOON AND EVENING. HEAVY RAIN WILL BE THE PRIMARY CONCERN WITH
VERY SLOW PROGD STORM MOTIONS. AFTERNOON TEMPERATURES WILL ALSO BE
SHARPLY COOLER ON THURSDAY...WITH SEQUENTIALLY DECREASING GUIDANCE
VALUES. THE COOLEST TEMPERATURES WILL BE IN FOOTHILL LOCATIONS
WHERE LOW STRATUS AND PRECIPITATION WILL EXIST. PWATS CHANGE VERY
LITTLE ON FRIDAY...SO AFTERNOON SHOWERS AND THUNDERSTORMS WILL
AGAIN BE POSSIBLE...WITH BEST COVERAGE IN AREAS WEST OF THE
LARAMIE RANGE. SOME DRYING WILL TAKE PLACE ON SATURDAY...HOWEVER
AREAS WEST OF THE LARAMIE RANGE WILL CONTINUE A SHOT AT SOME
AFTERNOON CONVECTIVE ACTIVITY.

BY SUNDAY THE BROAD UPPER HIGH WILL HAVE SHIFTED TO THE SOUTHERN
PLAINS...ALLOWING WESTERLIES TO DIP SOUTH INTO THE INTERMOUNTAIN
WEST...OPENING THE DOOR TO SHORTWAVES EMBEDDED WITHIN THE FLOW TO
INTRUDE THE AREA. THIS WILL TURN PRECIPITATION CHANCES TO MORE
ISOLATED IN NATURE...AND WILL ALSO ADD AT LEAST SOME STORM MOTIONS
WHICH SHOULD LIMIT THE HEAVY RAIN THREAT. NONETHELESS...RESULTANT
MOISTURE FIELDS WILL SUPPORT AFTERNOON AND EVENING THUNDERSTORM
POSSIBILITIES.

AFTER THE MUCH COOLER DAY ON THURSDAY...TEMPERATURES WILL REBOUND
BACK INTO THE UPPER 80S AND 90S QUICKLY FOR FRIDAY THROUGH THE
REMAINDER OF THE PERIOD.

&&

.AVIATION...AREAS OF MVFR AND IFR WILL DEVELOP THROUGH MID MORNING
ALONG AND EAST OF THE LARAMIE RANGE IN FOG AND LOW CLOUDS.
SCATTERED TO NUMEROUS THUNDERSTORMS WILL DEVELOP THIS AFTERNOON
AND CONTINUE WELL INTO THE NIGHTTIME HOURS TONIGHT PRODUCING MVFR.
WIDESPREAD IFR WILL DEVELOP LATE TONIGHT SOUTH OF A RAWLINS TO
CHADRON LINE IN LOW CLOUDS AND FOG.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.

&&

SHORT TERM/AVIATION...RUBIN
LONG TERM....HAHN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
1033 AM MDT WED AUG 1 2007

NEZ001>003-019>021-054-055-WYZ059>070-021115-
SIOUX-DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-
CHEYENNE-CONVERSE-NIOBRARA-SOUTHWEST CARBON-NORTH CARBON-
SNOWY RANGE-NORTH LARAMIE RANGE-LARAMIE VALLEY-LARAMIE RANGE-
PLATTE-GOSHEN-CHEYENNE FOOTHILLS-PINE BLUFFS-
1033 AM MDT WED AUG 1 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE WESTERN NEBRASKA
PANHANDLE AND SOUTHEAST WYOMING.

.DAY ONE...TODAY AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
AND TONIGHT OVER MOST AREAS. NO SEVERE STORMS ARE EXPECTED BUT A
FEW OF THE STRONGER STORMS MAY PRODUCE GUSTY WINDS AND SMALL HAIL.
LOCALIZED HEAVY RAINFALL IS ALSO POSSIBLE AS STORM MOVEMENT WILL
BE RATHER SLOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED
THURSDAY. STORMS SHOULD BE MORE ISOLATED IN NATURE FRIDAY INTO
EARLY NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED THROUGH TONIGHT...BUT SPOTTERS
ARE ENCOURAGED TO REPORT ANY HEAVY RAINFALL AMOUNTS.

&&

THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC...AND
CLIMATE INFORMATION IS AVAILABLE ON THE WEB AT...
HTTP://WEATHER.GOV/CHEYENNE